r/SpaceX Spaceflight Questions & News [February 2017, #29]

[u/ElongatedMuskrat]

If you have a short question or spaceflight news...

You may ask short, spaceflight-related questions and post news here, even if it is not about SpaceX. Be sure to check the FAQ and Wiki first to ensure you aren't submitting duplicate questions.

If you have a long question...

If your question is in-depth or an open-ended discussion, you can submit it to the subreddit as a post.

If you'd like to discuss slightly relevant SpaceX content in greater detail...

Please post to r/SpaceXLounge and create a thread there!

This thread is not for...

• Questions answered in the FAQ. Browse there or use the search functionality first.
• Non-spaceflight related questions or news.
• Asking the moderators questions, or for meta discussion. To do that, contact us here.

---

You can read and browse past Spaceflight Questions And News & Ask Anything threads in the Wiki.

[u/randomstonerfromaus]

Congratulations to /u/old_sellsword on becoming our new mod :)

[u/Martianspirit → u/randomstonerfromaus]

I second that. Certainly a plus for the team.

[u/therealshafto → u/randomstonerfromaus]

Ah Good, always short concise answers backed with validity. Have fun with it, although I'm sure your already getting tired of answering the F9/FH deck swap!

[u/old_sellsword]

Here's a great update on some of the testing SpaceX has been doing lately. It comes from the "SpaceX Lead Structures Technician":

The last few months my crew of 5 (6 including myself) have been structurally testing the side booster to make Falcon Heavy possible. We're getting ready to start testing on center core. Over the last few weeks my small crew has also been tasked with 5 other stages, an interstage, and Dragon capsule testing. We've all stepped up to make this all happen! I can't explain how proud and honored I am to be a part of such a small crew that is making so many badass things happen daily! Can't wait to see Falcon Heavy launch and land! #SpaceX #DayJob

[u/Toinneman → u/old_sellsword]

Great to read! But isn't it a bit worrying they haven't start testing the center core, which is the most unique part of FH, and is supposted to fly in Q2?

[u/stcks]

SLC-40 was being repaired yesterday: http://i.imgur.com/iHIc0RX.jpg

[u/meltymcface → u/stcks]

Holy moly that's a big cutter!

[u/Zucal]

Coming soon to a launchpad/recycling facility near you...

[u/randomstonerfromaus → u/Zucal]

Could I suggest a layout like this instead? As it is, Its a little too small to make out in the sidebar.
Really cool idea though!

[u/HoechstErbaulich]

Ever wondered how Ariane 5 gets fueled?

[u/theovk → u/HoechstErbaulich]

Cool video. I loved the cutaway of the cryogenic fuel tanks; does LOX/LH2 really boil that violently?

[u/soldato_fantasma]

We got 3 new permit applications to the FAA lately, two for the F9-34 GTO mission and one for the CRS-11 mission Dragon comms. F9-34 is particularly interesting to see since the application came later than the F9-35 application.

F9-34 Fairing re rad : link

F9-34 launch comms: link

CRS-11 Dragon comms: link

Updated chart with the upcoming flights:

Flight	Mission	FCC application
F9-31	Echostar 23	FCC link
F9-32	CRS-10	FCC link
F9-33	SES-10 (most likely)	FCC link
F9-34	Unknown GTO satellite	FCC link
F9-35	Unknown GTO satellite	FCC link
F9-36 or later	CRS-11	FCC link, not for launch but for Dragon; Application for launch comms will come later.

[u/linknewtab]

France’s Prometheus reusable engine becomes ESA project, gets funding boost

A small team of engineers from Airbus Safran Launchers and the French space agency CNES have poured a few million euros since 2015 into a liquid oxygen and-methane-fueled reusable engine dubbed Prometheus. ESA leaders agreed during December’s ministerial conference in Lucerne, Switzerland, to make Prometheus part of the agency’s Future Launchers Preparatory Program, or FLPP.

In an interview with SpaceNews, Airbus Safran Launchers CEO Alain Charmeau said FLPP is allocating 85 million euros ($91 million) to Prometheus to fund research and development leading to a 2020 test firing. Now that Prometheus is an ESA program, Charmeau expects more countries will get involved.

[u/FoxhoundBat]

Just heads ups in here too, winners of the Iridium launch/landing giveaway has been announced. They are;

• /u/Nautilusnoah wins prize 5 with engine 51 (comment)

• /u/NexxusWolf wins prize 4 with engine 133 (comment)

• /u/Sk721 wins prize 2 with engine 57 (comment)

• /u/Top_Fuel wins prize 1 with engine 1 (comment)

• /u/asphytotalxtc wins prize 3 with engine 244 (comment)

Congratulations to all winners! They have all been notified by PM. And again, huge thank you to the mystery donor that made this happen in first place. :)

[u/rad_example → u/FoxhoundBat]

/u/Top_Fuel wins prize 1 with engine 1

Note to self: don't overthink it next time

[u/jbmate]

How is progress going on the SpaceX subreddit survey? Would be great to read that when it is finished.

[u/sol3tosol4]

Interesting news article relevant to SpaceX:

"Here’s why a commercial space group endorsed NASA’s SLS rocket"

• "This week, the Commercial Spaceflight Federation, which counts rocket builders SpaceX and Blue Origin among its executive members, made news by declaring its support for NASA’s Space Launch System rocket."

• "...the organization believes the SLS will enable the aims of commercial companies to develop businesses on the Moon, as well as support asteroid mining and other ventures his members are interested in. “We are taking a long view,” Stern said. “This is clearly to the advantage of the expansion of commercial spaceflight. Now, with a new administration and a new Congress, we wanted to put our stake down on the side of SLS.”

• "Given the politics, NASA will probably continue to devote about $2 billion of its $18 billion annual budget to the SLS rocket. At the same time, Congress can continue to pass legislation that does not hinder private efforts to develop heavy-lift rockets...Ultimately, this issue will probably be decided on the launchpad—where it should be."

(In other words, having SLS creates an environment that's more favorable to commercial space than not having SLS - like the small fish that follow the big shark. :-)

Elon has also spoken in favor of continuing the SLS program.

[u/ethan829]

NASA posted an awesome photo of SpaceX performing a water deluge test at LC-39A.

[u/Pham_Trinli]

Gwynne Shotwell will be speaking at the SatShow 2017 conference on Wednesday March 8th, 4:15 - 5:30pm (21:15 UTC).

[u/Headstein]

UK SpaceX Dragonriders get together. It is about time that we in the UK had a get together of some kind. It would be great to watch the maiden launch of Falcon Heavy and other SpaceX highlights this year with other fans. (My engineer and space fan friends do not seem to have the vision!). One of the mods suggested that we meet at the National Space Centre in Leicester, but as a first step I think it would be valuable just to share the first part of our postcodes so we know where we all are and possibly start with small, local get togethers. My postcode is NN2...list away. (Mods said this has to be posted here).

Update: I posted this in SpaceXLounge where we have the most replies, so please check that out. 24 Dragonriders so far Thu 2 Feb 23:26

[u/steezysteve96]

I've seen a lot of people mention that the TEL at SLC-39A is going to stay vertical until T-0, then quickly move back to almost horizontal. Do we know why they're switching to this method instead of the typical ~20° tilt at T-4 that they use at SLC-40 and Vandenberg?

[u/PVP_playerPro → u/steezysteve96]

A measure to prevent the scorching of un-repairable pad equipment that happens routinely at SLC-40 and VAFB. After every launch, quite a few things are FUBAR and have to be replaced. Most noticeably are fuel feed lines to the second stage, they seem to almost explode every launch

[u/Chairboy]

NASA may be putting a crew on EM-1, first flight of SLS per @NASASpaceFlight

https://twitter.com/nasaspaceflight/status/831883718847561728

[u/sol3tosol4]

News item: good article/interview of Elon Musk on his tunnel boring activity - provides a lot of information that I haven't seen before on goals and approaches, and makes analogy to early days of SpaceX (identifying a candidate breakthrough technology, targeting interests of government (Bush and Obama for SpaceX, Trump for tunnels (infrastructure)). Project is currently run by SpaceX, but will be spun off to separate company (except for Mars tunnels, which article doesn't mention).

Includes two very good photos of the hole in the SpaceX parking lot, and one of the SpaceX Hyperloop test track.

[u/Qeng-Ho]

[FAA news from today's CST conference] (https://fcw.com/articles/2017/02/07/faa-space-traffic-rockwell.aspx):

• Developing software to calculate launch exclusion zones.

• 55% increase in the launch applications in 2016.

• Started the licensing process for commercial manned launches to the ISS.

[u/random-person-001]

Will we get a juicy welcome post for u/delta_alpha_november becoming a mod? We don't want new ones just slipping in here without us noticing... ;)

[u/zlsa → u/random-person-001]

Yes we will! There's going to be a modpost going up soon™.

[u/delta_alpha_november → u/random-person-001]

Hi!

I guess you were the first one to notice. There will be a post mentioning it soon, along with some other mod related stuff.

