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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6
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1answer
64 views

Orbital insertion accuracy for SpaceX payloads

What is the orbital insertion accuracy of SpaceX for positioning its payload (for example satellites)? How close do they get to the requested or target orbital parameters? I tried to research this on ...
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What's this purple donut in the video of the Falcon 9 fairing's atmospheric reentry?

This SpaceX tweet (found in CNET's SpaceX camera captures incredible view of rocket part returning to Earth) shows a video taken by a camera in one half of the fairing on the recent STP-2 mission and ...
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1answer
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Is SpaceX propulsively deorbiting a Starlink satellite already?

The plot below shows that most of the SpaceX Starlink satellites have moved from circa 450 km to circa 550 kilometers already, using their argon-based ion engines. A few, along with four unidentified ...
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Why doesn't the SpaceX web-cast show the telemetry, (altitude and speed) for the first stage during recoveries?

On the YouTube videos of SpaceX launch operations, they show altitude and velocity for the 2nd stage throughout the flight, but after stage separation I have never seen telemetry displayed for the ...
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5answers
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Why doesn't SpaceX land boosters in Africa?

Apart from the obvious answer that it'd take too long to get the booster back across the Atlantic, why doesn't SpaceX leave the main or centre booster in space a little bit longer and guide it to land ...
7
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1answer
188 views

Did the Falcon Heavy center core miss the drone ship or abort?

On the recent Space Test Program-2 Falcon Heavy launch, the center core crashed into the ocean. Unlike the test flight, however, it was not due to running out of TEA-TEB lighter fluid. From the video ...
16
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5answers
5k views

Reusable spacecraft: why still have fairings detach, instead of open/close?

Why do reusable rockets (e.g. SpaceX Falcon 9) still utilize detachable fairings? SpaceX keeps trying to find a way to recover the $6M fairings for obvious cost saving reasons, why not have them ...
2
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1answer
79 views

Are there payload lights turning on and off in orbit on SpaceX STP-2?

In the video of the SpaceX STP-2 Mission during satellite deployment after around T+01:21:35 there are some areas that abruptly blink brightly. It's too fast and ...
8
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2answers
442 views

Does flying two boosters close together affect efficiency?

When returning the side boosters of the latest Falcon Heavy launch to their landing site, their trajectories keep them right next to each other, and I noticed that a "wall" of vapor is visible midway ...
4
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1answer
131 views

Would SpaceX's Starlink constellation contribute inordinately to space debris?

I mean they already launched a large constellation of 60 satellites and have plans to launch many more; won't all this contribute inordinately to existing space junk, which is actually becoming a real ...
7
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1answer
112 views

How much of the recovery system does Spacex remove from a Falcon 9 when using it in an expended manner?

Falcon 9s have a limit to how many times they can be reused, and, for the last flight of a booster they don't make it land (in one piece), and instead use all the fuel to help the payload. That way ...
6
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2answers
280 views

Why does the F9 second stage roll back and forth during deployment of each RADARSAT satellite?

GIF Watching the SpaceX video RADARSAT Constellation Mission after T+ 52:00 we can see at least the first two satellites deploy. In each case, the second stage ...
5
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144 views

What are these four “debris” objects along with the Starlink satellites?

Celestrak has an updated system of categories for retrieving lists of current TLEs, and there's already one for Starlink, yay! Currently https://www.celestrak.com/NORAD/elements/starlink.txt contains ...
3
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81 views

How much do SpaceX's titanium grid fin geometrical parameters measure?

Does anyone know approximately what is the width, length, thickness and depth of the titanium grid fins used in the Falcon9 v1.1? I'm trying to make a 3D model on solidworks but can't find the ...
3
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1answer
142 views

What are Starlink's available momentum unloading strategies?

Today's Teslarati article SpaceX wants to offer Starlink internet to consumers after just six launches talks about the new website https://www.starlink.com/ shows several images from it, and tries to ...
2
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1answer
184 views

Delta-V of Starlink Satellites

The recently launched Starlink satellites are designed to use their HAL Ion thrusters to seek their own independent orbits, evade collisions, and de-orbit at the end of their lives. That's a lot of ...
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What is the function of this Merlin engine's tube, and why is it getting red hot?

In the video of the recent SpaceX Starlink launch, one view of the Falcon-9 2nd stage engine shows a cane-shaped tube that glows red hot at the "handle" end and seems to get hotter over time. ...
10
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2answers
1k views

Is the Starlink array really visible from Earth?

