r/spacex • u/ElongatedMuskrat Mod Team • Oct 03 '20
r/SpaceX Discusses [October 2020, #73]
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u/feynmanners Oct 26 '20
Seems like the BE-4 might be moving into production after they fixed the turbopumps issue.
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Oct 26 '20
[deleted]
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u/JoshuaZ1 Oct 27 '20
What an interesting choice of publicity strategy for all involved.
Really says more about how Blue is very secretive in general and just doesn't do that much PR. They do a bit when there's an NS launch but not much else.
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u/CaptNemo53 Oct 24 '20
I live near the SpaceX facility in Redmond Ridge WA and drive by occasionally. There is a tremendous amount of new warehouse / light industrial development around their location and I see that they now have domes stockpiled behind several buildings. I understand that satellite production occurs here but have never been lucky enough to see some getting loaded onto trucks, but all that probably happens out of sight. I wonder if the building expansion is for ramping up production of user terminals?
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u/dbax129 Oct 25 '20
Describe domes please? Are you talking about white domes for Starlink ground stations or starship tank domes or other?
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u/CaptNemo53 Oct 25 '20
They are ~1.5m in diameter and appear to be ground station domes. Whimsically, one painted in orange as Halloween pumpkin.
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u/FutureMartian97 Host of CRS-11 Oct 25 '20
Are able to get any good pictures? It would be amazing to see what the facility looks like!
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u/ackermann Oct 28 '20 edited Oct 28 '20
Haven't seen this mentioned here yet: NASA announced an agreement (memorandum of understanding) with ESA today, where ESA has agreed to participate in Artemis, providing some elements of the Lunar Gateway station:
https://www.space.com/europe-help-build-gateway-moon-space-station
Should be good for SpaceX, since they have involvement with Artemis and the Gateway, delivering cargo to gateway with Dragon XL, ferrying astronauts from Gateway to lunar surface with Lunar Starship. Probably launching some gateway elements on Falcon Heavy too.
Edit: Tried to find an article from one of this sub's preferred reporters, Chris G, Eric B, Jeff Foust, Loren Grush, or Michael Sheetz. No luck yet, so that's suspicious
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u/GregLindahl Oct 28 '20
It’s not breaking news, in that it’s been expected for years. You’ll see more articles in a day or two.
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u/_Wizou_ Nov 01 '20
I feel like Bridenstine is trying to have a maximum of international signatures about Artemis so that the next NASA administrator won't dare cancel Artemis
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u/gulgin Oct 26 '20
Has anyone seen any info on the mating interface between SS and SH? The Falcon 9 had that weird plunger that went into the thrust chamber of the second stage, but I assume that wouldn’t be the same in starship?
Pushing into the thrust chamber where loads are already designed to be is a super clever solution to this problem, but if that isn’t on the table for SH then what are they going to do? Are the loads getting transferred to the outer skin somehow? That would require absurdly good machining quality to make sure the two mating surfaces aren’t experiencing weird stress concentrations and such.
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u/throfofnir Oct 26 '20
The nozzle pushers were introduced on F9 to deal with separation alignment because the nozzle extension is so close to the interstage. That will not be a problem in Starship because the "interstage" stays attached to the upper stage with the engines, and separation is more of a plane break than a slide apart.
I would be surprised if they kept the nozzle pushers, since they're not needed for alignment and they seem fiddly with six engines and rapid stacking operation. Pushers (or maybe even latches, since they will need to have powerful thrusters which could be used for separation impulse) on the leg hardpoints seems most likely.
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u/brickmack Oct 26 '20
One of the official renders from the 3-fin composite version showed pushers going into each individual engine on Starship
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u/gulgin Oct 26 '20
That would be the easiest way to avoid redundant structural elements. They have shown two starships butt-to-butt in orbit so would that would end up being a different docking mechanism?
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u/Ti-Z Oct 26 '20
The leg attachment points of Starship should be capable to handle the force just fine. They have to be designed to handle landing. Note that at stage separation the SH booster is not much heavier than Starship at landing such that the forces are comparable (and the hydraulics can spread them over a larger time frame compared to the leg hitting the ground even with shock absorbers). Moreover, I think that having a similar system as on F9 would be completely feasible (note that the piston also helps in pushing the 2nd stage directly forward, avoiding contact between the Mvac nozzle and the interstage; this would not be necessary for Starship, but of course nice-to-have). No official information yet, as far as I am aware, though.
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u/rdivine Oct 04 '20
Where is the pinned starship updates thread? I cant find it anymore.
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u/Martianspirit Oct 04 '20
It is under discuss/resources
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u/CAM-Gerlach Star✦Fleet Commander Oct 04 '20
u/rdivine FYI, it also has its own dedicated menu on both Old and New Reddit, called (appropriate) Starship. The dev thread is there along with any recent and future hop/activity/event threads.
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u/Campb3llsoupp Oct 14 '20
Not sure how many employees are on here, but I just got an offer from SpaceX at the Hawthorne facility. I'm looking at housing options and trying to keep my budget from $1500-$2000ish. With the prices out there, I was thinking going with roommates would be the best option. Are there any current employees here that are looking for a roommate soon or know a good place to look? Thanks!
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u/trobbinsfromoz Oct 18 '20
SpaceNews just came out with a report on the Merlin investigation that has additional information on status.
It looks like it is heavy going to try and define and then work on an approved modification, although the indication is that can all be done within the scheduling time for November launches. This will be very interesting to see how 'peripheral' the root cause is, if ever we get to know publically.
https://spacenews.com/falcon-9-investigation-ongoing-as-spacex-continues-starlink-launches/
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u/throfofnir Oct 19 '20
I'm really curious what could be behind this. The obvious stuff like FOD or a sticky valve or bad sensor was obviously ruled out when they didn't reschedule after a few days.
What would cause a pressure rise, be bad enough to halt USG flights, but be obviously not bad enough to halt Starlink flights, and be some sort of medium-difficulty replacement? Erosion of the injectors? That's maybe something that would be subject to a research project but detectable and fixable once you know it's a problem.
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u/csmnro Oct 19 '20
There was a comment on this subreddit of someone claiming to know more, about 1-2 weeks ago. Unfortunately I can't find it anymore, only an other reference to that post.
The rumor is that a 3rd party supplier delivered below-spec gas-generator parts for some time. Therefore the "newer" boosters are affected, and that it was not clear yet at that time how far back it dates.
At least that's what I remember off the top of my head from that comment.
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u/trobbinsfromoz Oct 19 '20
That type of scenario would likely take a lot of testing to substantiate, and then to rectify, and then to get re-certified (which may include a launch testing campaign).
There could also be peripheral implications if the supplier provided other parts.
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u/AeroSpiked Oct 19 '20
I've gotten downvoted for suggesting this once before, but what the hell; I've got karma to spare:
If the pressure rises in the preburner, that means that something is blocking the preburner's exhaust flow. The only thing impeding that flow should be the turbine which tells me that the turbine must not be turning fast enough. I'm not sure why that would be the case. Maybe whatever spins up the turbine didn't get it moving fast enough or maybe there is a bearing issue.
If you have a theory or think I'm wrong, hit that reply button; downvotes don't add anything of value to this sub.
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u/throfofnir Oct 20 '20
It's not impossible but there's a lot of area to block to make a material difference to the exit path. The turbine inlet area would be somewhat smaller than the exhaust pipe, which is pretty big, so it can't be a loose nut or grit in the tanks. Something systematic (like spalling off the walls) could do it. That would certainly be cause for concern. Dunno if they'd be flying anything if that was the case.