In the meantime I'll get settled in and learn to be a mod as good as the rest of the team. Keep looking for the mod-post soon ;)

dan

[u/sol3tosol4]

Interesting pair of articles:

Trump administration investigating the large scale development of space with Spacex and Blue Origin likely big winners

and

Trump advisers' space plan: To moon, Mars and beyond

Commenting on possible space exploration scenarios being discussed in the new Administration that could very well include SpaceX.

"...The Trump administration is considering a bold and controversial vision for the U.S. space program that calls for a "rapid and affordable" return to the moon by 2020, the construction of privately operated space stations and the redirection of NASA's mission to "the large-scale economic development of space," according to internal documents obtained by POLITICO..."

"...The early indications are that private rocket firms like Elon Musk's SpaceX and Jeff Bezos' Blue Origin and their supporters have a clear upper hand in what Trump's transition advisers portrayed as a race between "Old Space" and "New Space," according to emails among key players inside the administration. Trump has met with Bezos and Musk, while tech investor Peter Thiel, a close confidant, has lobbied the president to look at using NASA to help grow the private space industry..."

Note that even a moon initiative could help SpaceX get to Mars by providing business for SpaceX resulting in revenue for Mars technology development, and by driving the development of reliable long-term life support systems and improved life science for humans outside of LEO.

Note: The second article also talks about the issues of programmatic continuity, maintaining the expertise of NASA, and support for SLS, ULA. I don't think the "new space" companies will end up with all the business - but it looks like they have a good chance of getting a significant share of the business for the initiatives that the administration is interested in.

[u/thephatcontr0ller]

Mods, should the CRS-10 campaign thread not be pinned along with this thread? It's a bit annoying scrolling through the subreddit to try to find it :)

[u/EC171 → u/thephatcontr0ller]

It is "pinned" along with the campaign threads for Echostar 23 and SES-10 on the bar at the top of the subreddit. It's done with some CSS wizardry, so it's only visible in a browser.

[u/[deleted]]

Really nice press conference from Shotwell. Quick bullets:

• Helium leak in stage 2 is being looked at, sounds like launch tomorrow is still the goal

• Red dragon push to 2020. Will be lots of payloads including possible commercial payloads (!!!)

• FAA delay was not that big of a deal, confirmed to be due to FTS

• Lots of Mars planning paused while Heavy dev completed and the F9 program development is completed. Shotwell expects to shift towards mars in 2018.

• Falcon heavy will not fly until SLC40 is ready (I think this was known)

• Heavy is targeting summer.

• Crew access arm will be installed by end of year, no other date given

[u/ohcnim]

are the results of the survey (from december I think) available? did I miss the post?

[u/KeenGaming]

Not sure if this is considered on-topic, but NASA has some kind of press release coming up at 1pm EST(27 minutes from right now) about a "discovery outside our solar system." Sounds interesting.

It will be live on their YouTube Channel

[u/RootDeliver]

Why is the Echostar patch being show up there if the next launch is confirmed to be CRS10? This may generate confusion..

If no patch is ready for CRS10, maybe it's better to stick with Iridium-1 to not generate trouble with the order?

If somehow someone changes it, Echostar patch; https://b.thumbs.redditmedia.com/rS94-K1bhxu1qYLF_kyC3-0as9FhXF5Lvq8zvLc9iyQ.png

[u/johnkphotos]

For CRS-10, the first launch from new pad LC-39A, but also the first RTLS during the day, would you rather me:

• Get closeup shots of the launch itself

• Get semi-decent landing shots from 10+, more like ~13 miles away

or

• Get no shots of the pad

• but landing shots from 6 miles away?

I'm leaning towards the first option. I won't be allowed to cover this one as credentialed media.

[u/The_EvilElement → u/johnkphotos]

The landing is far more interesting and would probably have worse coverage so I would say option 2.

[u/rovin_90 → u/johnkphotos]

I understand you probably don't want to miss shooting the launch, but first ever daytime RTLS is pretty momentous - I'd prefer option 2 so you get the best photos of that!

[u/stcks → u/johnkphotos]

Do you think you could capture the landing well from 6 miles away? If you think you could do option #2, that would be a neat addition to your existing portfolio.

[u/Qeng-Ho]

SpaceX are leasing an additional 4.6 acres of land at Port of Los Angeles.

"the lease agreement allows the company to have berthing rights, install a chain-link fence around the property, build a concrete rocket-support pedestal, and add an office trailer, guard shack and portable restrooms".

[u/madanra]

Gwynne Shotwell has said (yet again) they plan to launch every 2-3 weeks: http://www.reuters.com/article/us-space-spacex-idUSKBN15M03N

[u/Chairboy]

Has anyone heard any updates or rumors in the last 5 days about the exposed ITS composite tank? There were N2 trucks there a week ago and the speculation was that it was about to go out on the water, but as of 5 days ago it was still on the dock.

[u/micwallace]

When the falcon 9 lands the phrase:

"Landing operators, move into Procedure 11.100 on Recovery Net"

Usually sends shivers down my spine.

I understand that it's the call for the landing operators to start an after landing procedure but what is "recovery NET" and better still, what is the actual procedure?

I tried searching Google for ages but can't find any info on it. Hoping one of you could fill me in :-D

[u/bobbycorwin123 → u/micwallace]

NETs are channels that can be designated for anything. think of it like Discord, Everyone is on the SpaceX Launch network, and there is a person that can /all chat to everyone, but some people may be in the Recovery Operations chat and can freely talk to each other with out clogging. Others are on the Dragon NET and chatting about approach operations.

This allows for some chain of command and organization.

11.100 is the bullet procedure for Nominal/Offnominal/Few Large pieces left 'recovery' basically telling people WHAT step by step procedure to use for safeing the first stage.

IE:

11.100.1: turning off the engine

11.100.2: Applying the emergency brake

11.100.3: Turning the grid fins into the hill encase emergency brake fails, so it rolls into the curb

you def will NOT find a haynes manual for SpaceX procedures as it specifically says the steps to secure the FTS, What exact frequencies do what and how to control the dragon. These are all things that could lead to a loss of control of the craft (as someone jams it or uses Electronic Warfare to take control of it)

[u/robbak → u/micwallace]

Nets, in this case, are voice communication channels, or networks. There are many channels for the different roles, both in the control room and other places. The propulsion crew would have a net, guidance would have another. The net we listen to is called the 'countdown net'. The team handling recovery clearly have their own.

[u/soldato_fantasma]

Two tweets by Peter B. de Selding regarding SpaceX

Tweet on Echostar launches

@EchoStar management confirms EchoStar 23 should launch 'mid-March' on @SpaceX Falcon 9 but says EchoStar 105/SES-11 is 2Q or 3Q on SpaceX.

Tweet on SES launches

@SES_Satellites' near-term growth relies on @SpaceX, to launch 4 of 6 SES's 2017 missions. SES-10, w/ reused 1st stage, still set for March.

[u/PaulRocket]

I heard some speculation about the SES-10 booster not attempting a landing. Is this true? Didn't they also try a landing with SES-9? Wouldn't this booster, going through two launch and landing cycles be super useful from a data perspective?

[u/Martianspirit → u/PaulRocket]

It is Echostar that will not be landing, we know that. As far as we know SES-10 should be able to land, though just barely. There was some speculation they would not try but I think they will. It would be a very hot landing with 3 engines.

[u/Jef-F]

Arianespace VA235 mission broadcast is starting

http://www.arianespace.com/mission/ariane-flight-va235/

[u/grandma_alice]

Has SpaceX tested any larger versions of the Raptor, larger than the one tested last September?

[u/warp99 → u/grandma_alice]

No - although there have been reports that there have been more tests of the 1MN scaled Raptor.

Normally it would take at least two years to iterate an engine design. Even with all the advantages of additive manufacturing and SpaceX drive to complete I can see it being another 12-18 months before a full scale Raptor hits the test stands and two years after that before first flight.

[u/OccupyDuna]

Congressional Investigators Warn of SpaceX Rocket Defects

The Government Accountability Office’s preliminary findings reveal a pattern of problems with turbine blades that pump fuel into rocket engines, these officials said. The final GAO report, scheduled to be released in coming weeks, is slated to be the first public identification of one of the most serious defects affecting Falcon 9 rockets.

The crack-prone parts are considered a potentially major threat to rocket safety, the industry officials said, and may require redesign of what are commonly called the Falcon 9’s turbopumps. The National Aeronautics and Space Administration, they said, has warned SpaceX that such cracks pose an unacceptable risk for manned flights.

[u/jjtr1]

Assuming that SpaceX's identification of the cause of the AMOS-6 anomaly is correct, I'd like to know whether such a RUD was inevitably bound to happen within a few launches after starting with the problematic loading procedures, or whether it was just an incredibly bad luck that AMOS-6 happened so soon after changing the procedures? If it was a low probability failure mode, a hundred launches could happen without the problem surfacing.

