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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3
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1answer
69 views

Delta-v for landing on the moon

I'm doing a few calculations to understand how to go from the Earth to the Moon. I used an elliptical (Hohmann Transfer) orbit to go from LEO to a circular Moon's orbit performing two $\Delta v$ (...
4
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1answer
77 views

What was the radius of Insight's disruption of Martian regolith?

A NASA animation depicts the Martian regolith being disturbed by the retrorockets of the Insight spacecraft while landing. Did NASA estimate the radius of the disruption, or was there any indication ...
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Why have JPL martian rovers stopped using airbags and started using skycranes? [duplicate]

Pathfinder and the Mars Exploration Rovers used airbags to kill their terminal velocity. The Curiosity and Mars 2020 rovers have or will use skycranes. Why have JPL started using propulsive terminal ...
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1answer
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How did the Mars Exploration Rovers (Spirit & Opportunity) land upright? [duplicate]

In every animation depicting the landing of the MERs, the tetrahedral airbag compartment is bouncing & tumbling after surface contact. How did Spirit & Oppy ensure they would come to rest ...
5
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1answer
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Landing legs problem with Falcon 9 Block 5 / Starlink 3 mission

Is this a late landing burn problem? it seems that the engine touch the OCISLY ground as the landing legs flex. Landing occurs at about T+0:08:20
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2answers
256 views

What is the “floating dust” seen in the Starliner test landing colour footage?

The first Starliner landing was in the very early morning. The live coverage was only able to show infrared pictures of the descent, however NASA's documentation of the event includes a colour video ...
2
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1answer
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Controlling suicide burn landing location in a python simulation?

I recently asked a question in stackoverflow about Simulation of suicide burn in openai-gym's LunarLander. Sadly most of my assumptions about suicide burn implementaion were wrong but the answer given ...
5
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1answer
524 views

How close to Guam did China's recent Long March 5's first stage fall?

Jonathan McDowell'sTweet and Tweet say Two objects cataloged from the CZ-5 launch: 180 x 67690 km x 19.4 deg, and 203 x 73395 km x 19.4 deg. One is the SJ-20 comms satellite and the other is the ...
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1answer
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Did any of the Space Shuttles land through rain or rainclouds?

My web research resulted in figuring out that launching Space Shuttles in rain, apart from lightning, wind and turbulence related problems, wasn't permitted due to: brittleness of the heat shield ...
4
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1answer
120 views

Single Engine versus Multiple Engines for Moon Landing

Does it really make any huge difference in the amount of lunar dust disturbed or raised during a Moon landing while using a single-engine compared to using multiple engines? I do not think there ...
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3answers
427 views

Why are these Soyuz Astronauts/Cosmonauts wearing sun glasses and a blanket after landing?

Why are these Soyuz Astronauts/Cosmonauts wearing sunglasses? Is there any scientific reason for this? (Please don't say they want to look cool) I have not seen Shuttle Astronauts wearing sunglasses ...
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4answers
341 views

Why don't we use sound suppression system when rocket lands propulsively?

We know that the sound suppression system (water deluge system) is used to protect the launch vehicle from the acoustic energy produced by the engines. For most of the expendable launch vehicles, it ...
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0answers
46 views

Can we use magnetic devices to anchor to asteroids?

One of the challenges about missions to asteroids is staying attached to them when you land. Many asteroids are described as nickel/iron, and we know that both nickel and iron have magnetic ...
5
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1answer
189 views

What kept Vostok/Voskhod from tipping or rolling upon landing?

Considering that the reentry capsule of Vostok and Voskhod were spherical, what kept them from rolling or tipping after landing? Soyuz has a flatter bottom, so I would expect this to be less of an ...
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0answers
199 views

Why will Russia start arming cosmonauts again?

The Phys.org article Russia to give cosmonauts guns to fend off animals on landing says: Cosmonauts have been unarmed for more than a decade but Roscosmos agency head Dmitry Rogozin said it was ...
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1answer
106 views

What measures were taken to clear wildlife from the Shuttle Landing Facility?

What was done to prevent or remove wildlife such as alligators and birds from the runway at Kennedy Space Center, so the Shuttle could land safely?
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2answers
85 views

Why a rover bumps after landing on Mars?

Sometime ago I was watching a video which showed that when a rover lands on mars surface it will keep bumping on mars surface like a ball until it gets rid of stored energy and then it becomes static. ...
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8answers
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Is there any way to land a rover on the Moon without using any thrusters?

Is there any way to land a rover on the moon without using any thruster, with the help of Thermocol, Cotton, Bubble wrap or any other packaging material, like we can receive from online shop?
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0answers
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Delta-v cost of longitudinal plane change correction?

In a recent question, the slow drift of a landing site on a rotating body relative to an orbiter came up. This would sometimes require a plane change correction when one desires to recover the ...
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5answers
6k views

Why were contact sensors put on three of the Lunar Module's four legs? Did they ever bend and stick out sideways?

In the video Brian Eno on Apollo starting at 08:37 there is Apollo-era movie footage of a lunar module taken from the command module as it prepares for descent ...
21
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2answers
4k views

How far off did Apollo 11 land?

Armstrong wasn't able to land exactly in the designated landing location, as far as I know it was too rocky. So he had to fly a bit farther to find a suitable spot. But how much farther from the ...
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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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3answers
5k views

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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1answer
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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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1answer
260 views

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 ...
3
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2answers
306 views

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
470 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 ...
5
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2answers
313 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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1answer
211 views

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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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
84 views

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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246 views

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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3answers
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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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2answers
238 views

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 ...
4
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1answer
185 views

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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3answers
1k views

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 ...
4
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1answer
139 views

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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1answer
176 views

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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2answers
306 views

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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2answers
1k views

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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0answers
73 views

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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2answers
2k views

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 ...
4
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0answers
107 views

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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0answers
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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 ...
4
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1answer
252 views

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. ...
4
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1answer
339 views

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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5answers
5k views

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 ...
5
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2answers
277 views

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. ...
4
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2answers
118 views

Propellants used for different Mars landers [till 2018]

What propellants have been used by lander to land on Mars surface?

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