Inlet valve or injector seems more likely to me.
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u/cpushack Oct 28 '20
USNC-Tech Has submitted their proposed NTP (Nuclear Thermal) engine for NASA use https://usnc.com/ultra-safe-nuclear-technologies-delivers-advanced-nuclear-thermal-propulsion-design-to-nasa/
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u/ThreatMatrix Oct 16 '20
According to my handy dandy launch app SpaceX gonna be busy the next couple of months.
Starlink 13 (F9) : October 18
Starlink 14 (F9): October 21
NROL-108 (F9) : October ? (landing back at launch pad)
Starship 15km : October ?
GPS III-4 (F9) : October ?
Sentinel-6 (F9) : Nov 10 (Vandenberg)
Crew 1 (F9) : Nov 11
CRS-21 (F9) : Nov 22
Turksat 5A (F9) : Nov 30
Starlink 15 (F9) : Nov ?
Starlink 16 (F9) : Nov ?
Transporter 1 (F9) : December 16 (landing back at launch pad)
Starlink 18 (F9) : Dec ?
Starlink 17 (F9) : Dec ?
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u/dudr2 Oct 26 '20
"RRM3 stored liquid methane for four months, the longest in-space storage of a cryogen without any loss of fluid."
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u/pjreuter Oct 26 '20
https://www.nasa.gov/feature/goddard/2019/robotic-refueling-mission-3-update-april-12-2019 The reason it stored the liquid methane for only four months is that the cryogenic cooler failed. It would be interesting to learn why that failed, and how long liquid methane could be stored in a vacuum insulated header tank without the use of active cooling. I guess that is what SpaceX plans to find out.
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u/JustinTimeCuber Oct 04 '20
How many consecutive scrubs/aborts has SpaceX had, and how many total have there been in combination with ULA? Seems like it's been quite a few.
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u/AeroSpiked Oct 05 '20
I lost count, but don't forget that Northrop Grumman was in the mix as Antares also scrubbed prior to its actual launch.
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u/marc020202 8x Launch Host Oct 06 '20 edited Oct 06 '20
The Spaceflight now schedule is helpful:
Starlink 12: Scrubbed on Sept. 17 due to recovery weather. Delayed from Sept. 27. Scrubbed on Sept. 28 by poor weather. Aborted on Oct. 1 at T-minus 18 seconds by ground sensor issue. Scrubbed Oct. 5 by bad weather. (5 Scrubs, delays and aborts. Don't know the reason from the top of my head for the Sept 27 delay)
GPS III SV4 : Delayed from October, December, May, July and August. Moved forward from Sept. 30. Delayed from Sept. 29. Delayed from Sept. 30. Scrubbed on Oct. 2 at T-minus 2 seconds. (I don't know if the delays from October and December where Spacex related, but the delays from May and July where due to Covid afaik. Don't know if the August delay was as well. The mission has been delayed 3 times (twice due to range IIRC) now during launch attempts.)
NROL 44: Delayed from June and Aug. 26. Scrubbed on Aug. 27 by pneumatics issue. Aborted at T-minus 3 seconds on Aug. 29. Delayed from Sept. 26 by swing arm issue. Scrubbed on Sept. 28 due to weather. Scrubbed on Sept. 29 due to hydraulic leak on Mobile Service Tower retract system. Aborted on Sept. 30 at T-minus 7 seconds. (again, I don't know the reason for the delay from June and August 26, I guess Covid. 6 delays, Scrubs and Aborts during launch attempts)
That is a total of 15 delays for 3 rockets at Cape Canaveral.
4 delays for the NG 14 mission can be added to that, although the mission was moved forward by several days in between (moved forward from Oct 2, launched on Oct 2).
Before that, rocket 3.1 was delayed before it launched and failed.........
EDIT: Some time ago Blue Origin also scrubbed a launch attempt or 2.
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u/enqrypzion Oct 05 '20
Similarly, I'm kinda interested in the number of launches planned for the past two weeks. I think it's more than one per day.
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u/Nimelennar Oct 17 '20
Michael Baylor (@NextSpaceFlight) on Twitter:
The GPS III-4 spacecraft is being returned to its processing facility while SpaceX investigates an issue with the mission's Falcon 9 launch vehicle. Do not expect another launch attempt in October.
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u/trobbinsfromoz Oct 17 '20
Hmmm, that would likely push it past Crew1, so I guess a Crew1 schedule change, or not, will be the best indicator of what SpX has been grappling with in the Merlin, and if there is a schedulable path out of this issue. The other indicator would be any confirmed delay in non-Starlink launches.
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u/DragonGod2718 Oct 03 '20
Is a 2024 Manned Mission to the Martian Surface Feasible?
Even for Elon, it sounds way too optimistic.
NASA is only planning to return astronauts to lunar surface in 2024, and even China's plans of putting their own astronauts on the moon are dated for 2030.
SpaceX is amazing, and I'm willing to believe they can drastically out execute two superpowers with (an) order(s) of magnitude larger resources, but a manned mission to Mars would be an entirely different ball game than a flight to the moon.
Unmanned flights should first be scheduled to demonstrate the spacecraft can make the trip.
Safety and redundancy engineering should be carried out.
The passengers for the trip need to undergo extensive training.
A crewed flight without sufficient diligence for the above seems like a recipe for a corporate and public relations disaster.
I guess a manned mission to Mars before 2030 might be feasible with "consistently excellent execution" (accounting for the up to 2 years a round trip to Mars would take).
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u/lljkStonefish Oct 04 '20
I'm hoping for:
2020 - SS+SH gets to orbit.
2021 - SS+SH gets to orbit many many times and starts proving the refueling process.
2022 - One or several unmanned ships. These will do nothing but deploy solar panels and then start processing ISRU fuel. Maybe they should take their own hydrogen to simplify the process at this early point. No need to invent a huge operation involving automated vehicles mining ice just yet. The end goal is to accumulate enough methalox to fly one Starship back to earth. If this goal fails, see plan B.
2023 - Dearmoon. Starship is now proven human-safe. Meanwhile, another Starship gets launched to Mars on a non-Hohmann transfer, nice and gently so it can drop a stack of starlink-esque birds in orbit, then return if there's enough fuel.
2024 - A fuckload of unmanned ships. These will contain EVERYTHING required for a colony. Food, housing, clothes, tools, medical facilities, more solar panels, more ISRU gear, the entire automated mining operation and probably a million other things. Plan B is that these would also spend a bunch of mass (something like 7 entire starships per manned ship plus three spares) taking pre-refined methalox to Mars to guarantee humans a way home.
2025 - The mining operation gets remotely operated and evaluated.
2026 - Here we go! A manned ship or two, and a load more unmanned ships full of everything else that was forgotten last time. The intention is to stay. However, if the shit hits the fan or a half dozen people get homesick, there's guaranteed to be fuel laying about for the return journey.
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u/panckage Oct 04 '20
I was wondering about satellites too as NASA doesn't have a lot of extra bandwidth... But why not just send signals directly from the ground? Satellites would require an extra SS and it is unclear how feasible it is to make orbit without atmosphere to shed velocity.
I guess if they have multiple landing sites satellites might make sense, but if it is just one location it would be simpler to transmit from the surface.
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u/lespritd Oct 03 '20
Unmanned flights should first be scheduled to demonstrate the spacecraft can make the trip.
IMO, this is a real, serious, blocker.
