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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.

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Why does the Falcon 9 use RP-1/LOx and not LH2/LOx?

Why does SpaceX use RP-1 in the first and second stages of their rockets? In my view at least the second stage could use hydrogen as it currently is not being reused. I am aware that you have higher ...
4
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2answers
534 views

Why doesn't carbon fiber overwrapping in LOX catch fire? (watch this video first)

Sir Martyn Poliakoff, also CBE FRS and his team produce a fascinating series of Periodic Videos. In this one they team up with Smarter Every Day's Destin Sandlin to do high speed video of a piece of ...
3
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0answers
74 views

What could be used to associate these fairing halves with their launches?

Eric Ralph's Teslarati article SpaceX’s BFR factory in LA spied with four Falcon 9 fairing halves shows several panoramic photos of the site for the future rocket factory. In it, the author says: ...
11
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2answers
260 views

Plans for ISS crew to enter Crew Dragon?

Are there any plans for ISS crew to enter the Dragon V2 while it is docked during the upcoming Crew Dragon Demo 1 mission?
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0answers
112 views

What is the droplet size that is desirable for pintle injectors?

The pintle injectors tend to generate droplets after impingement of the fuel and the oxidiser stream and I understand that the droplets will be premixed. In such a case, even a larger premixed ...
4
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1answer
184 views

SpaceX nose fairing heating during launch?

In watching the Space-X SES-12 launch last night, I noticed what looked like the nose fairing of the rocket glowing a bit a while after launch. This was most obvious in the video about T+1:30 to T+1:...
6
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3answers
573 views

Will reusable rockets be financially viable?

While the vertical landing of rockets by SpaceX is certainly a significant achievement, there seem to be many who say that reusability is not actually financially viable. Apparently, it is far too ...
4
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1answer
99 views

How far apart do both SpaceX half fairings splash down?

Inspired by this question: How far apart from each other (both in space and time) do the two halves of a Falcon fairing land? I'd also be curious to know what's the error margin they have on this. ...
7
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1answer
190 views

What are these tiles inside the Falcon 9 fairing?

The three photos in SpaceX's recent tweet about attempting to recover the GRACE-FO/Iridium-6 fairing halves included a close-up of the inside of the fairing: [] What do those black tiles with the ...
5
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0answers
958 views

Potential improvement to BFR or New Glenn if equipped with aerospike exhaust on their engines?

Aerospikes basically tackle the issue of the variability in required expansion ratio for a rocket engine to be efficient at a given altitude. A recent example though mired in legal issues is a small ...
3
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1answer
319 views

How does SpaceX decide which half of the Falcon 9 fairing to catch?

Question: How does SpaceX decide which half of the Falcon 9 fairing to catch if they are only going to catch one half? Is one half more expensive and/or well instrumented than the other? Images from ...
4
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1answer
961 views

How much does a current F9 fairing-half weigh?

Question: How much does a current F9 fairing-half weigh? Is this resting on something, or is it really floating this high in the water? Images from this SpaceX tweet: Falcon 9 fairing halves ...
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0answers
168 views

What kind of power does “…most powerful all-electric propulsion communications satellite ever produced” refer to?

The Florida Today article On second flight, SpaceX Falcon 9 rocket to launch 'brute' of a satellite from Cape describes the upcoming SpaceX launch of SES-12. Next to this tiny image of (presumably) ...
15
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2answers
2k views

Why is the first stage from the Falcon 9 SES-12 mission not recovered?

Youtube video here At 4:13 minutes into the Iridium-6/GRACE-FO NASA Launch, the commentator mentions: The first stage is not going to be recovered, so there won't be any views from the drone ship ...
7
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3answers
374 views

What are these circular structures around the rocket?

Youtube video of the Iridium-6/GRACE-FO NASA Launch (Falcon 9 SES-12). Edit 31 May: Too bad they have changed the content of the video (and still call it 'live'), so that you can no longer see the ...
8
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2answers
1k views

BFR ticket cost

Has anyone paid SpaceX for a trip to Mars on the BFR? If so, how much did they pay?
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0answers
156 views

Has SpaceX ever done a hot restart of a 2nd stage?

Another question highlighted this Space X commentary for the GRACE-FO launch: Now in order to fly an efficient trajectory for both of the payloads, we’re actually now running the second stage ...
4
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1answer
78 views

Efficiency and timing of the Iridium-6/GRACE-FO low-power burn and coast phase?