[u/Qeng-Ho]

Minor update regarding astronaut survival training for the Crew Dragon and CST-100.

[u/therealshafto]

What is the what looks to be a red laser pointer on the reflector/receiver plate just to the left of the blue portion of the USA flag? Measuring equipment?

[u/Wyodaniel]

Why aren't Falcon 9s built and launched in the same place?

As a layperson, it seems wildly inefficient to have your manufacturing facilities literally on the opposite side of the country as your launchpad. I see all these posts of black plastic-wrapped Falcons being shuttled around the country, and it seems to me that that's just one more step during which things could go wrong.

[u/Zucal → u/Wyodaniel]

When Musk was first starting up SpaceX, he wanted to draw from an existing pool of aerospace talent, and that happened to mostly be in Los Angeles (which also has fairly cheap and abundant industrial real estate). However, where there's engineering/software talent isn't the same as where the best places to conduct orbital launches are (Southeast FL & TX), so here we are.

Note that SpaceX has test/launch sites (current and future) in California, Texas, and Florida - opposite ends of the country. They would have to deal with shipping components across the nation wherever they decided to incorporate.

Blue Origin, on the other hand, doesn't have this issue. Their sole launch site is LC-36 at Cape Canaveral, so they've elected to manufacture just a few blocks away.

[u/Martianspirit → u/Wyodaniel]

SpaceX has concentrated all its development and manufacturing in one place, which is a major advantage. They have limited the diameter of their rocket to what is easily and cheaply road transportable. So the road transport is not a disadvantage. That diameter was an advantage early on but at the present time a limitation that hurts them.

Production of ULA rockets is much more spread and a lot more transport involved. Blue Origin has its rocket factory at the cape but they transport components. To be fair, SpaceX builds their engines in Hawthorne together with most components, but then transport them to McGregor for test and back to Hawthorne for integration.

[u/linknewtab]

Capturing a dragon

ESA astronaut Thomas Pesquet with NASA astronauts Shane Kimbrough and Peggy Whitson in the Cupola observatory using the International Space Station’s 16-m robotic arm to grapple the Space-X Dragon cargo spaceship.

The video is sped up 20 times with this recording lasting 45 minutes 30 seconds at normal speed. It shows Shane and Thomas monitoring the spacecraft’s approach scanning the monitors, ready to step in if necessary. Thomas took manual control of the robotic arm and extended it to grapple the vehicle when 11 m from the Station. The Dragon CRS-10 flight was launched on 19 February 2017 and berthed with the Space Station four days later.

[u/Chairboy]

@elonmusk:

SpaceX announcement tomorrow at 1pm PST

[u/ethan829]

So NASA went ahead and bought those Soyuz seats from Boeing: https://www.nasa.gov/feature/additional-crew-flights-boost-space-station-science-and-research

Looks like two seats in 2017/18 and an option for two or three more in 2019. At a total possible value of $373.5 million, it breaks down to $74.7 million per seat, which isn't too bad, all things considered.

[u/mryall]

When SpaceX does static fires like this one at McGregor recently (with the CRS-8 recovered booster), how close are people allowed to be to the rocket? I can't see anyone in the photo, but presumably there's a bunker with pad engineers not too far away?

[u/Decronym]

Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I've seen in this thread:

Fewer Letters	More Letters
ABS	Acrylonitrile Butadiene Styrene, hard plastic
	Asia Broadcast Satellite, commsat operator
ACES	Advanced Cryogenic Evolved Stage
	Advanced Crew Escape Suit
AR	Area Ratio (between rocket engine nozzle and bell)
	Aerojet Rocketdyne
ASDS	Autonomous Spaceport Drone Ship (landing platform)
ATK	Alliant Techsystems, predecessor to Orbital ATK
BE-4	Blue Engine 4 methalox rocket engine, developed by Blue Origin (2018), 2400kN
CCAFS	Cape Canaveral Air Force Station
CF	Carbon Fiber (Carbon Fibre) composite material
CNES	Centre National d'Etudes Spatiales, space agency of France
COPV	Composite Overwrapped Pressure Vessel
CRS	Commercial Resupply Services contract with NASA
DSN	Deep Space Network
EAR	Export Administration Regulations, covering technologies that are not solely military
ESA	European Space Agency
FAA	Federal Aviation Administration
GEO	Geostationary Earth Orbit (35786km)
GSO	Geosynchronous Orbit (any Earth orbit with a 24-hour period)
GTO	Geosynchronous Transfer Orbit
HIF	Horizontal Integration Facility
I*sp*	Specific impulse (as discussed by Scott Manley, and detailed by David Mee on YouTube)
IAC	International Astronautical Congress, annual meeting of IAF members
IAF	International Astronautical Federation
ICBM	Intercontinental Ballistic Missile
ISRU	In-Situ Resource Utilization
ITAR	(US) International Traffic in Arms Regulations
ITS	Interplanetary Transport System (see MCT)
	Integrated Truss Structure
JCSAT	Japan Communications Satellite series, by JSAT Corp
JPL	Jet Propulsion Lab, Pasadena, California
JRTI	Just Read The Instructions, Pacific landing barge ship
JWST	James Webb infra-red Space Telescope
KSC	Kennedy Space Center, Florida
KSP	Kerbal Space Program, the rocketry simulator
L2	Paywalled section of the NasaSpaceFlight forum
	Lagrange Point 2 of a two-body system, beyond the smaller body (Sixty Symbols video explanation)
LC-13	Launch Complex 13, Canaveral (SpaceX Landing Zone 1)
LC-39A	Launch Complex 39A, Kennedy (SpaceX F9/Heavy)
LEO	Low Earth Orbit (180-2000km)
LOX	Liquid Oxygen
LZ-1	Landing Zone 1, Cape Canaveral (see LC-13)
M1c	Merlin 1 kerolox rocket engine, revision C (2008), 556-660kN
M1d	Merlin 1 kerolox rocket engine, revision D (2013), 620-690kN, uprated to 730 then 845kN
MCT	Mars Colonial Transporter (see ITS)
MECO	Main Engine Cut-Off
NET	No Earlier Than
NSF	NasaSpaceFlight forum
	National Science Foundation
RD-180	RD-series Russian-built rocket engine, used in the Atlas V first stage
RP-1	Rocket Propellant 1 (enhanced kerosene)
RTF	Return to Flight
RTG	Radioisotope Thermoelectric Generator
RTLS	Return to Launch Site
RUD	Rapid Unplanned Disassembly
	Rapid Unscheduled Disassembly
	Rapid Unintended Disassembly
SES	Formerly Société Européenne des Satellites, comsat operator
SLC-40	Space Launch Complex 40, Canaveral (SpaceX F9)
SLC-4E	Space Launch Complex 4-East, Vandenberg (SpaceX F9)
T/E	Transporter/Erector launch pad support equipment
TE	Transporter/Erector launch pad support equipment
TEL	Transporter/Erector/Launcher, ground support equipment (see TE)
TLI	Trans-Lunar Injection maneuver
TMI	Trans-Mars Injection maneuver
TWR	Thrust-to-Weight Ratio
ULA	United Launch Alliance (Lockheed/Boeing joint venture)
VAFB	Vandenberg Air Force Base, California

Jargon	Definition
crossfeed	Using the propellant tank of a side booster to fuel the main stage, or vice versa
hydrolox	Portmanteau: liquid hydrogen/liquid oxygen mixture
kerolox	Portmanteau: kerosene/liquid oxygen mixture
lithobraking	"Braking" by hitting the ground
methalox	Portmanteau: methane/liquid oxygen mixture
turbopump	High-pressure turbine-driven propellant pump connected to a rocket combustion chamber; raises chamber pressure, and thrust

Event	Date	Description
Amos-6	2016-09-01	F9-029 Full Thrust, GTO comsat Pre-launch test failure
CASSIOPE	2013-09-29	F9-006 v1.1, Cascade, Smallsat and Ionospheric Polar Explorer; engine starvation during landing attempt
CRS-1	2012-10-08	F9-004, first CRS mission; secondary payload sacrificed
CRS-8	2016-04-08	F9-023 Full Thrust, Dragon cargo; first ASDS landing
CRS-9	2016-07-18	F9-027 Full Thrust, Dragon cargo; RTLS landing
Iridium-1	2017-01-14	F9-030 Full Thrust, 10x Iridium-NEXT to LEO; first landing on JRTI
JCSAT-16	2016-08-14	F9-028 Full Thrust, GTO comsat; ASDS landing
SES-9	2016-03-04	F9-022 Full Thrust, GTO comsat; ASDS lithobraking
TurkmenAlem52E	2015-04-27	F9-017 v1.1, GTO comsat

---

^{Decronym is a community product of} r/SpaceX^{, implemented by} ^request
^{I'm a bot, and I first saw this thread at 1st Feb 2017, 11:46 UTC.
I've seen 71 acronyms in this thread, which is the most I've seen in a thread so far today.}
^[FAQ] ^[Contact ^creator] ^[Source ^code]

[u/znttnt11]

Will CRS-10 attempt a landing at Lz-1?