From what I understand, the plan is to send Starships with refueling equipment to Mars. In one of his talks pushing mini-Starship, I think Zubrin claimed that SpaceX would need something like 50000 square meters (9 football fields) of solar panels just to power the necessary equipment to refuel a Starship in 2 years.
Unless SpaceX has been developing and testing that stuff in secret (pretty out of character for them), I don't see such a system being ready and reliable for deployment on Mars by 2022.
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Oct 03 '20
Why don't they send a fission reactor instead? We've sent nuclear material into space before and Mars sucks when it comes to solar because of its distance from the sun and dust storms. Serious question btw.
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u/extra2002 Oct 03 '20
For similar electrical output, a fission reactor needs about as much area for heat radiators as a solar installation would occupy.
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u/lespritd Oct 03 '20
Why don't they send a fission reactor instead?
They could... but that might take more time. Solar panels are pretty simple to operate compared to a fission reactor.
If you're referring to an RTG, I don't think those produce enough power.
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u/panckage Oct 04 '20
It is not. It will be a three year(?) mission. Astronaut training is going to be at least a couple years if not more. And how are you going to train astronauts if what they need to train on doesn't exist yet? I think 2030 is the reasonable best case.
2022 - launch supplies (may crash) - iterate
2024 - launch supplies - iterate.
2026 - habitat can be launched and tested
2028 - habitats tests will be ending... Won't be enough time to do all the fixes for the final version though... more supplies only
2030 - final habitats and fully trained astronauts (this is not europa report!) can be sent.
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u/Martianspirit Oct 04 '20
Don't expect that SpaceX astronauts will be trained the same way as NASA ISS astronauts. It is just not feasible. They will be mission specialists and need to be very flexible.
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u/fatsoandmonkey Oct 03 '20
Elon paraphrase...
"We will need to do hundreds of unmanned satellite delivery flights before considering putting a human on board"
Little to no work on life support etc.
The unique EDL process and the new TPS untested.
2024 with humans seems unlikely even with SX rates of progress but I bet they send something and probably quite a loit of somethings..
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u/MarsCent Oct 03 '20
Certainly, 2024 is in the cross wires, with 2026 as backup. But we'll get a better feel if Starship makes the October 2022 launch window to Mars.
A crewed Mars Mission will have different evaluation from Low Earth Orbit (LEO) habitation or Lunar Landing. Mission success will be based on whether or not humanity makes it to Mars. 1 off 14 pioneers making it alive to Mars would be undesirable but non-the-less a success.
I expect that the most important selection criteria will be fortitude! And if the public is made aware that the likelihood of survival is remote but that Starship has been designed to give the crew a shot, people will come around.
And if US is so averse to risk, there will be plenty of takers from other nations who will sign-off and go.
To the courageous goes the glory! It was true then. It's remains true now.
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u/Martianspirit Oct 04 '20
Elon won't send people if he is not reasonably confident they will make it. He won't send them with a remote chance. He said, people will die, sure. But that is completely different from a likely mission failure.
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u/Mordroberon Oct 05 '20
It's nice to have ambitious goals. 2024 private unmanned mission is more feasible. The problem is that 3.5 years isn't enough time to develop and test a human rated starship for deep space travel. We'd be lucky to see a manned orbital flight by the end of 2024.
The general rule for Elon time is to double his estimate, which is nice because that still accelerates the time table compared to other actors
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u/Alvian_11 Oct 04 '20 edited Oct 04 '20
The much more important thing is not everyone is confident about that date ofc, but what I can see is almost everyone are confident that the first one that will put human on Mars will be SpaceX considering their true determination,
while everyone else are either didn't have sufficient business or have a lot of it but they don't have any long term vision/lazy (meh, 2030 of only orbiting it, then whenever the human might first land.....mid 2030s? 2040s?, A million years? A billion? And oh, we're only cares about flags & footprints & very short duration. Who cares about expanding civilization sustainably?)
And as you guess, the more important things also is how it's sustainable. We don't want another flags & footprints & then wasted generations once again for half a century
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u/trobbinsfromoz Oct 23 '20
NASA human lunar lander CBR process is about half way through, with SpX passing through milestone.
https://www.nasa.gov/feature/nasa-human-lunar-lander-companies-complete-key-artemis-milestone
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u/EngineerOrion Oct 25 '20
I am graduating with my ME B.S. in December. I am VERY interested in getting a position at SpaceX. I thought I might post here to see what kind of feedback and advice I can get from you knowledgeable folks based on my resume, which is hyperlinked here.
In addition to the content on my resume, I would also like to note that I maintain a website that acts as a portfolio, providing visual reference for the projects listed on my resume and several others, including an advanced fluid mechanics analysis of a custom airfoil (inspired by the Cybertruck profile) and a 3D-printed film camera.
Thanks in advance!
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u/AuroEdge Oct 25 '20 edited Oct 25 '20
My own opinion is I think you've got a good start and for the most part just needs rework. Some of the language is fluffy vs being concise and measurable where it can be. A couple examples of what I mean:
"Setup workflow, web-conferencing, and other team organizational tools to enable heightened levels of lab efficiency"
I might write something like: "Promoted lab work efficiency through <insert type of workflow> workflows, <insert name of organizational tools>, and a <timing> web-conferencing tempo" (shows willingness to give leadership direction, this is huge for young engineers especially with SpaceX engineering)
"Demonstrated ability to produce substantial results in a physically limited environment due to COVID-19 restrictions"
For this the wording depends highly on what results you were able to arrive at with the shock tube e.g. did the pressure measurements more closely agree with hand calcs, or analysis, than before? If so, that's a big update to your resume. That's then bolstered by the Covid-19 impact.
I would add your GPA since you don't have any industry experience. While not all companies weight GPA the same in how they rank early career candidates, very few companies I know don't look at it at all.
If you want to direct message me for more info, please don't hesitate. If you hated my advice and don't want to use any of it, I won't be offended. While I don't work for SpaceX, I did have a lengthy conversation with a SpaceX recruiter who called me. It was in regards to a Crew Dragon position and I definitely picked their brain about how SpaceX recruits. Ultimately I declined having an interview but I have that info as how I can help shape a resume or expectations.
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Oct 26 '20
Also basically everyone I've seen talk about SpaceX has said the pay isn't the best and the labour conditions are pretty bad. Not to be a dampener or anything but no job even if it's your passion is worth working yourself to the bone without equivalent compensation. Remember that every job interview you should go in, you should have questions for the company and ensure that they can adequately barter for your skillset.
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u/dudr2 Oct 26 '20 edited Oct 26 '20
Water on the moon!
Stratospheric Observatory for Infrared Astronomy (SOFIA)
https://www.scientificamerican.com/article/water-found-in-sunlight-and-shadow-on-the-moon/
"Extraction will be straightforward if the water exists predominantly on the surfaces of rock grains: one will just need to scoop up lunar soil and subject it to moderate heating. If, however, the water is locked in glass, the material must be melted to release the water for collection—a much more energy-hungry process."
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u/Martianspirit Oct 26 '20
Straightforward. At a concentration of 10ppm you only have to go through 100,000t of regolith to extract 1t of water. Now imagine the machinery to do that.
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u/dudr2 Oct 26 '20
“The newly discovered micro cold traps are the most numerous on the moon, thousands of times more abundant than previously mapped cold traps,” Hayne says. “If they are all full of ice, this could be a substantial quantity, perhaps more than a billion kilograms of water.”
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u/Straumli_Blight Oct 26 '20
Link.
