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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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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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Would it be possible for SpaceX's BFR to return the Hubble Space Telescope to Earth in the future?

Ever since the Space Shuttle retired, there was an unpopular decision to leave the Hubble Space Telescope until it eventually stopped working, since there was going to be no way to return it to Earth. ...
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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 ...
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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 ...
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Why won't Falcon Heavy launch with 100% thrust?

The crossfeed system is not yet realized for Falcon Heavy. Instead, the central booster will throttle down after liftoff and resume "full thrust after side boosters separate". Why would one do that ...
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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 ...
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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 ...
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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 (...
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Cost to move to Mars [closed]

First we must assume that Spacex continues to operate in the same way that its running. Once they start building a colony for people to visit or move to. What do you think it would cost to be one of ...
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What was the 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 ...
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What is Retropropulsion?

In a recent news NASA, SpaceX Share Data On Supersonic Retropropulsion My question is what is Retropropulsion?
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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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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 ...
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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 ...
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Roughly how many self-viewing cameras are present in a Falcon 9 LEO mission?

Watch any of last year's SpaceX LEO satellite deployment missions's broadcasts in YouTube, and you can see views from at least several different cameras. At least two on the 2nd stage nozzle, at least ...
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What light was the Falcon 9 grid fin occulting in todays SpaceX Nusantara Satu Mission live broadcast?

What light was the Falcon 9 grid fin occulting in todays SpaceX Nusantara Satu Mission live broadcast? I backed up the time slider on the YouTube live broadcast and snapped some screen captures, ...
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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 ...
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Regulations preventing SpaceX from saying “no” if OneWeb asked them to launch their satellites?

The Forbes article With A Successful Launch, OneWeb Just Joined SpaceX And Others In The Satellite Internet Race says: This marks a turning point in a new generation of communications satellites, ...
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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 ...
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Would it make sense for SpaceX to launch from Boca Chica and land in Florida (or somewhere else)?

So I remember reading that there's a 15% performance penalty to landing Falcon 9's first stage on the barge, and 30% penalty for RTLS (Return to Launch Site). But of course it would be very ...
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Why the soot pattern on the nosecone of Falcon Heavy side booster?

When a SpaceX booster is landed, we are used to seeing soot deposited all over it, usually in a specific pattern. You can read more about that in this question: Why the strange bands of soot of the ...
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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. ...
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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 ...
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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 ...
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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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What kind of power is referred to in “the…most powerful all-electric propulsion communications satellite ever produced”

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) ...
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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: ...
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Have the Starlink precursor Tintin satellites been talking to each other? If so, how?

Tintin A and B are the first two exploratory and testing spacecraft for SpaceX's Starlink program. It looks like they are in very similar orbits in both space and time, and are probably that way so ...
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Where can I find the TLE of ExseedSat 1, India's first ever private LEO satellite?

On 3rd December 2018, a private Indian company Exseed Space launched it's first ever satellite into space called ExseedSat 1. But I couldn't find the TLE for this satellite. I looked it up on n2yo ...
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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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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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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 ...
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1answer
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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 ...
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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 ...
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Is the Falcon Heavy as loud as the Space Shuttle or Saturn V?

Is the Falcon Heavy Rocket as loud as the older Saturn V and Space Shuttles? I have read that Saturn V and the Space Shuttle were within a few decibels of each other. The newer Shuttle was slightly ...
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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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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 ...
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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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What are the towers around the SpaceX launch pad used for?

I noticed four(?) towers around the SpaceX launch pad during yesterday's aborted launch Image credit NBC News What are the towers used for? Tracking? Radio communications?
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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 is the value of the cross-track angle between the two designated CRS-4 first stage recovery zones?

For the SpaceX Falcon 9 launch on its Dragon/CRS-4 cargo delivery mission to the International Space Station, according to Spaceflight 101, two downrange safety zones have been identified: The SpX-...
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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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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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What is Crew Dragon approaching in this picture?

Crew Dragon (without a crew) just docked to the ISS for the first time last night. Most of the news reports on it are using the below photo. I thought it was supposed to dock to the Harmony module's ...
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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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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 ...
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SpaceX 2nd stage or tumbling satellite? WSW to NE over FL

Around 2040 EST We viewed an irregularly flashing object flying from WSW to NNE (roughly) from Jacksonville FL. Is the SpaceX 2nd stage still up there and if so, would it be tumbling and visible? Is ...
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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 - ...
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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 ...