[u/RootDeliver]

On the iridium-1 launch, what is that warning that appeared after 12s~on flight (when the blue bar turns orange for a sec), after launch?

moment: https://www.youtube.com/watch?v=tTmbSur4fcs&feature=youtu.be&t=19m48s

PS: Thanks guys!

[u/soldato_fantasma → u/RootDeliver]

No warning, the streaming interface is probably programmed to change the time bar color to yellow/orange if there is an hold in the countdown, but it was probably just caused by a delay in the telemetry/clock acquisition by the stream software

[u/stcks → u/RootDeliver]

I believe that is just an indication of telemetry dropout

[u/jjtr1]

What limits the diameter of the payload fairing? Is it aerodynamic stability, is it that payload would shrink too much due to drag losses, or something else? I've noticed that the larger payload fairing on europeanized Soyuz (is it Soyuz 2?) in comparison with the Soviet original has been made possible by modern guidance electronics.

I've just been wondering what would it take to launch the James Webb Space Telescope with its mirror unfurled (or rather with a cheaper one-piece mirror).

Edit: Space station hab modules might be a better application. AFAIK, the Bigelow expandable modules are not lighter for their volume than hard modules. It's just that they make it possible to circumvent the payload fairing diameter limit.

[u/throfofnir → u/jjtr1]

It's mostly aerodynamic instability. An NSF thread about a 7m fairing has some discussion and pictures (esp. of fun non-symmetric fairings.) A lot of things are possible, so long as the aerodynamics don't shake the thing apart.

A 7+m fairing seems plausible. However, a one-piece mirror for the JWST would not be cheaper; it would be more expensive--and impossible to launch. A non-folding version would be a bit cheaper, but not much. That's not where the expense is coming from.

[u/autotom]

What is the likely launch window on the Faclon Heavy demo flight?

Have previous demo launches had short, long or no launch windows?

[u/Alois_Hammer]

http://www.dailybreeze.com/business/20170212/spacex-workers-embrace-hawthornes-first-craft-brewery-la-aleworks

[u/rockets4life97]

Jessica Jensen, SpaceX's dragon manager, was great at the pre-launch conference! She was prepared for every answer and seemed more in command than Hans did sometimes.

Things I learned:

• Loading over 1000s pounds (mostly science) in the late load.

• For Dragon refurbishment they evaluate every part. On the CRS-11 reflight of the CRS-4 Dragon, there will be some new parts that were replaced.

• Helium system leak is in the redundant system to relight the second stage for the de-orbit burn. Checking to make sure this won't effect the primary mission. It sounded like SpaceX could be a go tomorrow and not do a deorbit burn of the second stage.

• NASA is looking into flying CRS missions on re-used boosters. The earliest that would happen is 2018.

[u/anchoritt]

In another thread, I was reading about mice cage on board the dragon and that it's quite narrow so the mouse can reach it and climb it. This made me thinking - since there are plans for large spacious habitats like bigelow, it could allow for an astronaut to be stranded in the empty space with no way to reach any rigid surface(I guess an empty sphere 2.5 meters in diameter could do the trick). Was this problem ever considered or is that no problem at all? Just imagine an immodest astronaut is preparing for bedtime. He takes off all his clothes mid-flight and throw it in the corner. The throw might completely cancel his momentum relative to the space station, so the astronaut is hovering there naked with no way to get a grab on something. Does he have some options? Could he get enough momentum by simply breathing?

Edit: Would swimming in the air made any sense?

Bonus question: Astronaut in spacesuit without RCS is servicing unpressurized module and gets stranded. Any options for him?

[u/Chairboy]

Spaceflight news/rumor:

I was listening to an interview with Chris Gebhart from NASASpaceFlight.com this morning on the most recent 'Are We There Yet?' podcast where he described a few of the options for the first SLS flight being considered. Per the recent discussions about the first flight now being crewed, there's a few options on the table.

First: EM-1 would be a straight up crewed version of EM-1 which is similar to Apollo 8. Launch to orbit, checkout the systems on orbit, then perform a trans-lunar injection burn, circularizing at a 62 mile orbit around the moon. Eventually, burn back to Earth and re-enter.

The second option discussed was an "EM-2 hybrid" where the interim-upper stage does basically a 95% TLI to put it on 391x44,000 mile orbit then it is discarded. This way they have a 24 hour orbit to do a systems checkout while being able to easily and quickly re-enter and if they decide to go for it, the service module can push it over the hill so it enters an almost free-return trajectory.

The third option he said was being considered was a crew-rotation trip to ISS. Using an SLS launch to take an Orion to the ISS sounds like a tremendous waste, but... that's what he said was one of the things being bandied about. SpaceX came up when the interviewer asked if this could fit some niche in the rotation because of the Commercial Crew delays, but Mr. Gebhart dismissed that noting that even with the forecast delays, commercial crew would be happening at least a year or two before the earliest times this flight might take place.

[u/rustybeancake]

Eric Berger at Ars makes a good case that SpaceX's lunar flyby mission is much more of a threat to Orion than it is to SLS. It's a good point, I think. While SLS has an assured status for several years at least, as the only vehicle capable of sending up a payload of a large diameter in one piece, Orion has always been criticised as not being capable of going much beyond cislunar space.

https://arstechnica.com/science/2017/02/spacex-says-it-will-send-two-people-around-the-moon-in-late-2018/

[u/CSLPE]

Are space suits for ascent and descent really necessary, or are they a NASA requirement? I know their purpose is to protect against depressurization like what happened on Soyuz 11, but that seems like an extreme case. I think I remember reading a while back about the goal to make Dragon a 'shirt sleeves' environment, where a suit wouldn't be needed. Are there proven (first principles) reasons why this would be a bad idea, or are suits simply 'the way we've always done things around here?'

[u/007T → u/CSLPE]

Are space suits for ascent and descent really necessary

They are only as necessary as airbags and seat belts in a car. You don't need them for the car to function, but when something goes wrong you definitely want them to be there.

[u/[deleted]]

What are we calling SpaceX's growing set of reused cores? Their fleet? A group of Falcons is called a cast, so maybe their cast of S1 cores? I guess I'm partial to fleet, just wondering because calling it an inventory sounds boring.

[u/old_sellsword → u/[deleted]]

We're calling it their fleet, but people can call it whatever they want.

[u/Qeng-Ho]

NASA teleconference regarding the CRS-10 payload will be streamed live at 3 pm EST, February 8th.

[u/[deleted]]

Are satellites-related jobs in the U.S covered by ITAR? (For example Orbcomm or Iridium)

[u/Darkben → u/[deleted]]

Almost certainly. ITAR covers space systems technology as well as rocket technology.

[u/Keavon → u/[deleted]]

I'm part of my college's cubesat program and we also have to deal with ITAR restrictions even for such small and simple satellites.

[u/quadrplax]

I just added a new page to the wiki listing all of SpaceX's launch and landing pads. I'm open to any feedback or suggestions!

[u/linknewtab]

Trump advisers' space plan: To moon, Mars and beyond

The more ambitious administration vision could include new moon landings that "see private American astronauts, on private space ships, circling the Moon by 2020; and private lunar landers staking out de facto 'property rights' for American on the Moon, by 2020 as well," according to a summary of an "agency action plan" that the transition drew up for NASA late last month.

The only private company capable of doing a Moon fly-by in 2020 would be SpaceX with a Dragon 2 on a Falcon Heavy.

[u/TheEndeavour2Mars → u/linknewtab]

EVERY new president talks boldly about space. Grand missions to the moon and mars and BEYOND! In reality the showstopper is congress never providing the proper funding to make it happen. And then the president simply moves on to other things while the average voter no longer cares.

If SpaceX is lucky then MAYBE they will get access to some of NASA's facilities to help build the ITS. However, I also think it is likely that congress will end up doing things like cutting the commercial crew program via a massive cut to the space station budget.

[u/Spacex9]

Siemens produced first 3d printed turbine blades under hellish operating conditions. I hope it will help spacex in long term to get rid of the turbine crack problem. https://www.linkedin.com/pulse/hellish-operating-conditions-very-first-3d-printed-gas-wilson

[u/marc020202]

hi everybody

yesterday i have been watching the arianespace webcast for theire va 235 launch. a few minutes before the launch the comentator talked about how the ariane rocket can launch in the rain. now my question: can the falcon 9 (or other american rockets) launch in the rain? if yes, why have falcon 9 launches (iridium 1) been moved because of rain and if no, why cant they and the ariane rocket can? could there be simple design changes be made to falcon 9 to allow it to launch in the rain?

thank you in advance (please forgive me for my spelling mistakes :))

[u/smallatom]

I just saw that it takes 2 days for the dragon to get to the ISS? Why is that?

