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Questions tagged [reentry]

Questions related to the movement of human-made objects as they enter atmosphere of Earth or other planetary bodies with atmospheres from space after being successfully launched.

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How do the dynamic pressure evolves during reentry?

During launcher ascent, dynamic pressure evolution is describe in this answer for the Saturn V. I suppose this is comparable from one launcher to another. Given the protections designed for reentry, ...
6
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1answer
188 views

How does falcon-9 engine survive while re-entry burn without chilling ?

I've often seen that in launch sequence, "engine chilldown". I've learnt that chilling is done to avoid thermal cracking in plumbing lines and also to avoid cavitation. While re-entry, do they ...
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0answers
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What are the three peaks in this Apollo reentry heating plot?

The question Challenging Karman line from above includes the following plots and cites an answer in Quora by Robert Frost, Instructor and Flight Controller at NASA who has provided many authoritative ...
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2answers
183 views

Drawbacks and advantages of two slidable & rotatable control surfaces for BFS sized spaceships

BFS (SpaceX's Big Falcon Spaceship) is in development and has seen between 2016 and 2018 three major design modifications. January 2018 I asked here how BFS planned to manoever during aerobraking. ...
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2answers
201 views

Why does in-flight mission abort often ends in ballistic high-$g$ reentry?

I am seeing a lot of references to the “ballistic reentry” mode of the crew return vehicle in relation to the abort during the powered ascent stage. In partiulat, the recent crewed Soyuz MS-10 abort ...
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1answer
109 views

What is the likely plan to deorbit the ISS given its size and shape?

The ISS is nearing its final years and this question spurred me to ask a follow up. Let's say that the various countries grab whatever equipment/modules they provided in assembly and the ISS is ...
3
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1answer
138 views

Satellite retrieval, fix and deploy possible remotely?

Is there any satellites that are designed to come back to Earth for repairs or upgrades and then be deployed again? Would there be any benefits to creating a capsule or inflatable heat shield to go on ...
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2answers
5k views

What eliminates the velocity when occupants return from ISS to earth, and how much?

The ISS has an orbital velocity of ~28000 km/h; the velocity $v$ relative to the landing site of the descent module is probably even higher than that most of the time. Once the occupants have landed, ...
6
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1answer
423 views

Could I use a satellite as a vehicle for delivering airborne leaflets?

Assuming I have a satellite in a decaying orbit, could I gently release leaflets from my satellite so they were on a near-identical sub-orbital trajectory and have them touch-down safely on the ground ...
4
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1answer
116 views

What does “Poisson's formula” refer to in this calculation?

I am not entirely sure if this question belongs to this forum, but I don't know where else to ask. I am following a Rocket Propulsion course. There is a section concerned with the Velocity ...
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0answers
76 views

Would the right shape dimple heat sheild create more wake? [closed]

In this question: Would a dimpled heat shield reduce heat transfer during reentry? the answer says no it would not help more or less. My new question is would reverse dimples or bumps or a ring/s ...
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4answers
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Why can't you just parachute down right from orbit?

This will surely seem, at least at first sight, a completely stupid idea, seeing the usual “space isn't high away, it's fast away”, and that the heat shields which actually are used need to withstand ...
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5answers
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Have Air-breathing Engines ever been used on a reentry vehicle, could they be?

For the purpose of this question I would like to assume there is no risk of life for the astronauts, or that the design would only be used for delivery of a non-ethically-sensitive payload. Looking at ...
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2answers
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Why didn’t the Spacecraft used for the Apollo 11 mission melt in the Earth’s Atmosphere?

My brother has recently been converted to a Flat Earther and is convinced that something that proves his theory is the moon landings being faked by NASA. I have managed to counter argue the majority ...
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0answers
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Nature of “the silky black 'highly flame-resistant felt'” on Block 5 Falcon 9's, and its intended functions?

The Teslarati article SpaceX Falcon 9 Block 5 rocket’s drone ship return captured in stunning detail [gallery] and accompanying photo spread shows many interesting details of "SpaceX’s first West ...
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0answers
354 views

Have spacecraft ever dipped below the Karman line and then safely continued spaceflight?

