Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [spacex]

Space Exploration Technologies Corporation, or SpaceX, is a private space exploration company. It was the world's first privately held company to successfully launch a cargo mission into space.

3
votes
3answers
198 views

Will it be possible to see BFR approaching the moon from earth, with naked eye?

The title pretty much sums it up. I'm not old enough to have experienced any of the previous manned moon landings. Given that Big Falcon Rocket will go around the moon in 2023, I'm wondering if one ...
5
votes
1answer
76 views

How low is VLEO? (FCC's newest approval for SpaceX)

Engaget's SpaceX gets FCC approval to deploy thousands more internet satellites says SpaceX's plan to build a global, high-speed wireless internet network using satellites has taken another step ...
9
votes
1answer
144 views

What is the mysterious cube shaped object observed in the Falcon 9 launch? [duplicate]

For today's(November 15 2018) Falcon 9 launch, at around T+ 06:04 into the mission, we can see a cube shaped object flying near to Falcon 9 first stage. This ...
4
votes
0answers
54 views

Purging process of a rocket engine

Does spacex purge Falcon 9 engines after landing ? If so, which gas is used for purging?
-2
votes
1answer
157 views

Shape of Dragon Crew capsule affecting ballistic descent?

\ I I don't think anyone has the seen the actual dimensions of dragon version 2, but assuming it is what SpaceX will be using to take people to space, I think it will have issues regarding stability ...
6
votes
1answer
188 views

How does falcon-9 engine survive while re-entry burn without chilling ?

I've often seen that in launch sequence, "engine chilldown". I've learnt that chilling is done to avoid thermal cracking in plumbing lines and also to avoid cavitation. While re-entry, do they ...
4
votes
0answers
57 views

Chilling during restart of Spacex first stage engine [duplicate]

As I know that all the liquid rocket engines go through chilling process for different components (like pipes, engine, injector plate, etc.) before starting the ignition. At the time of launch the ...
4
votes
2answers
322 views

How does SpaceX plan to make money with StarLink Broadband?

To me, it seems obvious that ground based optical fibres will be cheaper than a space based system by an order of magnitude. So unless say, everyone starts sea-steading and a space based broadband is ...
1
vote
1answer
57 views

Can VTVL rockets use dampers like high rise buildings to provide stability?

VTVL with long and thin body have a difficult time in obtaining stability during landing. Watch this failed SpaceX rocket landing for example: Why can't they use "...
1
vote
0answers
43 views

Temperature indicators/labels on space debris?

There was a picture in this question about space debris on shore. Seems to be a part of a Falcon 9. The round stickers are used for temperature control. Similar labels are sold by some companies, for ...
0
votes
1answer
123 views

Analytical approximations for the shapes of these plots of ISP vs nozzle diameter? (Raptor engine)

A comment on the currently unanswered question Is there an authoritative catalog for rocket launch identifiers? led me to this Github page which links to r/spacexlounge on which currently appears a ...
4
votes
1answer
221 views

Why Elon chose the rocket-launching part of the space market?

The projected future value of the entire market related to spaceflight is Astronomical! I've seen USD 280 billion mentioned for example. The rocket-launching part of that is a small fraction, perhaps ...
4
votes
2answers
68 views

what's this fluffy object on the SAOCOM 1A mission's upper stage? [duplicate]

When watching the upper stage of the Falcon 9, I noticed this white or blue tuft: It changes shape a bit as time goes on. That makes me think it is something very light (cotton candy, fiberglass ...
4
votes
1answer
73 views

Does a retrograde launch impact the return booster propellant requirements, as compared to prograde?

Space-X's latest launch, of SAOCOM-1A, was a retrograde launch from Vandenberg, with a landing back at Landing Zone 4 - at Vandenberg. A retrograde launch requires more energy (to counteract the ...
3
votes
1answer
174 views

How do you shut off a Merlin-like rocket engine quickly? How quickly can it be done?

After about 36:17 in part 1 of this recording of SpaceX's Hans Koenigsmann's talk at IAC 2018, he narrates the propulsive landing of a Falcon 9 first stage, and ...
2
votes
1answer
576 views

What flame is SpaceX's Hans Koenigsmann describing in his presentation?

At 35:46 in part 1 of this recording of SpaceX's Hans Koenigsmann's talk at IAC 2018, he says something like: The green stuff that you see is TEA-TEB, that’s the ...
1
vote
1answer
92 views

Will SpX-DM1 (Crew Dragon demo mission) carry any useful cargo (supplies)?