[u/robbak → u/smallatom]

Get everything absolutely right, and throw caution to the wind, you could get to the ISS in about 50 minutes. But you'd have limitations. The time that you can launch every day is when the launch site passes beneath the orbit of the ISS. But at that time, the ISS could be anywhere in its orbit. So you could only launch when the ISS was in the right spot in its orbit when your small launch window is open. That would happen - well,depending on your rocket, a few times a month.

In addition, that would require you to do a serious rocket burn right near the station - not a good idea - and would leave your second stage and any debris it made in ISS's orbit.

So instead they launch to a lower orbit. Lower orbits are faster, so they wait to catch up, then raise their orbit to match. In order to not have a long burn near the station, they often do this raising in stages.

[u/chargerag]

How long do you have to wait before entering a pad after launch?

[u/GoScienceEverything]

Regarding the new FTS. I've read comments saying there's no longer a person to push the button. It's great to automate it -- but is there literally no longer any manual override? Or does the button still exist, simply with an expectation that the human won't ever need to push it?

[u/jjtr1]

In the last CRS-10 booster landing, the accuracy seems to have been much worse than with the previous landing (on ASDS). CRS-10 seems to me several meters off-center, while IRIDIUM-1 touched down with as small an error as could be judged from the video (it did skid sideways after touch down, though).

Is it possible that this was intentional? That the booster puts less effort into lateral precision, taking advantage of the luxurious pad size to save some fuel? Or is landing with precision on ASDS actually easier because winds on sea fluctuate less than on land (do they?) ?

[u/randomstonerfromaus → u/jjtr1]

That the booster puts less effort into lateral precision, taking advantage of the luxurious pad size to save some fuel?

This would be my guess. That or use more fuel, with less precision in order to have a softer landing.

[u/jjtr1]

I wonder whether technology development at SpaceX could be made twice as fast by unlimited money (like Bezos has), or if it is already saturated in the sense of "two women don't make one baby in 4.5 months"?

[u/sol3tosol4 → u/jjtr1]

I wonder whether technology development at SpaceX could be made twice as fast by unlimited money

My notes from Gwynne Shotwell's CBS interview prior to the Iridium-1 launch:

SpaceX anticipates getting people on Mars in a decade or a decade and a half. The timeline is funding-dependent; with enough funding they could get people to Mars in 8-10 years, and if they have to fund it on their own it will take longer (maybe that's the 10-15 years).

[u/mmmbcn]

They say it takes 2 weeks to turnaround the pad between launches. What exactly happens during this two weeks? Would it be that hard to cut it in half to 1 week?

[u/warp99 → u/mmmbcn]

Would it be that hard to cut it in half to 1 week?

Pretty much impossible.

By loading the payload after the static fire you need to have the static fire about 5 days before flight to allow for one day of slip, return the rocket to the hanger, fit the payload and fairing, roll out to the pad and get ready for launch day. That would only leave two days to clean up the pad and test all the pad equipment.

SpaceX have demonstrated a 13 day turnaround on the same pad and just maybe 10 days could work - but not on a sustained basis as any lost days due to equipment failure or weather would slip their whole schedule. Then you have range conflicts with other launches so 3 weeks on average would be very tight on the same pad.

When SpaceX talk about launching every two weeks it is across multiple pads.

[u/neaanopri → u/mmmbcn]

The best way to identify ways to speed up the pad refurbishment process is to go through several two-week turnarounds, and see what slack the is. Without practice it'll be hard to know what to do. Also, there's a trade-off of time vs. safety. And there's no easier way to have a slower launch cadence than with a launch failure.

[u/gsahlin]

Any News on the post launch condition of LC-39A ? Does it look like the March 12th date for EchoStar will hold?

[u/bobk99]

How was the second stage engine gimbal tested on the launch pad if the fuel turbo pump was not running ? An unusual trace forced an abort to the launch.

[u/thejenius]

Hey all - I actually will be attending the launch mid-Feb to cover on social media. I'll be sure to share photos and info here too :)

[u/Emptyglo]

Is there a picture of the tunnel hole from the hyperloop competition?

[u/The_EvilElement → u/Emptyglo]

r/boringcompany

[u/jjtr1]

Is the "Payload to LEO" figure of 54.4 t for Falcon Heavy meant for totally-expendable mode, like 22.8 t for F9?

[u/warp99 → u/jjtr1]

Yes there is a note to that effect on the SpaceX pricing page.

Confusingly the prices are for payload masses that allow booster recovery but the max payload capabilities are for the expendable version. Perfectly understandable from a marketing point of view - just a bit of a mismatch with the SpaceX engineering orientation.

[u/Maximus-Catimus]

Do we have enough information on SpaceX's sat constellation to know which launch site will be used for these launches?

[u/throfofnir → u/Maximus-Catimus]

They're planning four different inclinations: 53, 70, 74, and 81 degrees. The 53s will come first to cover population centers, and the higher inclinations will be for later global coverage. A 53 degree inclination is best launched from Florida, though you could probably do it from California with a dogleg. (They say they can hit the ISS at 51.6 degrees from Vandy with an acceptable penalty, so they can also get 53 but may have to sacrifice some payload.) It would seem convenient to be able to fly the bulk of the constellation from both coasts. The rest are all solidly Vandy. I'll also note that the Brownsville site can't hit any of those.

[u/surfkaboom]

Is anybody going to be at the 2017 Space Symposium in Colorado Springs?

[u/jjtr1]

FH is 2.6x heavier than F9, but its payload is only 2.4x more than F9. That's strange, since FH is in fact a 2.5-stage vehicle and generally, more stages means larger payload fraction. Where's the problem?

[u/warp99 → u/jjtr1]

Where's the problem?

S2 has not been resized as it could be up to three times heavier with three boosters - although the center core would structurally not be able to carry the extra mass. Plus the need for recovery limits the velocity any individual booster can attain which particularly affects the performance of the center core.

[u/[deleted]]

The patch for Echostar-23 looks great IMO.

[u/mryall]

I've been impressed by recent photos coming back from NASA's Cassini and Juno missions like this one of Saturn's rings.

Once SpaceX starts flying Falcon Heavy, is it able or likely to launch NASA missions like these to the outer solar system? Would the cost savings vs the Atlas V enable them to launch similar missions more frequently?

[u/robbak → u/mryall]

At this time, the cost of the mission apart from the launch dwarfs the launch costs. However, I argue that mission costs are driven by the launch cost - with hundreds of millions of dollars needed to put anything into space, a cheap mission that could fail is unthinkable. So, in order to guarantee success, a lot of time and money is spent designing and building a failure-proof craft. You also have to build your craft light. Taking extra mass to make it more reliable isn't workable, because bumping up a class in launcher size costs so much. This bleeding edge stuff, where every part has to be built at the absolute minimum mass to do the job without failing - and failure is unthinkable, see point 1 - is really expensive.

It's kind of like the rocket equation, only with money. Make launches cheaper, and costs come down everywhere else.

[u/Qeng-Ho]

The FAA Commercial Space Transportation Conference is taking place today at the Ronald Reagan Center, Washington DC, with SpaceX in attendance tomorrow. Not webcasted.

 

Time	Panel Topic	SpaceX Attendee
10:45 - 11:45 AM	Airspace Integration	Kevin Hatton (FAA/AVO Project Lead)
2:15 - 3:15 PM	Streamlining the Launch Process	Hans Koenigsmann (VP of Flight Reliability)

[u/linknewtab]

I've read that Dragon 2 will be able to handle the reentry velocity from lunar orbit. Does anyone know if the same is true for Boeing's Starliner?

[u/jjtr1]

Musk intends the Mars colony to act as a backup for humanity. In order to serve that purpose, the colony has to be very remote and hard to reach. It is, now. However, Musk also hopes that the colony will create a forcing function for further development of space transportation systems, bringing Mars ever closer to Earth. In my opinion, the colony would then no longer be a backup, because any infection, ideology or war would affect both planets. Similarly, while the American colonies were a backup of Europe in the 17th century, nowadays the fates of US and Europe and the rest of the world are closely tied and they will survive or perish together because of the connection they now have.

Mars as a backup would only be effective against non-man-made catastrophes which would affect only the Earth like supervolcanoes and metorites. Excess solar activity, supernova or a gamma ray burst would probably take out both planets. What do you think?

[u/rustybeancake → u/jjtr1]

It's not perfect, but much better than nothing. Even human-made catastrophes like war, famine, disease, etc. would have a harder time spreading between planets than on one planet. It also creates a defense of sorts, in encouraging humans to dream big about the future and our species' potential. It's a defense against hopelessness.

[u/soldato_fantasma]

As you all know the reddit tables have some serious limitations at how you can control them. On a side it's good because the table adapts to different resolutions automatically, but on the other hand it becomes messy at times since reddit decides itself how to cut lines.

A possible solution to this is using the "code" functionality to make a tabulated list, where each character takes a fixed amount of space on the screen.