The item in Science Alert's A Harvard Astrophysicist Says Outer Space Is Actually Closer Than We Think (see also Science; Outer space may have just gotten a bit closer) talks about the recent Acta ...
5
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1answer
192 views

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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6answers
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Dangle a cable down to earth - fundamental Physics question

If I had the material that had the tensile strength, would it be possible to have it dangle from the lowest most practically possible geostationary object down into the atmosphere? Would it not ...
4
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1answer
333 views

Can a reentry be done slowly?

The usual approach to reentry is fast and hot. There's a lot of energy to be lost, and doing it quickly has some advantages: You can dump energy into hypersonic air, and then leave that heat behind ...
2
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0answers
71 views

How would the space shuttle fare without payload doors? [duplicate]

If the space shuttle had the doors locked open, blown off, or otherwise unable to close, would it be able to re-enter and land somewhat intact? Was there any procedures in place on the off chance this ...
5
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1answer
93 views

Would landing on mars during a storm considerably increase atmospheric drag?

Any chance we could harvest all those dust particles for an significant improvement in aero-breaking capabilities or would it destroy most heat-shields?
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2answers
146 views

With what attitude does Soyuz reenter, and in what way might this angled pattern on Exp. 53's return a result of attitude?

The BBC article Soyuz space capsule brings ISS crew back after five month mission describes the return of ISS Expedition 55's "Russian Anton Shkaplerov, American Scott Tingle and Japan's Norishige ...
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0answers
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Looking for atmospheric density models of various planets and moons

Looking for atmospheric density models of various planets and moons, any sort of data/resources/database of this information would be extremely useful as I am working on recreating these models for ...
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2answers
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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 ...
12
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1answer
769 views

Is this smoke from Expedition 53 returning Soyuz capsule?

I was clicking through YouTubes and came across the NASA Video ISS Expedition 53 Landing in Kazakhstan (also here). I don't recall seeing such prominent and continuous smoke from returning Soyuz ...
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1answer
247 views

How to calculate the stagnation temperature at the tip of the nose of a reentry module?

A re-entry module flies with Mach 10 at an ambient temperature of –27°C with. CP = 840 J/kg-K, gas constant R = 140 J/kg-K. What is the stagnation temperature at the tip of the nose of the re-entry ...
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2answers
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Is there real footage of Tiangong 1 reentry?

There are a couple of videos on the net showing some reentries and claiming them to be Tiangong 1. Is any of them authentic? I could not find any footage on the websites of the major space agencies (...
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2answers
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Why are Tiangong-1's Apogee and Perigee Graphs Wobbly?

The apogee and perigee graph of the Tiangong-1 space station, about to re-enter and break up Real Soon Now, is depicted in this graph (source: Wikipedia): Why are the graphs wobbly? Is it because the ...
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1answer
2k views

Why is there a need for getting rid of ISS trash using the empty ATV and similar vehicles

Why is trash from the ISS sent down in some of the cargo vehicles. Would it not make more sense to dump it overboard in the downward + retrograde direction (as described here) and use reusable cargo ...
6
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2answers
234 views

How are impact probability maps rigorously calculated?

This is one example of an impact probability map. It was posted in this question and is from Aerospace Corporation. But My question is about the process, not this particular map, although it is a good ...
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0answers
56 views

Nano spacecraft reentry

Suppose if one designs a Small size reentry capsule. What will be the typical deacceleration achieved by atmosphere. More precisely, what is the relationship of the size and drag by atmosphere. I am ...
2
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1answer
454 views

Would a balloon pop if dropped from space?

Could a inflated party balloon be dropped from space and not make it to the the ground intact although flat and deflated from air pressure? or A sturdy balloon is inflated with helium/oxygen to ...
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2answers
2k views

Tiangong-1 reentry impact place probabilities

Following all the news concerning Tiangong-1, I have seen the following plot made by the Aerospace Corporation where Blue area: null probability of impact Yellow area: high probability of impact ...
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2answers
494 views

How long does trash jettisoned by hand from the ISS fall before burning up on reentry?