To adequately simulate crew transport, the Dragon 2 should at least carry mass simulators of mass equivalent to that of the astronauts. Will it? Will it be dummies or some useful cargo? Would be a ...
4
votes
0answers
109 views

Fuel carried by current Crew Dragon

How much fuel weight will the current Crew Dragon carry? Will it be just enough for launch abort, or the full load (over 3000 lbs) needed for propulsive landing as a back-up to the parachutes? I ...
5
votes
1answer
158 views

Would a Martian landing and take off require a flame trench/deflector?

Flame trenches/deflectors are essential for avoiding reflections of acoustic waves from damaging the rocket system while taking off. This is discussed in this YouTube video - Why doesn't the sound of ...
2
votes
1answer
87 views

How far has Artificial Intelligence (AI) came in satellites? [closed]

Are AIs being used in satellites? If yes, have they learned to adapt in satellites? In what way AI has benefited space exploration for us?
11
votes
1answer
211 views

How does SpaceX plan to deal with boiloff on the trip to Mars?

Both BFR booster and BFS are to run on Raptor engines, fueled with liquid methane and liquid oxygen - cryofuels. The trip to Mars will take at least a couple months, and BFS requires fuel for powered ...
5
votes
3answers
1k views

Will spacex launch in an inclined fashion while returning from mars?

Considering the toughest thing in launching a rocket is to achieve the tangential velocity, launching horizontally might give us an added advantage for delta V requirement. This can't be done in ...
1
vote
1answer
151 views

Could an inflatable heat shield be used on the SpaceX Mars Lander?

Could light weight inflatable heat shields be used like parachutes from NASA to increase surface area for the SpaceX Mars lander further decreasing velocity? Where would be the best placement of them? ...
2
votes
2answers
187 views

Does anyone know how the Flight Club website simulates Falcon 9 launches?

Does anyone know how the Flight Club website is able to provide falcon 9 launch simulations? Given the estimated weight, fuel mass, thrust, ect, how are they able to provide a graph of how it could ...
1
vote
1answer
135 views

Which one of these (if any) is the Moon? What are the rest?

I frequently see the Moon in SpaceX videos, "I suspect" the frequency is higher than random, but can't prove it (yet!) I found the SpaceX video Falling Back to Earth | HD Footage From Space (also ...
6
votes
1answer
255 views

Can BFS land on the Moon?

Can BFS land on the Moon and return? No aerobraking, no ISRU resources to refuel on the surface for return, but much less delta-V than going to Mars. Landing legs are there, though the engines may be ...
6
votes
2answers
231 views

What would the BFS' landing on Mars be like, if it is different from this animation?

The question What is the terminal velocity on Mars? and its answer has got me rethinking the BFR's reentry and propulsive landing simulation/animation shown in the recent SpaceX video First Private ...
4
votes
1answer
150 views

What is this “space ring”? Is it SHERPA or something new, or just “art”?

In the orbitalreflector.com website there is a picture of a ring that looks like it can deploy smallsats as part of a more complex launch. Reverse image search turns up another view, both shown below. ...
0
votes
0answers
104 views

Avionics Systems on board Falcon 9 (Reusable)

What kind of control systems are active and how do they function on board a Falcon 9 booster while it's landing ?
5
votes
3answers
1k views

New BFR Engine arrangement

Watching the announcement at Space X I was confused about the new engine arrangement. All the nozzles look the same size. Is there still a mixture of vacuum engines and sea level engines? Or did they ...
4
votes
3answers
1k views

Will SpaceX's moon mission carry any engineers to fix the craft or will the artists be trained for these operations?

In the live stream, Elon Musk mentioned that a dozen would be the ideal size for a mission. Could have easily been an off the cuff range, but would allow for some engineers if something goes wrong. ...
2
votes
1answer
127 views

How the new BFS is supposed to dock for refuelling?

The previous design iteration of BFS called for flat tails to connect the tanker and the passenger version and facilitate propellant transfer through acceleration. But the new version is depicted to ...
2
votes
2answers
178 views

Why Spacex Lunar Mission date postponed?

Previously SpaceX Lunar mission date was 2022, but it is mentioned in the wiki that it is no earlier than 2023. Why the date has been postponed?
5
votes
0answers
85 views

Why is heated Helium used for tank pressurisation in Falcon 1?