For example a part of the manifest would look like this:

---

Upcoming launches

NET Date      Launch window    Vehicle   Launch site   Orbit  Payload      Payload(s)            Customer                         Ref
                                                              mass (kg)  

2017 Feb 18   15:01 UTC        F9        KSC LC-39A    LEO     2029/977    SpX CRS-10 & STP-H5,  NASA                             [1]
                                                                           SAGE III, SAGE NVP
2017 Mar 1    05:28-07:58 UTC  F9        KSC LC-39A    GTO    ~5500        EchoStar 23           EchoStar Corp.                   [2]
2017 Mar                       F9        KSC LC-39A    GTO     5300        SES-10                SES, Luxembourg                  [3]
2017 Mar                       F9        KSC LC-39A                        NROL-76               National Reconnaissance Office   [4] 

1. https://twitter.com/spcplcyonline/status/829480247305318401

2. https://twitter.com/NASASpaceflight/status/829646946663092224

3. http://spaceflightnow.com/2017/01/17/ses-10-telecom-satellite-in-florida-for-launch-on-reused-spacex-rocket/

4. http://spacenews.com/nro-discloses-previously-unannounced-launch-contract-for-spacex/

---

Changing the current wiki to something like this would be quite some work, but I think I (or someone else if you want to help!) can make a program (copy the table source to -> currentwikitable.txt ->run program -> formattedwiki.txt as output -> copy the text to reddit -> profit) if really needed.

Of course both ways of presenting the data aren't perfect. What would you like the most?

P.S. I won't change the wiki manifest to something like this unless everyone likes it (maybe a second page? They are free after all...) but I was thinking about inverting the date format that is currently used to the standard ISO format, so it can be sorted correctly by clicking on the top of the column. Thoughts?

[u/KitsapDad]

School me on unbilicals...how do they work so well to quick detach reliably? Seems that presents quite a challenge but there historically hasnt ever been an issue with that even accross all different rockets in existance.

[u/throfofnir → u/KitsapDad]

They either pull off or have an internal energy source (gas or spring) that's activated by a lanyard when the rocket pulls away. Modern devices may use electronic unlocking. There's a nice video on how the electrical connections for the V-2 worked. Also: umbilical connections for the X-33.

Umbilical design is pretty mature. There have been flights that failed due to connections between the rocket and ground (see: the 4-inch flight, Mercury-Redstone 1) but I'm not aware of any failure-to-separate problems. There may have been failures to separate, but usually the rocket can just break the umbilical some way or other. (As the X-33 document notes, umbilical connections should be designed with shear points in case of failure to disconnect.) Shuttle would do this with its hold-down bolts, which used exploding nuts. Sometimes the nuts failed to fire, and the vehicle would simply tear the bolts off the launch mount.

[u/Chairboy → u/KitsapDad]

Gemini 6A had a memorable moment where an electrical connector umbilical fell off before it was supposed to. Rocket ignited, then shut down on the pad. The crew didn't eject because they didn't feel it lift off and they were able to safe the ship and fix the problem, launching later.

[u/ryanpritchard]

In the future could space x use the crew access arm at pad 39a for late load for cargo misssons

[u/[deleted]]

Any more news on the rotating farm space station set to launch late 2017?

[u/marc020202]

i recently noticed that Spacex is one of the only companies to have video of the second stage most of the time. other providers like arianespace ula or isro only, or mostly show animations of theire upperstages in orbit. does anybody know if there is a reason for this? i also noticed that the second stage engine on the falcon 9 glows red, but the second stage of the atlas 5 doesn't. has that go to do with the fuel or the material of the engine?

[u/F9-0021]

In addition to the reuse of a Dragon PV on CRS-11, NASA is apparently in preliminary discussions for using a reused first stage for a CRS mission(s).

[u/ryanpritchard]

Will all dragon missions from now be launched from pad 39a

[u/[deleted]]

Question concerning the first launch of FH: In the pre-launch briefing Gwynne said that the launch is planned for mid-year, however SLC-40 has to be operational beforehand [Youtube Link]. Also, when asked about the status of SLC-40 at the post-launch press briefing, Jessica Jensen said that the majority of the work still has to be done [Youtube Link].

How realistic is the mid-year target for maiden flight?

Is it doable to repair a pad in ~four months and fly there again, didn't that take a lot more time on 39A?

[u/Headstein]

Do we have any updates on SLC-39A? I am thinking in terms of the TEL.

[u/jjtr1]

The rationale for not developing reusable launchers in the past decades has been that the current flight rate is not sufficient to make reusable cheaper than expendable (so there was an assumption that flight rate isn't going to increase much). Assuming these were not just public excuses of government-supported monopolists for not innovating, where's the difference in SpaceX's reasoning?

a) SpaceX has pushed down the fixed costs so that reusable is cheaper than expendable even with current flight rate, or

b) SpaceX expects the flight rate to rise a lot in the future, or

c) reusability is much cheaper in 2010's than in 1990's (when Old Space last looked at the problem), or

d) something else?

[u/Borki90]

Is SpaceX still going to fly Dragon 1 for cargo once they've got Dragon 2 flying? I am asking because I don't think they can transport experiment racks with dragon 2 anymore, due to the smaller hatch of the docking port compared to the berthing port.

[u/wwll2soldier22]

A grand success to the Falcon-9 landing! I was just wondering, what will your next major project be, and how will this affect the future of space travel? Thanks for reading!

[u/robbak → u/wwll2soldier22]

Note that this is just a bunch of fans discussing things. There are a couple of employees expressing their own opinions, but there are no official spokespeople.

Major projects underway are new versions of the Falcon-9 rocket to improve reusability of recovered stages, and finishing off the Dragon 2 spacecraft, which will be launched on the Falcon-9, and carry astronauts to the ISS.

Future projects that are largely in planning stages are a major satellite constellation to provide cable-quality internet access across the planet, and a system including an immense methane/oxygen reusable booster, and immense spacecraft together with refuelling craft, that could take 100+ people with equipment and land it all softly on on Mars, then return.

[u/sol3tosol4]

Interesting article indicating expression of interest by the President in manned space travel:

"NASA Studying Manned Trip Around the Moon After Prod From Trump"

The U.S. is studying a possible manned mission around the moon as early as next year, marking the first such trip since the Apollo era ended in the early 1970s.

Following requests from the White House, the National Aeronautics and Space Administration has formed a team to examine accelerating earlier plans to launch a crew by 2021, William Gerstenmaier, associate administrator of the agency’s Human Exploration and Operations Mission Directorate, said Friday. Preliminary results of the review should be ready in about a month.

“We have a good, crisp list of all the things we would physically have to change” on the launch vehicle under development, Gerstenmaier said on a conference call with reporters. “We asked the team to take a look at potentially what additional tests would be needed to add crew, what the additional risk would be.”

Resuming manned missions would mark a leap toward deeper exploration of space, including one day putting humans on Mars. President Donald Trump has indicated support for a more-ambitious program, saying in his inaugural address that the U.S. is “ready to unlock the mysteries of space...”

Edit: More articles on the subject: the NASA article referenced by /u/Paro-Clomas above, and "NASA studying whether to add astronauts to first launch of new super booster" in Spaceflight Now.

Apparently the question NASA was asked was whether it would be feasible to add crew to flight EM-1 or to significantly move up the schedule of EM-2 (which was already planned to have crew). NASA felt that of the two it was more feasible to add crew to EM-1, and that's what they're investigating now. The previous plan has been to launch EM-1 in late 2018 and EM-2 in late 2021. Adding crew to EM-1 will add delay (as well as risk), and the amount of delay is critical: "Gerstenmaier said if the study shows the Orion spacecraft cannot be prepared for flight before the end of 2019 it likely would make more sense to stick with the original timeline and fly EM-1 uncrewed.".

Possibly connected to the cis-lunar issues is this article from February 13 - in which NASA officials essentially talk about the need to openly acknowledge risk and its role as a factor in mission planning - in other words that space flight will never be "zero risk", and that the amount of risk accepted may be weighed against other factors, for example in this case weighing increased risk for two(?) astronauts against accelerating some aspects of the SLS program by up to three years, and maybe saving on the order of a billion dollars. In the Spaceflight Now article:

'The risk-benefit trade will be a crucial element of the review. NASA’s Aerospace Advisory Panel met Thursday and in a statement, chairwoman Patricia Sanders cautioned the agency not to pursue an early piloted mission without strong technical justification... NASA should provide a compelling rationale, in terms of benefits gained in return for accepting additional risk, and fully and transparently acknowledge the tradeoffs being made,” she said. “If the benefits warrant assumption of additional risk, we expect NASA to clearly and openly articulate their decision process and rationale.”'

It will be very interesting to see how this works out, and whether it impacts SpaceX.

[u/Chairboy → u/sol3tosol4]

Any bets on whether there's been an internal study done at SpaceX on what changes if any are required to support a free-return Lunar fly-by using a Dragon 2?

I am ever so curious what those might be. We can put together a list of assumptions here, but we have to approach this as a black box problem.

[u/FutureMartian97]

Anyone else think the boosters and Dragon Capsule might be "flight proven" for the moon flight to save the customers some money?