NASA proposed a policy for the jettison of trash from the ISS space station. This article notes that a recent ISS space station spacewalk by Russian cosmonauts involved one man jettisoning by hand a ...
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2answers
253 views

How are old satellites removed from orbit? [duplicate]

Once the satellite is nonfunctional how are they removed from orbit?
3
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1answer
232 views

How stable is an orbit of 335.9 km?

Spacex has recently begun deployment of its satellite constellation that will provide internet services. In their initial filings with the FCC they propose that they may have over 7,000 VLEO (very low ...
4
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1answer
268 views

Which crewed spacecraft provides the gentlest decent and/or landing?

Landing with a Soyuz capsule is often compared to being in a car accident1, it's pretty violent on touch-down. On the other hand, I imagine the Space Shuttle's touch-down to be a little like a rough ...
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1answer
408 views

Why does NASA still use film cameras?

According to this video, NASA still operates some cameras for tracking rocket launches that use film: According to NASA, they even have some film cameras placed around their launch site loaded ...
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0answers
304 views

What will the heat shield on the BFS be made of

Musk has stated that the BFS will need a heat shield capable of reentering the atmosphere from interplanetary trajectories. So I take it the ship will come in directly from the transfer trajectory and ...
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0answers
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What happens with re-entry at different angles?

I was reading the article on J002E3, and it mentions that most other S-IVB have entered the atmosphere and mostly burned until reduced to relatively small pieces. They did, however, enter the ...
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2answers
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What aspects of reentry heating 'scale as the 8th power'?

Elon Musk just commented in the post Falcon Heavy Test Flight press conference that reentering at interplanetary velocities means dealing with 'some of the heating things that scale to the 8th power'. ...
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1answer
287 views

How do re-usable boosters handle re-entry damage? [duplicate]

Watching Falcon Heavy's side boosters land, I was amazed that they could withstand the stresses of re-entry yet still fire again for a (relatively) slow, smooth landing. I see there are heat shields ...
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3answers
399 views

Soyuz has a Space Periscope?

The image Photo ID: ISS049-E-003166 can be found in Flikr and Wikimedia Commons as well as in Spaceflight Now. There is a long (perhaps 1 meter?) green structure that is sticking out from the side of ...
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1answer
265 views

Is it possible to develop a small orbital rocket, like RocketLab's Electron, for a weapons delivery system?

Now that Rocket Labs has proven that orbit is well within the range of small nations and medium-sized companies, I have to wonder about the strategic implications. AFAIK the Electron rocket has an ...
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2answers
396 views

How will BFS maneuver during aerobraking?

Pictures of SpaceX's "Big Falcon Spaceship" (BFS) delta wing don't seem to show presence of any aerodynamic control surfaces. How will it's attitude be controlled when encountering the atmosphere? To ...
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1answer
325 views

For a given amount of fuel, what is the best de-orbit profile for the ISS?

Reading this question, what is the best way to make sure most of ISS (or any other large object planned to be destroyed in the atmosphere) will burn and break into relatively small pieces in the ...
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0answers
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Atmospheric Entry Vehicle: Wind frame representation and Visualization

I am looking at entry dynamics for a convex blunt aeroshell. We use Heading angle, bank angle and flight path angle for description of attitude from local horizon axes system. While it is sufficiently ...
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2answers
120 views

Atmospheric drag vs. atmospheric heating. Which occurs first?

If I was in a circular 10km orbit (theoretical) around Earth, what will occur earlier? Will I burn up in atmosphere or be stopped by atmospheric drag?
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1answer
185 views

Why a donut-shaped balloon decelerator in the Aldrin-Purdue proposed Mars lander descent?

I saw this project linked within this excellent answer. Why is this proposed balloon (assisting in deceleration of the proposed Martian atmosphere entry) donut-shaped? Are there aerodynamic, stability ...
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1answer
204 views

Would a dimpled heat shield reduce heat transfer during reentry?

Would a large ceramic golfball absorb less heat on reentry than a standard sphere? From aerospaceweb.org: The difference in the flowfields around a smooth sphere and a rough, or dimpled, sphere ...