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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100 views

What Earth satellite remained in orbit the longest before reentering?

@BillGray's excellent answer in September 2018 mentions that the Soviet magnetospheric research satellite 1977-093A (NORAD 10370) was expected to reenter the atmosphere in 2019 due to effects ...
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SpaceX Dragon Maximum Return Payload

For one of my university courses, we were asked to assess the viability of an asteroid exploitation mission. Assuming that we can somehow mine and refine the material (platinum in this case), we still ...
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How much is a typical reentry vehicle decelerated by heatshield ablation?

Most spacecraft (or parts thereof) intended to survive atmospheric (re-)entry use an ablative heatshield, which, when exposed to the strong aerodynamic heating of (re-)entry, gradually ablates away, ...
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Hypersonic Inflatable Aerodynamic Decelerator and skip-entry to Mars

Has NASA studied whether the Hypersonic Inflatable Aerodynamic Decelerator could allow for a skip-entry*, or anything other than direct entry to Mars, to aid in a craft's deceleration? *Skip-entry or ...
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Is it harder to enter an atmosphere perpendicular or at an angle

I've heard that because Earth's atmosphere is so thick that some spacecraft can 'bounce' off the atmosphere if they don't enter at the correct angle. This leads me to believe that shallower angles ...
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Galileo Probe Altitude Data

I was reading about the Galileo Probe, but suddenly my imagination struck an obstacle. The probe was slowed from its arrival speed of about 47 kilometers per second to subsonic speed in less than ...
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490 views

How did the Corona (Key Hole) satellites film canisters deorbit?

The Corona Photographic Surveillance satellites transferred photos back to Earth by releasing a canister with the film, which would deorbit, re-enter, release a parachute and then a plane would ...
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Apollo CM heat shield burnt pattern around RCS thrusters

Looking through photos of Apollo CM capsules after reentry, I was trying to have a feel for how the heat was distributed on the sides of the capsule. By the look of surviving patches of Mylar tape ...
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Reentry without pressure suits in Apollo: was there a formal risk assesment?

In Apollo 11 Flight Journal the following is stated: The crew will make re-entry without suits or helmets on. Although this was a controversial decision on the first Apollo flight, Apollo 7, when ...
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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 ...
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How was the Vostok capsule stabilized for spin during descent, after the equipment/maneuvering module had detached?

The spherical Vostok capsule separated from the rest of the spacecraft when beginning descent. The center of gravity was "below" the cosmonaut's couch, so the capsule didn't tumble. But what prevented ...
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How do the chutes stay separate? [duplicate]

In the below picture the parachutes are spread out, but ordinarily drag would pull all the chutes to the same position directly behind the capsule. How is this spread achieved?
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Could SpaceX's Starship's landing and restart process work on Titan?

Gravity on Saturn's moon Titan is much weaker and the atmosphere is far denser than either Earth's or Mars's, which Starship seems to have been designed for. Could an unmanned starship do an Earth-...
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Is there such thing as plasma (from reentry) creating lift?

The following was claimed on the aviation site: In 1981, after years of development and testing, Columbia made its maiden voyage into orbit. Unexpectedly, on re-entry, the nose pitched up much ...
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132 views

What forces a spacecraft, returning from Earth orbit, to synchronize with Earth spin?

This seems like a banal question, but the more I think about it, the less I understand the mechanics of it. Does the progressively denser atmosphere pick up the spacecraft and carries it along the ...
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What is the principle behind using a moment reference center to compute the moments acting on a spacecraft re-entering a planet's atmosphere?

I have seen the term "moment reference center" and from a general perspective, I understand that it is a point arbitrarily chosen to calculate moments acting on a entry vehicle (I am reading a lot on ...
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Help Finding A Book

I am trying to find the book that contains the following chapter: https://www.faa.gov/about/office_org/headquarters_offices/avs/offices/aam/cami/library/online_libraries/aerospace_medicine/tutorial/...
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What would be the cost of construction of space capsule (re- entry modules)

I would like what would be the range of costs for building a space capsule , ranging from the Apollo times to the new Boeing Starliner.
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What materials should I use to make a suborbital amateur rocket and where can I buy them? [closed]

I’m trying to make a suborbital rocket to get some pictures of the Earth but I’m not sure what material’s to use and where to get them. I’ve been thinking of titanium for the shell but I’m not sure ...
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1answer
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Expansive ablative heat shield

Are there studies about using expansive foam such as polyurethane, so that it provides high volume & high cross section heatshielding, instead of inflatable ones, or in combination with inflatable ...
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Minimal heating a realistic reentry vehicle could achieve?

In this question, I asked whether it would be possible to make a reentry vehicle that could slow down from orbit and glide to the ground entirely passively. The answers and comments point out several ...
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1answer
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Why does the Apollo reentry trajectory show a few climbs?

In this answer the following graph is displayed: It shows two slight increases in altitude (after 1st peak g and at the end of the blackout). For me, it looks like zoom climbs (trading kinetic ...
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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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Are there examples of cargo being damaged during re-entry?

Are there examples of items being brought to or returned to Earth that were damaged in the re-entry process? For example, lunar samples during Apollo, or something being returned in the Shuttle ...
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Did the heat shield of the Vostok 1 capsule ablate during reentry?

This Wikipedia article (in german) has some information about the heat shield of Vostok 1. The heat shield was made from asbestos, its thickness was increased from 3 cm to up to 18 cm. The weight of ...
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Why don't the hottest temperatures of a re-entering spacecraft occur near the “bottom”?