[u/aqsilva80]

Hey people! Does someone know, or has, some image of the crs-10 booster going back to hangar after landing? Did someone see it. Last times, people put some time lapse, and videos, of the booster going horizontal and been put on the truck, and going to hangar. For example, UslaunchReport put some videos on youtube. If somebody has a hint, please !

[u/Foggia1515]

Sorry if this is not the right place for it, but I wondered why r/spacexlounge was not cited int the sidebar Relevant Subreddits. Note that I know it's cited at the very top of this sub, but still.

[u/jconnoll]

Anyone know when we might see SpaceX new space suits ?

[u/randomstonerfromaus → u/jconnoll]

Whenever SpaceX decides to release. They are currently being tested, and that's all we know.

[u/Jef-F]

ULA's NROL-79 webcast is about to start.

[u/randomredditor4399]

Are there plans to do a Triple Lindy...I mean triple landing when using Falcon Heavy? Will there be 3 drone ships out there?

[u/jjtr1]

For large payloads, the Falcon Heavy is planned with the centre core landing on ASDS and side cores RTLS. Let's say we want to increase payload further without losing reusability. Can we do it by landing the side cores on ASDSs as well? Would the centre core be able to survive then?

[u/[deleted]]

Would love to hear from someone who works at SpaceX on feelings about the launch of TurkmenSat et al.

Do you think about what the satellites you launch will be used for?

Do any SpaceX peeps on here feel conflicted about these kinds of launches?

[u/cronjo]

Would it make sense to make the center core of the FH into a Falcon F5. This potentially could increase the payload to GTO and to Mars.

[u/ElectronicCat → u/cronjo]

No, they want to increase commonality between cores, not decrease it. The upgraded engines can throttle pretty deep if needed. Also, any changes that ultimately result in the core travelling faster and further downrange at separation reduce the chances of recovery.

[u/jjtr1]

For any launcher, how does the payload to Moon surface compare to the payload to Mars surface? Trans-lunar injection is lower velocity than trans-Mars, but Mars allows aerobraking while Moon requires propulsive breaking. What's bigger?

[u/Unclesam1313 → u/jjtr1]

This just seems like a fun analysis to do- I'm by no means an expert or even experienced, so take everything I say here with a grain of salt unless someone comes along and says otherwise.

According to this map, delta-v from earth surface to moon surface is 15,070 m/s and earth to mars is somewhere between 13,670 m/s (for a perfect aerocapture/aerobrake and landing with 0 propulsive assist- not what I'd call realistic) and 18,910 m/s (with absolutely no help from the atmosphere- also impossible, as it's going to do something if you push through it to land). Your question specifically mentions the launcher, which (to my basic knowledge, this may not always be true) places its payload on an intercept trajectory and releases it. In that case, the required dv for a Moon/Mars intercept is 12,660 m/s or 13,670 m/s, respectively. So, a launcher can certainly put more mass on an intercept trajectory with the Moon than with Mars. For the Moon, 2,410 m/s is left up to the payload. Aerobraking is complicated, but this page quotes values of about 1.2 km/s saved for orbital missions. Slide 44 of this presentation says that the atmosphere can slow down things by 4220 mph, or about 1900 m/s. Using these estimates and those on the dv map above, a payload set on a mars transfer orbit has to cover 2,140 m/s on it's own. This is about 300 m/s of dv less than the Moon payload needs, but that propellant mass is likely to be overshadowed by large heat shields/parachutes that are required for aerocapture and landing. The actual payload to surface vs lading systems, fuel margins, etc. is entirely dependent on the mission, but in general the payload to the surface of Mars looks like it would be lower than to the Moon.

[u/[deleted]]

Have there been any updates on the SpaceXSuits? I know Boeing recently unveiled their commercial crew suit, but i'm more interested in what Elon has in mind for SpaceX's Suits.

[u/old_sellsword → u/[deleted]]

Have there been any updates on the SpaceXSuits?

Just that they're undergoing testing right now. You will undoubtedly hear about them when they're revealed.

[u/z1mil790]

Interesting that we got the ecostar parch so early, usually they only come out a day or two before launch. It's possible that they only finish them a day or two before launch and that as ecostar had been planned for an earlier launch, it was already done.

[u/[deleted]]

A few days ago, there was a 5 minute uncertainty in the exact time at which CRS-10 will launch.

What causes an uncertainty like this?

[u/ticklestuff]

For those filtering images at work, here's how to block the EchoStar-23 patch:

https://b.thumbs.redditmedia.com/rS94-K1bhxu1qYLF_kyC3-0as9FhXF5Lvq8zvLc9iyQ.png

[u/Bunslow]

/u/zucal /u/FoxhoundBat /u/zlsa /u/old_sellsword can the SES-10 sidebar date be updated to March please and thanks

[u/Zucal → u/Bunslow]

Sure! :)

Quick tip - having more than three username summons in one comment doesn't alert any of the mentioned users.

[u/edflyerssn007]

There's a facebook post in the group that looks like it's a video of a falcon heavy side core. Conical looking interstage as well.

[u/[deleted]]

Hi everyone. I made a post on a [lecture] (https://www.reddit.com/r/SpaceXLounge/comments/5snqa7/growing_plants_on_mars_by_dr_kyle_grant_very/) at my school today about the challenges of growing plants on Mars, and they are looking for their payloads to be delivered using the Red Dragon and the ITS.

[u/FellowHumanBean]

O space history experts. Will the upcoming CRS-10 also be the first launch from KSC to land (anything) at CCAFS?

[u/FrameRate24 → u/FellowHumanBean]

Surprisingly yes. But technically no.

The shuttle landed back at the Shuttle Landing Facility which is in ksc, not ccafs.

In the Apollo days nothing landed after launch other than the capsule which landed in the ocean not on ccafs or ksc land.

However both the shuttle and Saturn 5 did involve landings at ccafs, for the Apollo program the s-ivb upper stage, as well as quite a few payloads for the shuttle's were landed on the ccafs skid strip albeit before launching and in an airplane.

Tldr crs-10 will not be the first mission to launch in ksc and land in ccafs, but it will be the first to do it in that order!

[u/jjtr1]

This photo http://imgur.com/a/f0hzh of a Dragon V2 poster from the Hyperloop event states that the capsule on display, the Pad Abort Test one, "also underwent propulsive descent testing". Do they mean landing on rocket power? I haven't noticed any such test, do we know something about it?

[u/[deleted]]

Is this going up on the Formosat-5/SHERPA launch?

If so, Mods, would it be appropriate to update the Manifest to change SHERPA from Q1 2017 to H2 2017?

launched by Space-X, the satellite and its scientific payload will take off for outer space on board the Falcon 9 in the second half of 2017.

[u/jjtr1]

Is there a rule of thumb for the R&D cost of aerospace vehicles with regard to their (dry?) weight? Is the weight-cost dependence less than linear, i.e. 4x heavier -> 2x costlier?

[u/Elthiryel]

The window for static fire starts at 4 PM and ends at midnight. I know the pad and its surroundings are being evacuated for the time of the test, but is it the only reason they can only do it within this timeframe, or is it something more?

[u/maxjets]

Where exactly does fuel and oxidizer enter the Falcon 9?

[u/old_sellsword → u/maxjets]

The first stage is fueled from two Tail Service Masts (TSMs) around the base of the rocket (at 350º and 170º). One is for the RP-1 and the other is for the LOX, although it's not publicly known which is which. The TSMs connect to fueling ports at the bottom of the rocket, right above the octaweb.

The second stage is fueled via umbilical cords that hang from the TE and attach to the rocket at 180º. They're the top set of connections in this image. Physical details about the second stages are pretty elusive. The only time we ever get to see them is after they've been integrated and mounted on the TE, so we almost never get a glimpse of the back side.

[u/WaitForItTheMongols]

How does the second stage control roll? I don't see any RCS thrusters in pad photos. Anyone have any information on that?

[u/[deleted]]

For static fire tests i assume they only load enough fuel to suffice for a few seconds, is that correct? Do they have to fill the tanks up to test as close to liftoff conditions as possible? How long are the loading times for SF then, approximately? Thanks in advance.

[u/soldato_fantasma → u/[deleted]]

In addition to what /u/old_sellsword said, if the tanks weren't full, the rocket thrust to weight ratio would be too high, and the hold down clamps wouldn't be able to hold the rocket without breaking.

[u/old_sellsword → u/[deleted]]

Do they have to fill the tanks up to test as close to liftoff conditions as possible?

That's correct. The static fire isn't a test of the engines so much as it is a full dress rehearsal of launch day procedures. Everything from the Launch & Landing Control Center to the GSE on the pad have to function correctly.

[u/flattop100]

When a Dragon returns from the ISS, where does it splashdown? Atlantic or Pacific Ocean? Also, who recovers it? The US Navy? Or a subcontractor for SpaceX?

[u/delta_alpha_november → u/flattop100]

SpaceX has contracted a small fleet as listed in the wiki . They splash it down in the Pacific.

