Questions tagged [landing]

Questions regarding the specific part of flights, during which a spacecraft touches down on the solid ground of a celestial body.

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73 views

How do you calculate burns needed to land?

Assume I was landing a rocket and wanted to do calculations on how to correctly land. How do you determine at what time you fire the engine and at what power to successfully land on a predetermined ...
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How did the Vostok ejection seat safely eject an astronaut from a sealed space capsule?

Wikipedia's Yuri Gagarin says: At about 23,000 feet (7,000 m), Gagarin ejected from the descending capsule as planned and landed using a parachute. and the section Vostok_programme; Vostok 3KA ...
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How exactly were solid-fuel rockets added to the parachute lines of the Voskhod capsule?

This answer notes that Voskhod: ...added a small solid-fuel rocket to the parachute lines. It fired as the descent module neared touchdown, providing a softer landing. How exactly did they safely ...
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When did soviet capsules begin using retropropulsion immediately before landing?

Wikipedia's Yuri Gagarin says: At about 23,000 feet (7,000 m), Gagarin ejected from the descending capsule as planned and landed using a parachute. and the section Vostok_programme; Vostok 3KA ...
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How do flags behave on the Moon?

I have seen many theories and question/answers on this site touching upon this subject but no focused question. So I would like to ask this as a two part question. Is what we saw in the Lunar ...
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1answer
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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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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 (...
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Could a Rotary Rocket charge a super capacitor while descending on Mars?

Could a rotary rocket entering the atmosphere collect enough energy in a super capacitor through the rotors (along with auto rotation) while descending to have a controlled landing in the last few ...
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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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What is the physics behind a rocket landing on a celestial body with an atmosphere?

I would like to know the different physics concept I would need to land a rocket being in orbit. I know the timing is important to leave it, how can one find this out ? Then how to compute the ...
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Falcon 9 Landing Speed

I wanted to know what the fastest speed is that a Falcon 9 can land at and thus the max force the landing legs can withstand. I assumed the mass when landed is 26,000 kg (I once heard that somewhere). ...
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How does New Shepard Crew Capsule sense proximity to trigger retropropulsion just before impact?

How does the New Shepard Crew Capsule sense proximity to the ground in order to trigger retropropulsion just before impact? GIFs from Blue Origin NS-10: New Shepard launch & landing, 23 January ...
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Why does this boat have a landing pad? (SpaceX's GO Searcher) Any plans for propulsive capsule landings?

The BBC News article SpaceX Dragon demo capsule set to return to Earth talks about the return of the first Crew Dragon capsule to Earth: Four parachutes should bring it into soft contact with water ...
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Is there a practical maximum size for a space capsule returning to Earth?

Assuming I need to get a large cargo or a lot of people safely to Earth's surface in one go in a single-use capsule of the Apollo CM / Soyuz descent type but larger, and assuming that the capsule is ...
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Where is the debris in the Hayabusa 2 touchdown video coming from?

In the video of the touchdown of Hayabusa 2 (https://www.engadget.com/2019/03/06/hayabusa2-probe-ryugu-touchdown-video/) no debris is visible until touchdown. After that, there is a lot of it (though ...
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Can the SpaceX Dragon 2 crew vehicle still use the draco and super draco thrusters to slow down when landing?

In an emergency, is it possible to use the draco and super draco thrusters alone to slow down the vehicle after re-entry? Right from the point parachutes are supposed to be released right upto touch ...
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What systems were used onboard Buran to determine its position during reentry and landing?

Since Buran has managed to return without crew on board, I assume computers had to know its position relatively accurately as it approached the runway for landing. How was this achieved?
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How did Chang'e-4 hover, rotate, and then descend so gracefully? (Video)

In this incredible video we can see Chang'e-4 in it's final approach and landing on the moon from the point of view of the spacecraft. The view is horizontal as the spacecraft seems to stop and hover ...
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Is helium used to power the Falcon 9 grid fins?

Is helium used as a hydraulic fluid to power the grid fins? Or for engine gimbaling? What are the pros and cons of using helium instead of hydraulic fluids?
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Was splashing down on the USSR-controlled territory a possibility for Apollo missions?

From what I understand, the planned landing areas for Apollo command modules were pre-programmed beforehand and happened in the South Pacific. Was there any remote possibility of an emergency ...
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How are Launch Ascent Trajectories and Reentry Constraints Being Implemented these days?

Historically, endoatmospheric guidance for launch ascent has been open loop and suboptimal. Recently, however, it seems as though there has been renewed interest in determining optimal endoatmospheric ...
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How many engines are restarted for landing the falcon boosters

For landing the boosters, it is clear that SpaceX is using the center engine, but I suspect that igniting one engine will not be helpful. If they aren't igniting all the 9 engines, how are they ...
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Falcon 9: how much fuel is left on a booster after stage separation?

If the booster attempts either land or sea landing, how much fuel (RP-1 and LOX) is left in its tanks right after stage separation? Recently, I have heard numbers as high as 30% of its total tank ...
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Why the big difference between NASA and ESA/Roscosmos in evaluating the Oxia Planum landing site?