I was browsing YouTube when I came across this video, recorded from a sky gazer who apparently spotted the Starlink satellites. In my lifetime, I haven't seen many satellites in the night skies (maybe ...
2
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What caused these strange lights around the Falcon 9 grid fins (Starlink launch)?

Early in the video of the launch of the first sixty SpaceX Starlink satellites we can see that after stage separation the first stage grid fins open. Around that time there are some phenomena I don't ...
4
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2answers
97 views

Shortest ever F9 2nd stage burn for the largest ever F9 payload? (Starlink Mission's SES-2 burn time of 3 seconds)

According to the SpaceX broadcast the first SpaceX Starlink launch (24-May-2019) is notable for reasons including being the heaviest ever Falcon 9 payload to date. At roughly ...
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2answers
390 views

What performance specification would be lower for Krypton than for Xenon in Hall effect thrusters?

The Ars Technica article SpaceX scrubs first attempt to launch 60 Internet satellites [Updated] (found here) discusses the use of Krypton rather than Xenon in the Starlink Hall effect ion thrusters: ...
11
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2answers
301 views

What does this SpaceX tweeted photo show and what causes the pure red and blue color?

This May 4, 2019 SpaceX tweet says More photos from Falcon 9’s 40th successful launch from Pad 40 in Florida and 39th first stage rocket booster landing to date → http://flickr.com/spacex and ...
7
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1answer
336 views

How will Starlink satellites deploy from the fairing and reach their orbits?

Elon Musk posted this picture of the first 60 Starlink satellites packed densely into the fairing of the Falcon scheduled to launch in a few hours. There doesn't appear to be a launcher or ejector to ...
7
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2answers
2k views

Why will Starlink satellites use krypton instead of xenon for electric propulsion?

The press kit for the first Falcon 9 Starlink launch and deployment of the first 60 satllites scheduled for May 15, 2019 says: With a flat-panel design featuring multiple high-throughput antennas ...
3
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1answer
158 views

How will Starlink satellites be capable of tracking on-orbit debris and autonomously avoiding collision?

The press kit for the first Falcon 9 Starlink launch and deployment of the first 60 satllites scheduled for May 15, 2019 says: Starlink satellites are capable of tracking on-orbit debris and ...
3
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1answer
193 views

Can we get to Mars today using current rockets/technology?

I was wondering if, using the rockets we have today (I'm guessing the most likely candidate is the Falcon Heavy), we could send at least 1 human to Mars. For arguments sake, let's ignore the fact it ...
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286 views

Why is SpaceX's Raptor's design so simple in comparison to SSME?

What is especially striking to me is how simple Raptor is in configuration compared to SSME. The Raptor doesn't have an LP fuel or oxygen pump. What's even more surprising, if we are to compare the ...
3
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1answer
137 views

When Falcon 9's stage 2 engine fires up, does the flame of the engine affect stage 1 in any way?

Are there any specific design considerations that are made over nonreusable, traditional rockets to tolerate the blast from the stage 2 engine? As shown in this moment:
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2answers
253 views

Is this Falcon 9 on a drone ship in Port Canaveral on fire?

The Teslarati article SpaceX’s latest Falcon 9 booster returns to port as NASA hints at “vested interest” shows this tweet about booster number B1056 from Jennifer Krafft Photography: #SpaceX #...
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What object is visible in the background of the Dragon view from the CRS-17 launch?

In the livestream of the CRS-17 Mission, at 28:02 into the livestream (T+13:02) there is a flashing object visible in the bottom, left third of the screen. This object moves "up" in the frame. It is ...
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73 views

Books on Vertical-Landing Vertical-Takeoff (VTVL) of Rockets? or Rocket Design in General?

I am working on a rocket control system design and I am trying to understand the the fundamental principles and concepts to design an efficient controller for recovering and landing the rocket, ...
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38 views

Is there video from the Falcon second stage of the Dragon solar panels deploying?

We get video from the second stage of the Dragon leaving the second stage. And we get video from the Dragon of its solar panels deploying. But a cool view would be of the Dragon's solar panels ...
4
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1answer
450 views

SpaxeX employees on the droneship when the booster lands?

SpaceX is doing a great job in recovering the boosters from its rockets. The Falcon Heavy has 3 boosters. 2 of which land at Cape Canaveral and 1 on a drone ship somewhere in the ocean. Are there ...
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2answers
1k views

Why does the Superdraco exhaust seem so under-expanded in this photo?