In the video of the recent Iridium-6/GRACE-FO launch at about T+ 08:13 (curently at 24:12 in the video) the announcer says: ...
6
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2answers
323 views

Why did this fairing separation happen at such a high altitude? (SpaceX Iridium-6/GRACE-FO)

I noticed in the video of the recent Iridium-6/GRACE-FO launch that the fairing separation happened at an altitude of about 143 kilometers. This is significantly higher than any altitude I can ...
10
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2answers
189 views

Deploying multiple satellites from one second stage

I’m just watching the Iridium-6/GRACE-FO launch from SpaceX. Before the launch they showed a video of the Iridium satellite network and in this mission they deployed 5 additional satellites into LEO. ...
5
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1answer
175 views

Should SpaceX have 2 versions of the Falcon 9 rocket (cargo-only and human-only)?

I am learning that having a human rated Falcon 9 rocket is very difficult. Would it be better to have 2 versions of the Falcon 9 rocket? I figure a human-only version would be easier to design with ...
6
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1answer
296 views

Do Falcon 9/Heavy Block 5 boosters need landing legs? Or can they land back on their launch mounts?

At 2017's International Astronautical Congress, Elon Musk claimed that SpaceX could master propulsive landing without landing legs. The assertion was that Falcon 9's ...
0
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1answer
259 views

What happens when a rocket explodes (specifically, the SpaceX CRS-7 mission)?

In videos of the SpaceX CRS-7 explosion I've seen, it looks like the explosion vaporized the rocket, since no wreckage/debris made it more than a few feet downward -- tiny little things! But the ...
3
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2answers
259 views

SpaceX Lunar Mission when possibly will it take place in future?

As SpaceX has delayed the crewed Lunar Mission which was going to happen in 2018 and now as currently, BFR is in progress, and also as SpaceX has mentioned in the first half of 2019 it will conduct ...
6
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1answer
168 views

Understanding Flightclub.io simulation of SpaceX's Bangabandhu launch

In this answer I used Flightclub.io's current simulation of the recent Bangabandhu Satellite-1 Mission. The pre-built simulations (you can do your own there as well) are sometimes refined over ...
3
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1answer
115 views

Will Falcon 9 block 5 successful launch speed up production of BFR?

I was just wondering that as Spacex has just launched it's final variant of Falcon 9 block 5 successfully, so now will it speed up the process of building BFR rocket ?
4
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2answers
169 views

SpaceX May 11, 2018 Falcon 9 launch had no boostback burn

One of my questions regarding the May 11 launch is Why no boostback burn? I assume that without such a burn, Stage One would continue on at about 8,000 km/hr in an EASTWARD direction, away from the ...
5
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1answer
83 views

1/st Stage slow down after MECO and separation for F9's

Once the Falcon 9 Full Thrust 1st Stage reaches "MECO" - main engine cut off - and separates from the 2nd Stage how much velocity does it lose? Specifically at "MECO" its velocity is approx. 5,900 km/...
5
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1answer
317 views

What caused launch abort on SpaceX's Bangabandhu-1 launch

On Thursday, May 10th, 2018, SpaceX attempted a launch of the first Falcon 9 block V rocket carrying Bangabandhu-1 however the countdown was stopped at t-58 seconds and the launch was scrubbed for 24 ...
3
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0answers
60 views

Is it possible for a space rocket to escape a planet's gravity if the gravity was 10 times that of earth? [duplicate]

I know that the scenario isn't realistic but lets assume that we have a planet which is identical to ours except that it's gravity is 10 times bigger. Would it be possible to launch a space rocket ...
5
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1answer
190 views

Silly concept: repurposing BFS into a spin-gravity habitat

The idea is the following: Launch four passanger carrying (but empty) BFS and a fifth, (satellite deploying version) which carries the central hub, outfitted with spin-up engines. Then manouver the ...
6
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1answer
214 views

How long will ISRU process take on Mars to refill the SpaceX ship there?

Here was clarified how but not how long: How will the SpaceX ITS return from Mars? Because, for that time in case everybody wants to return you need to support survival on Mars (the ship is stated ...
10
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1answer
471 views

What improvements does SpaceX Falcon 9 Block 5 have over prior version?