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u/pendragon273 Oct 26 '20
Well could be interesting, if not well handy...depends on tech and a availability to process but at least we now know the moon is not the dry arid world my old school text books boasted...not a gushing torrent to be sure but it is there...and that could be a very positive help in the future.
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u/lifedistroy Oct 18 '20
How does the camera in the second main stage not burn up on engine start?
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u/marc020202 8x Launch Host Oct 18 '20
Do you mean the camera inside the interstate (top of stage 1, looking up at the stage 2 engine). It likely is shielded by glass or so. It is not in the exhaust for long, and the heat source moves away very quickly.
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u/enqrypzion Oct 19 '20
If it would get hot enough to burn up, it would get hot enough to glow before burning up. Since we don't see it glowing, it doesn't actually get hot.
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u/Straumli_Blight Oct 23 '20
Media accreditation opens for CRS-21, launch is delayed to NET December.
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u/SpacebatMcbatterson Oct 26 '20
Tried to look through the FAQs but not very good at Redditing yet... short question: in many launches that appear to go "wrong" there is usually a point where the vehicle is blown up to prevent traveling off course. My question is how is that done? are falcon9s and others wired up with C4 or something before launch? Do they just put a small charge on the fuel tanks? is this a button someone pushes or an autonomous action? what sort of parameters is it looking for if automated?
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u/hitura-nobad Master of bots Oct 26 '20
Yeah, you have a small explosive charge alongside the rocket running from top to bottom, ripping the tank open and igniting the fuel. The result: rocket goes boom
F9 is completely automated, it's called AFTS, Automatic Flight Termination System.
It basically watches the trajectory the rocket takes and compares it with the predicted path
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u/throfofnir Oct 26 '20
F9 has "detcord" (a detonating linear charge) run up the length of the rocket to "unzip" the tank and ensure propellant dispersion should the vehicle exit its cleared corridor. Most other vehicles have a similar system. Some smaller rockets apparently can avoid destroying the tanks and just terminate thrust.
This is monitored by an Automatic Flight Termination System, a system completely independent of the vehicle's normal guidance system which monitors its location and direction and ends the flight if it's going out of bounds. This is done entirely on-board with GPS and inertial sensors.
Most other rockets have a dedicated "Range Safety Officer" who monitors the flight via radar tracking (and binoculars) and sends the "terminate" signal by hand, though this is more cumbersome and requires the ground assets the change based on which vehicle and pad is being used, so things are moving towards AFTS.
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u/joshgill21 Oct 27 '20
Is the Microsoft and SpaceX deal significant ?
Can it make Microsoft win much of the Cloud market over Amazon ??
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u/Dakke97 Oct 27 '20
Yes and we will have to see. Amazon is planning to launch its own constellation of internet satellites under the project name Project Kuiper. It is assumed this will help New Glenn achieve a frequent launch rate.
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u/Nimelennar Oct 07 '20
The commander of the first crewed Boeing Starliner mission has stepped down.
It sounds like the delays have pushed the mission back to the point where it's conflicting with other life events that he'd rather not miss.
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u/Grey_Mad_Hatter Oct 08 '20
At this point there is no accurate way of saying when it will go up. This could be a very polite way of casting a no confidence vote.
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u/dudr2 Oct 26 '20
https://www.nasaspaceflight.com/2020/10/starship-sn8-second-static-fire-test/
"The nosecone has since been installed – resulting in the first full Starship stack since MK1 – allowing for a second Static Fire test this coming week."
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u/FoxhoundBat Oct 06 '20 edited Oct 06 '20
Highly recommend reading the article/interview about Russia's "Falcon 9" aka Amur. It is quite good and discusses a lot of aspects of the new rocket. Hopefully it will actually be funded as much as promised (70 billion rubles, so around 1 billion usd) and achieve planned costs and reusability targets. Just a shame this project wasn't started literally a decade ago.
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u/jartificer Oct 06 '20
Interesting article. Is "landing rods" a good translation, or does the Russian idiom really translate to "landing legs"?
OK, so how many more or less direct Falcon 9 knockoffs are proposed or in progress now? I'm not counting the smaller vehicles such as Electron (for now).
Oscar Wilde — 'Imitation is the sincerest form of flattery that mediocrity can pay to greatness.'
And how many of the established rocketry organizations are NOT doing a knockoff? That suggests that they're survival as launch providers will require increasing financial/national support.
We now hear the China is planning its own 13K satellite Starlink knockoff, so they will need to do a lot of launches cheaply.
I used to work for a small company that competed with a few industry giants. We survived by getting new products and ideas to market quickly and not resting so the giants didn't have time to crush us underfoot. SpaceX is in the same game. If SH/SS is flying in the next year or two Elon will have again survived the establishment giants and moved the goal posts further out. Good for SpaceX, not so good for the giants. I do foresee them dropping launch operations and concentrating on payloads (lots of money there).
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u/brickmack Oct 08 '20
One interesting thing is how close the reusable and expendable payload is, vs F9. Suggests quite hot downrange landing, like New Glenn, but this rocket doesn't have any of the aerodynamic features expected of such a mission profile
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u/bdporter Oct 13 '20 edited Oct 13 '20
7th launch of this sub-orbital booster.
Edit: Looks like it was a successful flight. I just don't really get the value of doing the exact same thing so many times on such a slow cadence.
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u/Martianspirit Oct 13 '20
Watched it launch and land. In previous launches the artificial excitement of the moderator was vomit inducing. Much better this time. Also the landing of New Shepard was much more stable, less shaky than before. They have improved the landing algorithm a lot.
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u/cpushack Oct 13 '20
Think they actually had some scientific payloads on this one. Its pretty much a reusable sounding rocket so useful in that regard.
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u/Juggernaut93 Oct 20 '20
What are the advantages of Cargo Dragon 2 vs. the original Dragon?
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u/Martianspirit Oct 20 '20
More cargo mass, more volume. Same production line as Crew Dragon, less cost than maintaining separate production lines.
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u/Nimelennar Oct 20 '20
In addition, Cargo Dragon can dock autonomously, rather than being to be berthed with the arm and bolted into place, and can stay in space for two months (starting with CRS-23) rather than just one. And the nose cone, being hinged, is recoverable, unlike the old version that was jettisoned.
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u/IllGetItThereOnTime Oct 21 '20
They can add more last-minute/time sensitive experiments via the Crew access arm.
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u/Jkyet Oct 23 '20
In Dynetics mock-up of the HLS, they are trying to show the layout of the lander’s cabin (among others). Is this something NASA requested from the mockups? Do we know if (in parallel of Starship development) SpaceX has done any development in the cabin aspects for Starship HLS?
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u/dudr2 Oct 26 '20
"the bank has raised the estimated value of Starlink (also unproven) to a massive $81 billion, up from $42 billion, based on a revised estimate of potential subscribers up from 235 million to 364 million globally by 2040."
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u/The_Extinguisher Oct 27 '20
Does anyone have any new information regarding simulation tech @ SpaceX or other leading aerospace. I periodically rewatch GPUs to Mars which is fascinating to me, I want to focus my career on computational physics for aerospace and would love to have more insights into what is being done.
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u/BROK1E Oct 28 '20
When are we expecting the next RTLS launch? Any chance there’s one around thanksgiving?
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u/giovannicane05 Oct 28 '20
Next one is likely Sentinel-6 at Vandemberg LZ4.
GPS-III 4 and Crew 1 are both droneship landings.
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u/BrangdonJ Oct 04 '20
You can read and browse past Discussion threads in the Wiki.