The Ars Technica articles From zero to 100mph in 1.2 seconds, the SuperDraco thruster delivers Dragon was destroyed just before the firing of its SuperDraco thrusters both include this "file photo" ...
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2answers
144 views

How will Mars terraforming missions really work, how do pioneers like SpaceX plan on conquering Mars? [duplicate]

We know Mars is now dead in the water (or space), it is now merely an oversized rock hurtling through space, with a bit of atmosphere. I was reading up on terraforming the planet, and learned that ...
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58 views

Most challenging aspects of a reusable satellite scheme like this?

What would be the most challenging aspects of a reusable satellite scheme similar to the one shown in this video? For the kilo-constellations (e.g. SpaceX's StarLink with 4,500 to 7,500 satellites) ...
4
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1answer
182 views

What does the StarLink constellation look like now? Numbers of planes and inclinations?

In the question SpaceX's 4,425 satellite constellation - what's the method to the madness? I took the orbital parameters in SpaceX's filing SpaceX non-Geostationary Satellite System Attachment A - ...
2
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1answer
130 views

How to judge the compatibility and veracity of Scott Manley's explanations for the SpaceX AMOS-6 anomaly?

I was recently caught off-guard by a proposed explanation for a SpaceX malfunction which seems to have turned out to have been a joke at probably my expense and no-one else's, meaning I completely ...
5
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2answers
247 views

Could Falcon 9 take off without launchpad

As far as I'm currently aware, the Falcon 9 block 5 does not have the capability to retract it's landing legs once they're deployed, however: If F9 landing legs had the ability to retract themselves (...
5
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1answer
406 views

What exactly happened to crew dragon on 4/20?

The crew dragon experienced an anomaly yesterday during testing. It seems that there was some sort of unexpected event that resulted in damage to the crew dragon test article. This unconfirmed video ...
3
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2answers
425 views

How could a hydrazine and N2O4 cloud (or it's reactants) show up in weather radar?

Question: How could a hydrazine and N2O4 cloud (or it's reactants) show up in weather radar? Tweet: This is what an ‘anomaly’ looks like on weather radar. Tweet (with GIF): Dragon's static ...
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How many SpaceX 2nd stages are in heliocentric orbits?

I can think of one particularly famous SpaceX 2nd stage in heliocentric orbit that even has its own website: https://www.whereisroadster.com/ and I know one was used to send DSCOVR towards Sun-Earth ...
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1answer
166 views

Why is DSX two satellites connected by a ring, and what are all those tubes? (upcoming SpaceX STP-2 payload)

Reminiscent of a chrome-plated exhaust manifold from a 20th century vehicle. The Teslarati article SpaceX’s Falcon Heavy flies a complex mission for the Air Force in launch video discusses the ...
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6answers
3k views

What is “propulsive passivation” and why will the SpaceX STP-2 mission do it?

The Teslarati article SpaceX’s Falcon Heavy flies a complex mission for the Air Force in launch video discusses the upcoming third Falcon Heavy mission STP-2 and quotes the caption on the linked ...
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1answer
215 views

What barge height limit warning sign is Scott Manley describing? (Falcon Heavy core fell into ocean)

In the beginning of Scott Manley's new video The First Commercial Lunar Spacecraft - 20 Years before Israel & Beresheet he takes a moment to talk about recent Falcon Heavy core falling off the ...
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1answer
2k views

Why did the Falcon Heavy center core fall off the ASDS OCISLY barge?

On the second flight of the Falcon Heavy, they successfully landed the side cores at LZ-1 and LZ-2, and the center core downrange on the ASDS Of Course I Still Love You. Reports have come in that ...
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0answers
118 views

Could the BFR Tanker be used as an artificial gravity counterweight for interplanetary travel?

An alternative storyline to the Mars transport architecture: Tankers refuel starship, last Tanker gets mounted on the Starship for the Mars orbital injection burn, once on a Martian trajectory tanker ...
6
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1answer
477 views

Does the US Navy guard SpaceX drone ships and make sure bad actors don't abscond with critical technology on the high seas?

SpaceX loses the center core of its Falcon Heavy rocket due to choppy seas While I thought my question How vulnerable could space launch vehicles be to a “lone gunman”? was just my tangential ...
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0answers
88 views

SpaceX Canaveral launch question

In the past, I could see space shuttle launches from my front door on the gulf coast of Pinellas County by looking due east on a clear day or night. I have tried to catch SpaceX launches a couple ...
8
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1answer
221 views

What is known about these early Falcon XX concepts?

I came across this page with the following picture from 2010: I must say the Falcon X, Falcon X heavy and Falcon XX look rather interesting. Does anybody know of resources that explain the intended ...