Does SpaceX disclose what improvements their Falcon 9 Block 5 will have over the Block 4 model? If so, what improved features will it have? I have heard general comments about it in the news, but I ...
13
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2answers
3k views

Getting the SpaceX dragon crew rated

Since the Dragon craft is already pressurized why is taking it so long to get it approved to carry a crew?
11
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2answers
2k views

Can SpaceX Falcon 1st stage hover during landing?

I came across with this video in which the Falcon Heavy boosters' landing burn seems to deaccelerate the 1st stage until a point their speed is constant right before touchdown. ...
23
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2answers
7k views

Does launching a device into orbit change earth's orbit?

Does launching a space shuttle or rocket change the earth's orbit? After all, to get momentum in space you need to throw something out.
18
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1answer
5k views

Why is Falcon 9's fairing so big?

The Falcon 9 fairing costs millions of dollars. It is 5.2 meters wide while the rocket itself is only 3.7 meters wide. There is no aerodynamic reason that the fairing has to be so big, since Dragon ...
10
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1answer
311 views

Are all payload fairings this floppy?

When I watched the launch of HYLAS-4 and Superbird-B3 on Ariane 5 ECA, for a moment it seemed that ESA is also experimenting with fairing recovery - with a fairing which flaps its wings and flies like ...
2
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0answers
43 views

How much would the James Webb Telescope have cost of they made two or ten of them instead for example? [duplicate]

How much could you cut the price by "mass" producing (at least more than one sample) explorer spacecraft (Galileo, Cassini, New Horizon, Dawn...), space telescopes (Kepler, TESS...) and satellites? ...
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0answers
91 views

How can a company or a person reserve an orbit for a satellite? [duplicate]

How can a company reserve an orbit for a communication satellite? And are there any companies which provide an orbit leasing service?
16
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2answers
3k views

Why will the BFS reenter broadside rather than engine first?

Musk has stated that they added the delta wing to the BFS design because; from one flight to the next the ship may have differing payloads and differing fuel loads. These changes shift the center of ...
4
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2answers
142 views

DragonFly Propulsive Testing

When is SpaceX's DragonFly propulsive landing technique likely to be demonstrated as part of a real landing, rather than the simple test shown below (from here)? What will be the key objectives for ...
2
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2answers
180 views

SuperDraco Engines in Crew Dragon spacecraft

How can a single spacecraft namely Crew Dragon aka Dragon V2, accommodate 8 SuperDraco thrusters along with sufficient propellant required for a precision propulsive landing and/or other such ...
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1answer
139 views

Merlin 1D Engine [closed]

How does the Merlin engine work? How does it's working compare to the working of SuperDraco engine? To be more specific, What features of Merlin make it unique and more efficient than other rocket ...
3
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1answer
533 views

Is it feasible to launch NASA's InSight mission Mars using a Falcon 9, instead of an Atlas V rocket?

The Insight mission is launching the spacecraft to Mars on May 5th aboard the Atlas V rocket by ULA. Would it have been possible to launch this mission using a SpaceX Falcon 9 Block 3/4/5 (expendable ...
30
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3answers
7k views

Why won't they recover the Falcon 9 from CRS-14?

According to the upcoming livestream of SpaceX CRS-14 (resupply of ISS): SpaceX will not attempt to recover Falcon 9’s first stage after launch. Why not? Wasn't that the whole point of (among ...
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2answers
343 views

SpaceX Raptor engined first stage landing

Reusability is a key strategy for SpaceX to lower the cost of orbital and interplanetary launches. With the Falcon 9 they are using the powered landing approach to recover the first stage for reuse. ...
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0answers
32 views

Is elon musks car in space getting over heated being in the sun? [duplicate]

Is the car elon musk put in space getting hot being in the sun?
3
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1answer
131 views

Is a soot covered flight proven Falcon 9 lighter or heavier than a new falcon 9?

Since SpaceX now does not repaint or clean off the sides of the first stage booster prior to reuse, does this make the soot covered stage heavier or lighter? And is this difference in weight ...
51
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3answers
16k views

Why would NOAA restrict the ability of SpaceX to live stream the second stage?

I was watching the live stream of the Iridium-5 launch and they mentioned that NOAA had restricted their ability to live stream the second stage and that SpaceX was working to remove this restriction. ...