Here in Falcon 1 user guide, in table 2-1 in page 8, heated Helium is mentioned as used for tank pressurisation. What will be the temperature of such He and why is heated He used?
3
votes
1answer
273 views

What is the thickness of the Falcon 9 - Electron outer casing (outer shell)?

What is the material of the Falcon 9 outer casing/electron shell, and what is the technical jargon for that specific part?
1
vote
1answer
178 views

Is it possible to calculate Max-Q without having to input an altitude

Is it possible to calculate max-q based on just upwards velocity instead of specially inputting a given altitude/air density? Based on this graph of Falcon 9 launches till MECO below "Air Pressure vs. ...
5
votes
2answers
705 views

Is SpaceX lunar mission only a flyby mission, or it is going to land on Moon too?

Is SpaceX lunar mission only a flyby mission, or it is going to land on Moon too?
2
votes
1answer
115 views
3
votes
3answers
191 views

3* Tonnes Unaccounted for in Falcon 9 FT Weight Wikipedia Calculation?

On the Falcon 9 FT Wikipedia page, the fully fuelled weight of Falcon 9 is only 546 300kg instead of 549,054kg as stated on SpaceX website. 546,300 kg - Wikipedia ...
1
vote
1answer
85 views

What is the Kerosene/LOX mixture ratio of the Block 5 Falcon 9?

as the title would suggest, does anyone know a calculation or solution to finding the current mixture ratio used on the latest block 5 configuration? This would be easier if so many people did not ...
7
votes
2answers
533 views

Does anyone know how to calculate the KG per second of RP-1 and LOX from the 9 Merlin 1D engines?

as can be seen from the title, I have been through at least 1,000 chrome tabs in the last few hours trying to find some form of definitive answer, but I've found absolutely nothing. Could anyone help ...
4
votes
0answers
62 views

What sort of ambient air density was there when/were Starman/Roadster first started playing Bowie's “Life on Mars”

When the Falcon Heavy test flight 2nd stage fairing opened at about 115 km, David Bowie started singing "Life on Mars". Okay, the Tesla Roadster's stereo started playing "Life on Mars", or at least ...
32
votes
3answers
7k views

What is the primary reason for SpaceX motion to have astronauts board Dragon before fueling up the rocket?

News piece: NASA supports SpaceX plan to fuel rockets with astronauts on board. The move is criticized by many as unnecessarily dangerous. From what I understand though, it shouldn't be necessary - ...
25
votes
1answer
4k views

Would this chair support astronaut during launch in Crew Dragon

Recently reporters were allowed to take pictures of Crew Dragon and the SpaceX flight suit. Among them is this picture: I was under the impression that: Chairs needed to be custom molded / adjusted ...
4
votes
5answers
308 views

What if anything makes launching a recovered SpaceX rocket from a drone ship implausible?

Since SpaceX lands their rockets on drone ships (aka ASDS, barges), I'm curious what if anything would prevent rockets from being relaunched from the ship. Obviously the ship would need ...
5
votes
0answers
82 views

Does the downrange position of an ASDS vary, depending on payload mass?

SpaceX in its recovery attempts can either do a Return To Launch Site (RTLS) or land downrange on an ASDS landing barge. The Telesat 19V and 18V payloads were some of the heaviest payloads on the ...
3
votes
0answers
43 views

What are the chances that the ISS transits the moon as seen from your house (or headquarters)?

In this answer I tried to do a simple probablistic estimate on the distribution of the ISS's ground track passes over Earth's equator. Recently there is a photo of the ISS passing over SpaceX ...
2
votes
0answers
62 views

Falcon fairing half - between separation and parachutes deployment

How does Falcon fairing half behaves in atmosphere before parachutes deployment? What is its free fall attitude in atmosphere? Is the fairing's attitude stable (with some wobbling, but without ...
1
vote
1answer
105 views

Would having the Falcon fairing reconnect be possible/beneficial?

I understand that many of the problems with recovering the two pieces of the Falcon 9 fairing deal with the weird aerodynamic patterns of the descent. It is by no means an aerodynamically sound object ...
2
votes
1answer
263 views

Why doesn't SpaceX deploy some module to cover whole fairing like a rain coat just before sea landing? [duplicate]

In order to avoid fairing to get wet in water, why can't SpaceX just deploy something such that when fairings separate from the Falcon 9 then from inside some raincoat type waterproofing to just cover ...