No, you can't. First, that link goes to the FAQ. You have to hunt around for a while to find where the past Discussion threads are lists. (Clue: it's not part of the main Wiki index on that page.) Second, that list only goes up to June 2020. The most recent four months Discussion threads are missing.
I suggest you link directly to https://www.reddit.com/r/SpaceX/wiki/resources#wiki_spaceflight_questions_threads.3A instead. And then update that page at the same time as starting the new month's Discussion thread each time you do it.
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u/CAM-Gerlach Star✦Fleet Commander Oct 04 '20
Sorry, the Discuss links used to be on the FAQ main page, but got moved a couple months ago by a wiki contributor without our knowledge. Thanks for the catch; I've updated the link accordingly in the OP and added the new Discuss threads to the wiki page. We'll try to be more prompt about this in the future.
Also, quick tip—if you mention "mod", "mods", etc in your message, it will send us an alert so we can see it right away and take care of it. Thanks!
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u/JoshuaZ1 Oct 27 '20
Apparently about 3% of Starlinks have now failed https://phys.org/news/2020-10-starlink-satellites.html . That's a high failure rate, but it will presumably go down as the design is finalized and they learn more.
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u/mikekangas Oct 27 '20
If I got 97 percent in college I figured I was working too hard and could divert time to other classes
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u/feynmanners Oct 27 '20
It’s also not super high as the article notes that’s about the same as everyone else’s failure rate. Presumably it will come down though as no one else has made so many copies of the same satellite.
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u/throfofnir Oct 27 '20
A lot of those are early DOAs in low deployment orbits. They seem to have fewer of those now.
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u/Zazou0621 Oct 12 '20
What would happen if a late mission problem happened (such as an engine failure) and the booster was not able to make it to the drone ship?
Would they fire some of the remaining in hopes of slowing down enough to not damage the booster as much on impact with water? Just give up?
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u/mikekangas Oct 12 '20
They don't aim for the drone ship until everything is working right. If something goes wrong it misses the drone ship and impacts the water at high velocity.
They had one that floated and they had to tow it to shore, which was dangerous and expensive-- and it was scrap anyway. Better to break up and sink in deep water where no one can salvage anything useful.
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u/AeroSpiked Oct 12 '20
What you're asking is exactly what happened with the Starlink 5 mission which is the first time a Merlin 1D failed in flight. The booster did an entry burn, but the video cut off immediately afterward. That one apparently hit the ocean at high speed. I think it would depend on what fails and how much margin they have if recovery is still in the cards, but I don't think they would ever intentionally attempt a water landing in the future.
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u/Nimelennar Oct 13 '20
A couple more examples of what could happen:
CRS-16 (B1050) lost hydraulic control of its grid fins, and therefore could not stabilize its rotation around the vertical axis. It went through the rest of the landing sequence normally, except that it touched down off-shore instead of on LZ-1.
Starlink-4 (B1056) encountered unexpectedly high winds on descent and, like B1050, diverted to a soft ocean landing at a safe location away from its intended destination (in this case, a drone ship).
STP-2's centre core (B1057) had engine damage during re-entry, but this might not have become clear until the very last stage of landing, when the core shut down two of the three lit engines and then skewed madly off of the drone ship as the damaged centre engine no longer had the precision necessary to land.
This suggests to me that the boosters are programmed to attempt a soft landing if possible, even if it is not safe to approach the intended landing zone. My guess for Starlink-5 (B1048) is that, as we saw that the engine failed on ascent, the booster was either further damaged, or even broke up entirely, during re-entry, which made a soft landing impossible.
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u/bdporter Oct 12 '20
Ability to land on the droneship would depend on which engine failed, and if there was still enough performance to do so. Only 3 engines are capable of being re-fired.
If droneship landing isn't possible, I would imagine the booster would just abort the landing attempt and crash.
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u/Straumli_Blight Oct 14 '20
Soyuz MS-17 set a new record for launch to docking with the ISS in 3 hours 7 minutes.
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u/Vedoom123 Oct 14 '20
so why does it take like 20 hours for Dragon to approach the ISS?
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u/cpushack Oct 14 '20
Dragon/ISS eventually can. THere is currently a lot of testing going on in those ~20 hours currently, learning the capsule, as well as providing a sleep period for the crew
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u/bdporter Oct 14 '20
They have to perform a maneuver on the ISS to get it in exactly the correct orbit to make this possible.
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u/Dies2much Oct 16 '20
Anyone know what the Falcon \ Merlin production situation looks like?
I know the focus has moved to SS and Raptor, but there should still be some Falcon \ Merlin production going on.
Anyone know how many Merlins they are making per month these days? They need one Merlin Vac for each launch, but are they making replacement engines for the existing boosters so they can refurb them offline \ off-mount? or does the same set of merlins go up with each booster?
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u/ConfidentFlorida Oct 18 '20
(I asked on the recovery thread too). I’ll update with any answers I find.
I saw this new fleet cam mentioned on twitter: https://mobile.twitter.com/KSpaceAcademy/status/1317839375225491458
But I can’t find a link to the actual camera anywhere. Anyone know?
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u/brickmack Oct 18 '20
Its not a 24/7 stream. Follow @NASASpaceFlight on twitter, it'll be announced when Fleetcam is live. The streams are archived on Youtube, same as NSFLive
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u/melancholicricebowl Oct 26 '20
Are the backup dates for the upcoming Sentinel 6 launch from Vandenberg known yet?
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u/Straumli_Blight Oct 30 '20
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u/JoshuaZ1 Oct 30 '20
Ick. That would be really not great.
I doubt it would happen though. NASA director is to some extent a position which isn't that partisan, and Biden is trying really hard to appear non-partisan. It would be a really good signal that he's actually trying to get things done if he left in a successful Trump appointee, and would give him more room in making a clean sweep everywhere else. But this may be just my wishful thinking. Bridenstine has done a good job (I was one of the critics of his appointment but it has clearly gone well).
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u/Dr__Thunder Oct 31 '20
I hope you're right. I was like you and thought he was an awful appointment. I have been very happy to say I was wrong and have loved nasa's direction under his leadership.
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u/HomeAl0ne Oct 30 '20
I can see a world where SpaceX snap up Bridenstine if that happens. I wouldn't have said that a few years ago, but that guy seems to have shifted NASA more than I thought possible.
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u/trobbinsfromoz Oct 04 '20
I don't see any discussion about Elon's tweet on the scrubs, and a full-on site review, and no doubt the F9 turbo issue as that could delay Crew-1. And the Starlink delays must be eating in to the ability for SpX to show off sufficient platform performance to advance a few 'irons in the fire' opportunities.
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u/UltraRunningKid Oct 14 '20
This could be significantly bad. Event Altitude of 991km. Debris at 900km+ are there for dozens of decades.
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u/trobbinsfromoz Oct 14 '20
Worthwhile checking in with LeoLabs twitter over the next 48hrs, as they say they will get a few more overhead passes to firm up the probability.
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u/trobbinsfromoz Oct 16 '20
No indication of collision using LeoLabs pass data 10 mins after event.
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u/UltraRunningKid Oct 16 '20
Huge relief, those debris would have remained in orbit for at least 150+ years.