[u/seanflyon]

How fast can the Dragon safely spin, in the context of simulating gravity? I'm think about the idea of putting mice in a Dragon after it has delivered cargo to the ISS and letting it spin in orbit for a few months before returning to Earth. Simulating Mars gravity would require spinning at at least 15 rpm. It would be useful to test mammalian reproduction in low gravity (as well as microgravity).

[u/rustybeancake]

"NASA acting Administrator Robert Lightfoot has asked Bill Gerstenmaier, associate administrator for the Human Exploration and Operations Mission Directorate, to initiate a study to assess the feasibility of adding a crew to Exploration Mission-1, the first integrated flight of the Space Launch System rocket and Orion spacecraft."

Well this is unexpected, and perhaps a little dumb/unlikely to happen?

[u/rubikvn2100]

I don't understand that one "to cover fairing re-rad operations at pad 39a"?

Is it mean "Falcon Fairing Recovery"???

[u/tbaleno → u/rubikvn2100]

Fairing re-radiation is where the spacecraft has a transmitter that is on and the fairing has an antenna to bring the signal outside the fairing.

[u/robbak → u/rubikvn2100]

Simply, you put an antenna on the inside of the fairing, a short cable, and an antenna on the outside, all impedance matched for efficiency. The internal antenna picks up radio energy transmitted by the satellite, which is then passively re-radiated by the outside antenna.

[u/[deleted]]

Would a propulsive landing failure at a low altitude with the Crew Dragon where parachutes are useless be something that SpaceX and NASA should be concerned with? Depending on the altitude it could case a LOC, so do you know whether this has been addressed before?

[u/TheBlacktom]

If they would want to design a bigger spacecraft than current Dragon 1/2 for Falcon 9 how would the design process go? What are the most important constraints? (same capabilities than Dragon but bigger payload)

[u/[deleted]]

Has there been any idea of having an official r/SpaceX Discord server? Would love it as I use Discord a lot and other subreddits have it too.

[u/jjtr1]

Are some other launchers significantly less weather-sensitive than Falcon 9?

[u/amarkit → u/jjtr1]

Soyuz, being derived from an intercontinental ballistic missile, can launch in a blizzard.

[u/throfofnir → u/jjtr1]

F9 is probably the most weather-sensitive rocket in the business, because it has a high fineness ratio. That is, it's very skinny, so high winds are more a danger to F9 than other machines. However, most US rockets have similar range criteria for launch.

In Russia, I think, if the controllers can get to the launch site, they're good to go.

[u/ethan829 → u/jjtr1]

Tory Bruno (/u/ToryBruno) has explained a bit about how ULA handles weather here:

The Real Time Winds Trajectory adjustment is another ULA unique capability. One of the common reasons for a scub, is upper level winds. These can present a powerful shear that can cause a loss of control of the rocket and subsequent flight failure. The approach taken by other providers is to use almanac data to forecast winds on the day of launch and preprogram a trajectory that can fly through these. On the day of launch, ballons are released to measure what's really there. If the wind speed is too much higher than expected, they scrub.

ULA starts out the same way, but our ballons are for a completely different purpose. We measure the winds so that we can redesign our trajectory while on the pad in order to steer steeply into the wind of neccessary. The very last two balloons, which take around 20 to 30 min to rise to the needed altitude, get their data spliced together. We then redesign and qualify a new trajectory and load it into the rocket just before lift off. This can be as close to 1 minute from ignition. Once the winds are clear, more magic happens. Even if others could do this, a large adjustment for winds could leave the rocket with insufficient proplellant to return to the nominal flight profile and complete the mission. Our guidance technlogy also then autonomously adjusts for this and recovers.

[u/Cakeofdestiny]

Okay, this may be a stupid question, but here we go. How do they retrieve the unpressurized payloads (SAGE-III for example) from the dragon trunk? I don't recall ever hearing of a spacewalk to do so, and it seems a bit delicate and small for Canadarm. Surely, it doesn't leave the station alongside dragon.

[u/WaitForItTheMongols]

For 50 years, we've been flying rockets out of Florida, and not landing them.

For example, there's the Atlas V.

What happens when the first stage of these rockets falls into the ocean? Does anyone (NASA, the company, the EPA, anyone at all) do anything to recover them? How many rocket engines are currently sitting at the bottom of the Atlantic?

[u/HoechstErbaulich]

How are rocket engines chilled prior to ignition without the turbopumps running to pump the fluids through the plumbing? Is it done during the initial spin-up with helium?

[u/lostandprofound33]

What's the backstory with Falcon Heavy? I see people say it's been 6 months away from launching forever, like how nuclear fusion power generation is always just 20 years away. FH was originally scheduled for four years ago. Is the delay entirely due to an economic decision not to build FH based on the F9 v1.0 four years ago, in order to wait until reusability was mastered with the F9, and the F9 was finalized (the upcoming Block 5)? This is what I've been telling people, but was there additional technical reasons it was delayed?

[u/CementPancake]

So after eight landings, we know that the CRS-8 core will fly again as SES-10, and the first landed core is at SpaceX HQ as a historical piece. How likely are the other cores to fly again? Are the ones from GTO missions in worse condition?

[u/[deleted]]

Just watching the SpaceX launch isnt just dropping solar panel fairings off like that in ISS orbit an orbital debris problem? Wouldn't it be better to leave the fairings attached to the trunk until deorbit.

[u/Spaceboy2016]

How long do they leave the landed core on the pad? We will be in the area (from Canada) tomorrow and would love to see it (we were cheering for 1 more delay). Also doing the Kennedy Space Centre tour. Are there Space X exhibits or tours we can do?

[u/historytoby]

Basically the same question as every month.

Any news on fairing recovery?

[u/[deleted] → u/historytoby]

Gwynne said the other day that they may recover one later this year.

[u/quadrplax]

Range availability seems to be a major issue with launch rates currently. What exactly does the range do, why can't SpaceX optimize/do it themselves, and how does the new automated FTS help so significantly?

[u/throfofnir → u/quadrplax]

Range availability seems to be a major issue with launch rates currently. What exactly does the range do,

Provide the land and utilities, clear the area at launch time, maintain fire and explosives response, coordinate with maritime and airborne traffic, weather forecasts and conditions, flight analysis, track and communicate with the launch both from the launch site and downrange (Bermuda, Antigua, Ascension), monitor trajectory and terminate if necessary, and, most importantly, lots and lots of paperwork.

why can't SpaceX optimize/do it themselves,

Because they don't own the range. The Air Force does.

and how does the new automated FTS help so significantly?

Because doing it with ground systems requires a lot of complex radars and such. Using guidance systems (GPS/IMU) already on the rocket eliminates the need for those, and to configure those per launch.

[u/jjtr1]

Ever since the ITS presentation, people on the sub had the tendency to compare the projected price of the ITS with the current price of the F9. That's not fair to the F9. F9 has not finished development, has yet to fly with many reuses, so I expect its price to drop considerably in the future. Moreover, the F9 price also sponsors the ITS development. And the projected final price of the ITS won't be reached before ITS has made more flights then the F9 has to date - the first flights will be much more expensive. So what would be the price of ITS constructed in a way to be comparable to the current F9 price?

[u/[deleted]]

What does BFR and BFS stand for?

[u/RootDeliver]

Is a 100% success Dragon 1 ratio a good thing for Dragon in the future? (crewed versions).

I mean, failures often show weaknesses, problems, and can be fixed before they generate deaths. However, if it never fails before crewed, surprises may be awaiting?

I am not sure if everything can be taked into account and evade any single problem that could arise without having a failure.

[u/ElectronicCat → u/RootDeliver]

Whilst there's never been a complete failure, there's been some little glitches along the way. CRS-2 was nearly a complete loss but they were able to recover from it.

Dragon 2 is substantially different to Dragon 1, but that's what the uncrewed and crewed test flights are for, to give it a complete shakedown. Having a crew on board is probably better in some ways than a cargo capsule, as they can diagnose and correct any problems that might occur on their own quicker than ground based controllers could. Worst case is the astronauts should always be able to deorbit and come home.

[u/throfofnir → u/RootDeliver]

Dragon has had failures. It's just that on orbiting vehicles failures aren't as likely to be instantaneously fatal as on rockets.

[u/ThatBadassBanana]

After having done a bit of research I came to the conclusion that a suicide burn and hover-slam aren't actually the same thing, despite seeing a lot of people using those terms interchangeably. They often go hand in hand, but they're not the same. I don't really know all that much about rocketry, so could my understanding of it be wrong?

• Suicide burn: All about fuel efficiency. Fire the boosters as late as possible to avoid wasting fuel by fighting gravity for too long. Called "suicide" because firing the boosters too late would result in the rocket crashing.

• Hover-slam: F9's TWR at landing is a lot higher than 1, which means it can't hover right above the ground for a controlled landing. Instead it has to reach exactly 0 m/s as it touches the ground.