In november 2018 ESA announced that the Oxia Planum region is favoured for the ExoMars surface mission. The figure above from this answer about the 21 potential landing sites for the Mars 2020 ...
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Could SpaceX's grid fins be controlled by electric motors instead of hydraulics?

There have been a few instances of landing failures related to the grid fins and their hydraulic control - one where the hydraulic fluid ran out, and the latest one where a hydraulic pump stalled. ...
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Why did they not use the Flight Termination system on CRS16 booster?

All US boosters (I assume other nations as well) have flight termination systems. The goal is to try and stop an out of control booster (Big vehicle, full of explosives/fuel/oxidizer) from causing ...
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Falcon 9: engines stabilize spin

On CRS-16, the landing Falcon 9 booster entered a spin rotation due to a stalling grid fin hydraulic pump. According to Musk, the engines stabilized the spin. How is this possible? The main engines ...
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If the CRS16 booster was out of control, how did it abort to water?

The CRS-16 missions first stage, seems to have had a stuck grid fin. Apparently a hydraulic pump failed. It was spinning fairly wildly and clearly did not try to land at the pad as it was scheduled. ...
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Propellants used for different Mars landers [till 2018]

What propellants have been used by lander to land on Mars surface?
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How was the landing site decided to land InSight?

From this article The High-Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter plays an important role in evaluating candidate landing sites on Mars. HiRISE ...
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Won't the heat sensor probe interfere with the seismometer?

I've read that the Mars InSight Seismometer will be deployed before the HP3 probe. Won't the digging interfere with the seismometer? Or the shock produced will be small enough to be dissipated by the ...
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Why does the Mars InSight Lander look wet like a cardboard box that came in contact with water? [closed]

NASA has just released a photo showing a part of the InSight Mars lander wet, like a cardboard box that came in contact with water (see the picture). What is that liquid? The Instrument Deployment ...
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Why was it necessary to program InSight with an ability to land in dust storms?

If the entire event of EDL (Entry - Descent - Landing) is going to take only 7 minutes and if the command to begin could be signalled based on ground weather conditions, why was it necessary to take ...
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How do Mars spacecraft control attitude on final descent and landing?

When I watch videos of probes landing on Mars after cutting the parachutes off, they show the lander doing final orientation adjustments before touching down. The engines don't seem to have a ...
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Details about the BFR abort procedures?

What kind of emergency procedures will the BFR have during landings? I can see an abort to an alternate landing zone but what about when you have a an emergency ten seconds after engine shutdown?
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Is it possible to navigate space travel with no computer?

From launch to land could a person travel in space with only mechanical devices like a sextant? With enough experience what would be the minimum devices needed? Which vehicle currently would be easier ...
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Purging process of a rocket engine

Does spacex purge Falcon 9 engines after landing ? If so, which gas is used for purging?
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Nadir sensor for a spacecraft attempting to land

Is it possible theoretically for a sensor to detect Nadir? This could actually be of extreme value as generally spacecraft attempting to land need to maintain certain heading w.r.t Nadir as a function ...
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1answer
191 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? ...
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1answer
687 views

Can Stratolaunch land with the rocket still attached?

Is the Stratolaunch plane able to land with the rocket still attached, if a malfunction is detected – and the plane has to return without having launched its load? Is there a known emergency ...
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1answer
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Could a reentry powered monorail and flywheel make a kinetic engine for lift?

On reentry could a flywheel spin on a magnetic bearing creating a centrifugal force to keep the ship level whilst creating a plasma air pocket from the pits in the rotating heat shield? This would ...
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1answer
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Does deploying the parachute dehermetize Soyuz?

When watching the Year in Orbit documentary, one of cosmonauts points to the big bags stowed between/above the seats of Soyuz capsule, identifying them as the main and emergency parachutes. But they ...
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Is the atmosphere a positive or a negative for reusability?

Does the atmosphere provide a benefit or detriment in terms of fuel economy for rockets that take off and land back on Earth? We know that the atmosphere plays a large role in helping slow down ...
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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 ...
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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 ...
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Why can't Falcon 9 fairings touch the water?

SpaceX is spending considerable effort to catch Falcon 9 fairings into a giant net on a ship. I am aware that salt water ruins almost everything in the long run, but the fairings are a composite ...
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1answer
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What is the minimal TWR of Falcon 9 booster right before touchdown?

A big point about Falcon 9 booster landing is that they need to stick the landing on the first try; they can't just hover and adjust position because even fully throttled single Merlin engine provides ...
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1answer
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How was/Was Kalam-sat Recovered from the Ocean?

I was reading this article about Kalam-SAT and it states that: "Kalamsat fell into the sea. It will be recovered and NASA will be sending it back to us for decoding the data," [Srimathy Kesan, ...
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Will SpaceX delay launches, if the landing site weather is unacceptable?

With the initial landing attempts, it was not a big deal, twas all an experiment and they only reused Block 1-4 boosters once at best. So holding a launch because of weather at the landing site ...
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1answer
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Landing shock of Soyuz spacecraft?

Every astronaut launching on a Soyuz has a custom-made seat. The seat should prevent injuries from the very hard landing. Are there any numbers about the maximum decceleration when hitting the ground?