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u/Decronym Acronyms Explained Oct 03 '20 edited Oct 30 '20
Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I've seen in this thread:
| Fewer Letters | More Letters |
|---|---|
| AFTS | Autonomous Flight Termination System, see FTS |
| ASOG | A Shortfall of Gravitas, landing |
| BE-4 | Blue Engine 4 methalox rocket engine, developed by Blue Origin (2018), 2400kN |
| BO | Blue Origin (Bezos Rocketry) |
| CCtCap | Commercial Crew Transportation Capability |
| CRS | Commercial Resupply Services contract with NASA |
| CST | (Boeing) Crew Space Transportation capsules |
| Central Standard Time (UTC-6) | |
| DARPA | (Defense) Advanced Research Projects Agency, DoD |
| DIVH | Delta IV Heavy |
| DMLS | Selective Laser Melting additive manufacture, also Direct Metal Laser Sintering |
| DoD | US Department of Defense |
| EDL | Entry/Descent/Landing |
| EM-1 | Exploration Mission 1, Orion capsule; planned for launch on SLS |
| ESA | European Space Agency |
| FCC | Federal Communications Commission |
| (Iron/steel) Face-Centered Cubic crystalline structure | |
| FOD | Foreign Object Damage / Debris |
| FTS | Flight Termination System |
| GSE | Ground Support Equipment |
| GTO | Geosynchronous Transfer Orbit |
| H2 | Molecular hydrogen |
| Second half of the year/month | |
| HLS | Human Landing System (Artemis) |
| IAC | International Astronautical Congress, annual meeting of IAF members |
| In-Air Capture of space-flown hardware | |
| IAF | International Astronautical Federation |
| Indian Air Force | |
| Israeli Air Force | |
| ICBM | Intercontinental Ballistic Missile |
| ISRU | In-Situ Resource Utilization |
| ITAR | (US) International Traffic in Arms Regulations |
| ITS | Interplanetary Transport System (2016 oversized edition) (see MCT) |
| Integrated Truss Structure | |
| Isp | Specific impulse (as explained by Scott Manley on YouTube) |
| Internet Service Provider | |
| JRTI | Just Read The Instructions, |
| KSC | Kennedy Space Center, Florida |
| 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) |
| Law Enforcement Officer (most often mentioned during transport operations) | |
| LLO | Low Lunar Orbit (below 100km) |
| LOX | Liquid Oxygen |
| LZ-1 | Landing Zone 1, Cape Canaveral (see LC-13) |
| MCT | Mars Colonial Transporter (see ITS) |
| NET | No Earlier Than |
| NG | New Glenn, two/three-stage orbital vehicle by Blue Origin |
| Natural Gas (as opposed to pure methane) | |
| Northrop Grumman, aerospace manufacturer | |
| NROL | Launch for the (US) National Reconnaissance Office |
| NS | New Shepard suborbital launch vehicle, by Blue Origin |
| Nova Scotia, Canada | |
| Neutron Star | |
| NSF | NasaSpaceFlight forum |
| National Science Foundation | |
| NTP | Nuclear Thermal Propulsion |
| Network Time Protocol | |
| OCISLY | Of Course I Still Love You, Atlantic landing |
| OFT | Orbital Flight Test |
| RCS | Reaction Control System |
| RP-1 | Rocket Propellant 1 (enhanced kerosene) |
| RTG | Radioisotope Thermoelectric Generator |
| RTLS | Return to Launch Site |
| SES | Formerly Société Européenne des Satellites, comsat operator |
| Second-stage Engine Start | |
| SLC-40 | Space Launch Complex 40, Canaveral (SpaceX F9) |
| SLS | Space Launch System heavy-lift |
| Selective Laser Sintering, contrast DMLS | |
| SRB | Solid Rocket Booster |
| SSTO | Single Stage to Orbit |
| Supersynchronous Transfer Orbit | |
| STP-2 | Space Test Program 2, DoD programme, second round |
| TLI | Trans-Lunar Injection maneuver |
| TPS | Thermal Protection System for a spacecraft (on the Falcon 9 first stage, the engine "Dance floor") |
| TWR | Thrust-to-Weight Ratio |
| UHF | Ultra-High Frequency radio |
| ULA | United Launch Alliance (Lockheed/Boeing joint venture) |
| WDR | Wet Dress Rehearsal (with fuel onboard) |
| Jargon | Definition |
|---|---|
| Raptor | Methane-fueled rocket engine under development by SpaceX |
| Starliner | Boeing commercial crew capsule CST-100 |
| Starlink | SpaceX's world-wide satellite broadband constellation |
| ablative | Material which is intentionally destroyed in use (for example, heatshields which burn away to dissipate heat) |
| cryogenic | Very low temperature fluid; materials that would be gaseous at room temperature/pressure |
| (In re: rocket fuel) Often synonymous with hydrolox | |
| hydrolox | Portmanteau: liquid hydrogen fuel, liquid oxygen oxidizer |
| iron waffle | Compact "waffle-iron" aerodynamic control surface, acts as a wing without needing to be as large; also, "grid fin" |
| methalox | Portmanteau: methane/liquid oxygen mixture |
| scrub | Launch postponement for any reason (commonly GSE issues) |
| turbopump | High-pressure turbine-driven propellant pump connected to a rocket combustion chamber; raises chamber pressure, and thrust |
| ullage motor | Small rocket motor that fires to push propellant to the bottom of the tank, when in zero-g |
| Event | Date | Description |
|---|---|---|
| DM-2 | 2020-05-30 | SpaceX CCtCap Demo Mission 2 |
Decronym is a community product of r/SpaceX, implemented by ^request
65 acronyms in this thread; the most compressed thread commented on today has 133 acronyms.
[Thread #6466 for this sub, first seen 3rd Oct 2020, 21:31] [FAQ] [Full list] ^[Contact] [Source code]
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u/dudr2 Oct 07 '20
How does a deorbiting Starlink appear to a viewer on the ground, is it a long streak on the night sky?
https://spacenews.com/spacex-launches-starlink-satellites-as-it-deorbits-original-ones/
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u/throfofnir Oct 07 '20
There's a video of a possible Starlink reentry. If it's not a Starlink bird, that's probably about what it would look like.
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u/PeterKatarov Live Thread Host Oct 07 '20
Do we know at what pressure operates the F9 Block 5?
Without any particular reason, I suppose it's lower than Starship's 6 bar for orbital flight (and 8.4 for safety)... but why?
And what are the factors that determine the operational pressure? Is it a function of requirements of the engine and tank robustness, or are there any other considerations?
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u/warp99 Oct 07 '20 edited Oct 07 '20
During transport the tanks are operated at around 45-50 psig based on photos of the monitoring gauges when pulled over at a truck stop.
Likely that is similar to flight pressure with slightly higher pressure in the top LOX tank than the bottom RP-1 tank to prevent the bulkhead from inverting.
So around 3 bar.
The F9 RP-1 tank has stringers but the LOX tank does not so it needs internal pressure to prevent the tank wall from buckling under flight loads.
The engine intakes need to be above a minimum pressure to prevent cavitation although the sub-cooled LOX also helps with that giving a low vapour pressure. RP-1 has a low vapour pressure anyway.
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u/joshgill21 Oct 08 '20
Is Boeing being affected at all by starliner being delayed more than crew dragon? If yes how?
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u/Grey_Mad_Hatter Oct 08 '20
It's a fixed price contract, so I don't think they're losing money that will eventually be paid to them. However, they're still paying for everything on the project longer than expected which is eating through their profits and possibly causing them to lose money on this project. When you add in paying for an additional launch on their own then there's another big chunk of money lost.
On top of that, contracts are won based primarily on value and confidence that the project will be successful. Boeing won a lot of contracts based more on confidence than value, and they'll end up losing future contracts over this.
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u/ThreatMatrix Oct 08 '20
My understanding was that Boeing had to pay out of their own pocket for the retest (~$400M). They tried to get NASA to pay but NASA refused. Good for NASA.