The paintings of the Apollo command module and space shuttle below portray the heating effects of re-entry. The whitest parts of the spacecraft get the hottest, with cooler parts in red and darker ...
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What is the longest manned re-entry from Low Earth Orbit ever recorded?

What is the record for the longest amount of time that a manned spacecraft has taken to re-enter from low Earth orbit (LEO)? I would prefer the duration between the beginning of the re-entry burn ...
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1answer
194 views

How do I calculate re-entry velocity when decaying from a circular orbit?

I am trying to find the velocity of an object during re-entry so that I can calculate the peak heat flux but I'm a bit stuck. I know how to find the velocity of the original, circular orbit (300km) ...
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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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At what altitude does a spacecraft slow down?

So as far as i understand at 100km atmosphere exists although very faint. Could someone aproximate the speed of a sphere at 50km altitude after re-entry from a high orbit? It might sound as a wierd ...
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Two stage reentry from Moon/Mars

There are a number of questions addressing the desirability and/or feasibility of a slower reentry from Earth orbit in order to reduce thermal load. At least most of them run into the problem that ...
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Why didn't the Space Shuttle bounce back into space as many times as possible so as to lose a lot of kinetic energy up there?

From this video, I got know that Space Shuttle did reentry around 5000 miles away from landing site. It's angle of attack is maintained around 40 degrees during re-entry. If it is more than that, it ...
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What is the point in which metal turns white hot during launch or reentry called?

This is a slow motion film of the Sprint missle. There is a point where to skin goes white hot like a light switch. What is that called? What metal gets white hot while keeping its shape?
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Do owners of reentering spacecraft notify the countries' whose airspace they are likely to violate and seek permission?

@PearsonArtPhoto's answer contemplates: Any object that is below 100 km now is considered an aircraft, and technically needs the permission of the country over which it is flying to enter that air ...
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Why not increase contact surface when reentering the atmosphere?

If a craft were to increase the surface area where contact is made with air during reentry, I imagine the heat quantity per area unit would decrease, making the use of (heavy) heat shields less of a ...
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how is the g-load for an atmospheric re-entry vehicle measured? and why is it relevant?

Out of curiosity, I always heard about g-loads regarding entry vehicles and in aviation, I understand the relevance of the concept when humans are involved, and for unmanned missions I gather that due ...
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Sharp nose or Blunt nose vehicle for higher rentry speeds?

Hypersonic Technology Vehicle 2 (HTV-2) is a crewless, experimental hypersonic glide vehicle rocket glider developed as part of the DARPA Falcon Project capable of flying at 13,000 mph (Mach 17.53, 21,...
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What is the orbit and expected lifetime of Crew Dragon trunk?

Per the timeline mentioned in the webcast the Crew Dragon separated from its trunk before the deorbit burn. I suppose that happens so clean separation can be confirmed before committing to deorbit as ...
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Nose cone of Dragon 2 closes only after deorbit burn

The Dragon v2 capsule opens its nose cone right after it separated from the Falcon's second stage. It is then open for the whole flight until after the deorbit burn. So there appears to be a good ...
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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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3answers
610 views

How do orbital spacecraft calculate reentry?

For a given spacecraft, in a given LEO orbit, assuming you have all the required data, how do you choose the needed burnout speed and timing (or position in orbit), in order to reach a certain point ...
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Pressure effect during atmospheric entry

Maybe this question has a very obvious answer (I'm no aero engineer though), but I'll appreciate the clarification! So, I was reading an old nasa paper that indicates that the dynamic pressure for ...
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2answers
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Titan vs Mars for colonization

This question is along the same vein as Venus vs Mars for colonization but without the person at the table. Is Mars better than Titan which to me seems a more realistic option for colonization? With ...
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1answer
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Will SpaceX vehicles orbit Mars before they enter the atmosphere?

When SpaceX starts sending vehicles to Mars, how will they handle landing on Mars? Will the Starship (Upper Stage, transit vehicle) slow down enough to capture into orbit of Mars before entering the ...
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1answer
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What is crossrange and downrange for an entry vehicle?

I have been searching the terms online but still can't get a more intuitive understanding. If you could refer me to some website, book or if you could offer me an explanation I would really appreciate ...
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1answer
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Heat Shielding Material for Reusable Craft

I'm a bit new to all this and have a quick question about heat shielding. My research tells me that for reusable craft (i.e. Space Shuttles) they used to use a plastic-based shields that would burn ...
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The aerodynamic stability of the truncated cone shape

Can someone explicate the stability of the truncated cone shape of the reentry vehicle of a spaceship when moving in the atmosphere with its bottom facing forward? It seems counterintuitive that it ...
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1answer
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Is a ballistic blimp entry possible on this way?

Could the entry of Mars with balloons work by inflating to equalize with the atmospheric air pressure, while establishing buoyancy before meeting the ground? Would a balloon pop if dropped from space?...
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Could a spacecraft produce lift using sublimating material?

Following this question, could a spacecraft approaching upper atmosphere from very low circular Earth orbit, produce lift to soar propulsively, bleeding speed at constant apoapsis, by sublimating ...
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Could ablative material sublimation slow down a spacecraft?

Thought experiment illustrated below: Suppose a weird spacecraft entering Earth's atmosphere from low Earth orbit, payload first. Behind it there is an inverted nozzle shaped structure, attached with ...