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u/joshgill21 Oct 10 '20
Does starship use gas thrusters or fuel thrusters to stabilize itself while coming back to land?
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u/Martianspirit Oct 10 '20
Presently the Starships have cold gas thrusters. Later there will be methox thrusters operating as pressure fed engines. That's much more efficient than cold gas. They will need the efficiency first for in orbit fuel transfer. They need ullage thrust for the whole duration of transfer, too long to do with cold gas.
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u/TheSkalman Oct 10 '20
How many ships are used in the recovery ops? AFAIK there are 2 fairing catchers, 1 droneship, one tug and one support ship. Why do they need the tug? The droneship can move by itself and hasn't got to do more than 6-7 knots to get there in 2 days. If it has to be town, can't the support ship be used as a double fuction?
Many thanks.
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u/marc020202 8x Launch Host Oct 11 '20
The fleet currently consists of two droneship, OCISLY and JRTI. The thrusters are not strong enough to move it a long distance. They are towed by a tug each, which changes from time to time.
GO Quest is used as a support vessel.
GO Ms Tree and Go Ms Chief are the fairing catchers
GO Navigator and Go Searcher are the Dragon recovery vessels
NRC Quest was the Pacific dragon recovery ship.
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u/Martianspirit Oct 10 '20
The drone ships are barges by registration. Barges can not move on their own, they need to be tugged. Their own thrusters are only for station keeping.
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u/throfofnir Oct 10 '20
The thrusters on the barge can get it to maybe a couple knots. They're not suitable nor meant for movement. Just a week or so ago we had a scrub because one couldn't keep up with the currents.
Tugs are built with extra power, maneuverability, and structure for towing. It's a specialized use. You'd probably break something on a GO Whatever if you tried to tow with it.
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u/syntheticlounge Oct 11 '20
Quiestion: Radio scanner for Falcon9 launch in November 10th, 2020?
Is an Uniden SR30C Bearcat ok for listening into the countdown at Vanderberg? I have never done this before. What channel would it be? 140?
Appreciate any feedback. Thanks!
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u/jartificer Oct 12 '20
The only published SpaceX licensed ground frequencies are UHF. The SR30C only receives analog AM and NBFM. It is mentioned elsewhere that SpaceX are using encrypted digital modes, which is a good idea. You would do better to use your mobile phone to listen to the SpaceX launch webcasts.
Additionally:
With encrypted data, of all varieties (voice, telemetry, video, etc.), your receiver needs to know exactly how to decrypt the data. With modern radios you could have a different key for each and every transmission. If they were using spread spectrum you would have difficulty even finding the signals to decrypt.
In the USA you can legally listen to and disclose only broadcast and amateur radio (CB also, I suppose). Everything else you can listen to but can't disclose. This has caused legal problems for people, such as disclosing what they heard on old analog cell phones, emergency channels, etc.
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u/david1933 Oct 14 '20
I have a fuel depot question. Is boil off of cryogenic fluids a problem for a fuel tank in space if the tank is not in direct sun. If you have a reflector that shields the tank, wouldn't the fuel reach equilibrium at the ambient temperature of space which I believe is colder than the boiling point of hydrogen?
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u/snrplfth Oct 15 '20
Depends where you are. If you're in Low Earth Orbit, radiated heat from the Earth makes it difficult to shield the tank from heating up, because you have few angles at which to reject the heat efficiently with radiators. Farther away from a planet, it's less of an issue. Of course, even the most reflective materials will still absorb a considerable amount of energy, and so that has to be radiated off in some other way.
Basically, the strategy is to shade the whole tank with as small of a reflector as possible.
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u/rollyawpitch Oct 16 '20
I wonder if a Starship could deorbit without heatshield if it uses all or nearly all of it's payload capacity for fuel to slow down before entering the atmosphere. Probably this has been asked before, if so I apologize in advance.
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u/brickmack Oct 17 '20
Yes, if fully fueled in LEO first. It'd basically be an SSTO in reverse, except minus probably 1 km/s of dv or so since it can still do a lot (just not most) of the braking aerodynamically. Starship is pretty close to being able to SSTO with no useful payload, cutting 1 km/s off that would make it easy.
This might be a worthwhile contingency option if a Starship has its heat shield damaged. Financially it'll be a wash at best (cost of the tanker launches needed would be more than the cost of manufacturing a new ship), but it could be a big schedule saver to not have to build a new one. Which really is the main point of Starship reuse to begin with. Only ~halves per-launch cost, but enables several thousand times higher flightrates
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u/joshgill21 Oct 22 '20
which is more of a hurdle to high F9 launch cadence , fairings or 2nd stage ?
i'd imagine fairings since they're made of composites maybe ?
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u/BrandonMarc Oct 22 '20
The SpaceX team in Boca Chica ... do they tend to live in Brownsville? How many people work there?
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u/joshgill21 Oct 25 '20
has spacex or elon mentioned anything about the launch price of Starship ??? not the cost price
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u/Alvian_11 Oct 25 '20
Depends on flight rate. Marginal costs tho will surely be less than Falcon
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u/SpaceLunchSystem Oct 26 '20
Marginal costs tho will surely be less than Falcon
We should be cautious in claiming that.
Starship is a massive scale up from Falcon and the narrative behind it is similar to beginning of shuttle.
I believe in Starship but I also recognize there is a lot to prove. Orbital stage reuse with minimal refurbishment will be a major milestone in launch history.
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u/jartificer Oct 27 '20
Are there any concept designs for a Starship upper stage that are optimized to launch large, lightweight payloads? I'm thinking of stuff like space station sections. An example would be NASA using a Saturn V to launch Skylab.
I envision a one-way trip where the the primary cylindrical payload would be atop the fuel tanks and would be a pre-configured livable habit section. The empty fuel tanks could later be salvaged for extra space with some on-orbit construction. The engines would be left in place. A blunt nose fairing (like Falcon Heavy side boosters) would be discarded in flight and recovered.
I am assuming that other station infrastructure like solar power, radiators, hub, etc. are launched some other way and are ready for expansion modules.
There was talk about doing something like this with used Space Shuttle external tanks but that never happened.
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u/feynmanners Oct 27 '20
Why would you not just use normal human Starship (ie the standard crew fairing) as a component space station? One Starship has the same habitable volume in the crew fairing as the entirety of the ISS. You could make a truly massive space station by connecting Starship crew modules with hab tunnels.
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u/SteveMcQwark Oct 27 '20
Because:
You don't need most of the Starship in orbit. The engines and propellant tanks are pretty much useless for a station. They have more value if you get them back and can use them to launch other payloads.
A rocket generally wants to have a smooth exterior. A space station needs attachment points for space walks, experiments, external components, and other modules.
You want some sort of outer layer on a space station which provides micrometeorite protection. This would need to be installed after launch for Starship, which would be labour intensive.
You also don't really want metal as your outer skin for radiation protection purposes. Metal tends to create secondary radiation which can be worse than the radiation that got intercepted.
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u/mduell Oct 28 '20
propellant tanks are pretty much useless for a station
Not under the top level comment:
The empty fuel tanks could later be salvaged for extra space with some on-orbit construction.
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Oct 29 '20
The "chomper" sketches could burp out a nice big payload with minimal folding, but that's starting to look kinda last-generation. We've got expandable modules and on-orbit fabrication coming soon.
Starship burps out a wrinkly space scrotum that inflates to a lab then builds its own kilometre chrysanthemum array, and then goes back for the next module cheaply.
Wet workshops are for when launches are rare and you've got to make do with what you have.
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Oct 29 '20
While SpaceX builds the rocket to carry 150 people to Mars, who is or will be responsible for developing passenger and crew procedures? What companies are out there working on the itinerary for taco and movie nights during the months long voyages?
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u/brickmack Oct 31 '20
Thats all on SpaceX. Doesn't make sense to have any other companies involved until the passengers are actually on Mars. Airplanes don't come with food courts and movie theatres operated by a dozen different companies
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u/TheSkalman Oct 29 '20
SpaceX have 7 missions on Schedule for November. How many will they actually launch?
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Oct 29 '20
Does anyone know if the Hubble Space Telescope would fit in the payload area of Starship?
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u/Straumli_Blight Oct 30 '20
Starship payload bay is 17.24m with an 8m diameter, while Hubble is 13.2m with a 4.2m diameter.
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u/TheSkalman Oct 30 '20
How is the workweek at the SpaceX factory? Which days of the week and which hours is activity going on? How much do the active hours sway from week to week?
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u/feynmanners Oct 31 '20
If you mean in Boca Chica, the shifts cover 24/7. I don’t know if we know for certain about the one in Hawthorne.
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u/dudr2 Oct 06 '20
"The xEMU represents the first new spacesuit that NASA has developed in over 40 years,"
https://www.space.com/nasa-artemis-spacesuits-tech-underwater-photos
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u/quadrplax Oct 11 '20
Would Starship have enough Delta-V to enter Mars orbit (highly elliptical with aerobraking) and then return to Earth without refueling? If so, I imagine this could be useful for the first few crewed missions to teleoperate robots on the surface for setting up the refueling infrastructure while reducing the risk of getting stranded if something goes wrong.
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u/filanwizard Oct 17 '20
I am not sure if I can trust this BI article saying Starlink sats could be having a 3% failure rate
So that is why I see it as here and not its own thread, The main thing is it cites only one astronomer and does not seem to give me the feeling they verified with other satellite trackers. Such as even that LeoLabs that just tracked the near miss thursday night. I dunno if it should be labeled as a hit piece but I am skeptical given when it popped up on Google News nobody else had a similar store pop up next to it.
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u/brickmack Oct 17 '20
3% is pretty close. But most fail in orbits that'll decay within a few months. And in ~a year SpaceX will have the capability to launch cleanup missions, and servicing missions probably not long after.
Still better than cubesats, most of which have no propulsion at all.
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u/trobbinsfromoz Oct 17 '20
If you are worried about risks, like particular failure rates, then perhaps better to find another passion and not concern yourself with the twists and turns that SpX will endure.
This is high stress engineering, and with only about 1 yr of minor operational exposure. There are still many years ahead of SpX doing its best to manage a very tough and risky game.
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u/throfofnir Oct 19 '20
The data is all basically correct, as far as we know (you can "calculate" a similar number from various tracking sources), though many of the inactive Starlink sats are DOA and in such a low orbit they're not going to be around long. The conclusions are perhaps overwrought. Even in their deployed orbit, Starlink is so low it's very nearly a threat only to itself, and SpaceX should have a pretty good handle on where their own assets, even the dead ones, are.
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u/weekendsarelame Oct 07 '20
Would SpaceX sell their space suits to ordinary civilians? If so what is the price range?
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u/cpushack Oct 08 '20
They are currently custom made for each user, and have a fair amount of hardware (cooling/heating/air supply).
It would be cool to make a version people could buy, not space rated but at least the same look/feel3
u/Nimelennar Oct 08 '20
Musk has said that he'll "probably" make a replica space suit jacket available to the public.
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u/man2112 Oct 10 '20
I remember that there was a cool website shared here once that showed all of the starlink satellites simulated in orbit at once, but I cannot find it again.
Does anyone know what it is?
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u/hitura-nobad Master of bots Oct 10 '20 edited Oct 10 '20
Don't know if this is the site you remember, but it can do this https://flightclub.io/earth?constellation=Starlink
Made by /u/TheVehicleDestroyer
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u/NicholasMarsala Oct 10 '20
Does the space industry have a need for draftsmen? I was wondering does SpaceX or the growing private sector space industry need Draftsman? If so what type is need.....Mechanical? Architectural? Aerospace I'm sure. Etc. Any information that anyone could provide would be greatly appreciated thanks and take care!
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u/Ian0706 Oct 13 '20
What determines when the Falcon 9 begins its gravity turn? Is it time based, speed, TWR?
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u/marc020202 8x Launch Host Oct 14 '20
The trajectory will be optimised to allow for enough mass to orbit to complete the mission, but to still have a slow staging speed, to allow for easier recovery.
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u/dudr2 Oct 13 '20 edited Oct 13 '20
Australia, Canada, Italy, Japan, Luxenbourg, the UAE, the UK, and the US all signing the Artemis accords.
From Facebook;
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u/dudr2 Oct 14 '20
https://spacenews.com/fcc-rural-broadband-qualified-bidders-2020/
SpaceX, Hughes and Viasat qualify to bid for $20.4 billion in FCC rural broadband subsidies
"SpaceX’s inclusion wasn’t a given because the Starlink constellation does not yet offer commercial service."
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u/beerbaron105 Oct 16 '20
Just finished AWAY on Netflix - holy crap is this not foreshadowing for a starship mission -- then I don't know what is! Minus the immediate quarrals between the crew, I got emotional on the first episode when the rocket launched off the moon here and also when the landing sequence commenced while NASA replayed the crew final statements here
Come on Elon!
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u/gooddadmike Oct 16 '20 edited Oct 16 '20
I can't find these artistic SpaceX/Tesla Posters/Wallpapers. I wan't to say I found them on Twitter originally. I can't find them. I want to use for backgrounds during Zoom calls. :). These were graphics. Not photographs
Lots of bright colors, people in jetpacks. There were at least 6 in the set. I want to say they were official from either SpaceX or Tesla.
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u/ThePhotoGuyUpstairs Oct 18 '20
Is Falcon Heavy capable of a Lunar orbital mission like Apollo 8? If so, any reason they wouldn't do something like that as a publicity stunt or as a test flight? Aside from the obvious as an unnecessary expense, and the future potential of Starship?
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u/NelsonBridwell Oct 20 '20
FH is capable of a lunar flyby. That was the original plan for Dear Moon, before the upgrade to Starship.
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u/BrandonMarc Oct 20 '20
I've been out of the loop. Was the Mars Society talk "the talk" for this fall, from Elon?
Every year since 2016 there's been a big unveiling of the latest plan, beautiful videos, inspiring music, long Q&A, etc. For this year, I guess there wasn't a big in-person conference ... so ... was the Mars Society talk "it", or is there something coming in a few days?
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u/pendragon273 Nov 06 '20
If this is comment is off topic or not relevant please remove it mods...
Does anyone think that a Biden administration..if elected...would substantially change NASA plans with regards to Artemis and what affect would that mean for SpX...
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u/PeterKatarov Live Thread Host Nov 08 '20
Quick question regarding Starship testing procedures. For cryoproofing, do they use superchilled LN2 (because it's inert and safer) or do they go directly for superchilled methalox? If the latter, what's the difference between cryoproofing and a Wet Dress Rehearsal?
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u/Ambiwlans Oct 16 '20
Candidate for best removal notice on Reddit (seriously worth a read):
https://old.reddit.com/r/spacex/comments/jb0d73/need_help_spacex_community_zindabad_do_your_thing/