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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Why does the heatshield have to be on the outside?
To what extent has internal insulation been tested to deal with the heat of re-entry?
In the case of Starship, is the existing steel strong enough (to be non-ablative!), or would a different type of ...
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Why are tiles used instead of other novel solutions, for non-ablative heatshields?
Are tiles that much more cost effective as a thermal protection system?
What other novel methods have been tried? The obvious issues seem to be different thermal properties and rigidity and how to ...
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Person falling from space
A person at rest 500 km above the Earth falls straight downwards. She has a snug magical force field around her that is totally rigid and completely protects her from outside heat. The force field ...
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Did Starship Ship 25 burn up on re-entry?
SpaceX Starship Ship 25 launched and managed a successful separation from the booster and reportedly made it into space before the autonomous flight termination system activated, destroying the ...
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What is the largest object/mass that can survive entry into the earth's atmosphere from space without heating to 40 degrees C, or above?
This question is of interest because there are terrestrial organisms, such as bacterial and fungal spores, and even complex multicellular organisms, such as tardigrades, which can survive deep space ...
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Why doesn't the starship superheavy booster need heat shielding [duplicate]
Why doesn't it need heat shield while the second stage does?
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Apollo 13's plutonium RTG re-entry into the Tonga Trench: Good shootin' or good luck?
Plutonium powered RTGs are encased to survive re-entry. According to the Wikipedia article on Apollo 13
RTGs were used to power … the scientific experiments left
on the Moon by the crews of Apollo …...
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Earth re-entry from orbit by a sequence of upper-atmosphere dips to reduce kinetic energy?
There are quite a few questions on this sort of theme here, and I've also read one or two other things, like non-ballistic re-entry. So this might be a duplicate, but I don't think so.
To clarify: I'm ...
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square-cube law and TPS
Yesterday, I asked a question about the square-cube law and propellant tanks.
Do larger rockets tend to have a better mass ratio due to the square cube law?
I have a very similar question about TPS ...
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Hypersonic dynamic shift in large vs. small lifting bodies
Background:
Lifting bodies have been tested at small scales, though not during re-entry. For instance: the NASA HL10
Such Lifting-Body designs are seemingly here to stay with craft such as Dreamchaser ...
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Could you skim along the Karman line using a parafoil?
Imagine a person just wearing a spacesuit equipped with a parafoil returning from low orbit. Could they maintain altitude starting at 7.8 km/s above or along the Karman line slowly losing speed—maybe ...
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How dangerous is tossing equipment off the ISS?
On 2023 June 22, during an ISS spacewalk, Sergey Prokopyev and Dmitry Petelin "tossed overboard" three no longer needed devices, "off the back of the space station in a direction that ...
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Inflatable tank/balloon use for recovery
Hopefully this idea makes sense.
Basically if you've seen the space-truck (ROOST), you'll get where I'm going with this.
I'm wondering whether an inflatable tank/tank lining could be used to produce ...
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What kind of heating would occur during a suborbital re-entry?
What kinds of peak temperatures would a stage similar in proportions to the Space shuttle with a similar belly-first approach experience when re-entering from a low suborbital trajectory (similar to a ...
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Would the steel frame/skin of Starship be able to endure loss of a heat shield tile during reentry?
STS-27 was able survive reentry without a tile because the was over a metal component with sufficient thermal inertia to serve as a heat sink without melting.
Would the steel frame of Starship be able ...
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How did STS-27 survive reentry after losing a thermal tile?
My buddies and I have been arguing about this for a while, speculating about the upcoming Starship test.
STS-27 suffered damage on ascent that knocked off a tile & damaged hundreds more. It only ...
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Why don't SpaceX boosters belly flop?
The first F9 booster landing attempts failed because the booster broke up. After that, they began lighting the engines in the upper atmosphere to slow the booster.
It seems to me that their problem ...
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How can Starship belly flop with a full payload?
Starship had an empty weight of under 100 tons. Of this, less than 12 tons is accounted for by the engines. Starship is supposed to be able to make atmospheric entry with a 150 ton payload in the nose....
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Will there be a flame around the capsule from Stoke Space Technologies during reentery?
Stoke Space Technologies (https://www.stokespace.com/) will send fuel through the heat shield of its capsule to keep it from heating up. They actually mentioned that they are more concerned that the ...
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Design constrains for non-aerobraking re-entry vehicle?
Currently, getting from orbit to ground always involves aerobraking to shed lots of orbital velocity. This is a dangerous, stressful maneuver which also cannot be repeated with same vehicle due to the ...
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Does an inflatable heat shield have some capacity to be used for LEO Earth's atmospheric entry?
It was originally designed and tested by NASA for Mars missions.
In my case, it does not have to work 100%. Even if it survives for only 1 minute or so, during atmospheric entry - it could add some ...
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Do larger less dense objects heat less while entering the atmophere?
When a space craft enters the atmosphere, it gets hot and heat shielding is needed. Do objects with more surface area and less density heat up less then heavier, smaller objects? Could an object with ...
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What do they call “all the provisions provided during the launch campaign or atmospheric re-entry of a spacecraft“ in the context of astronautics?
I am reading an entry in a French dictionary and translating it into English. This entry is “sauvegarde.” In a general context, this term is translated as “safeguard,” “protection,” or even “...
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How much does it cost to return 1 kg from the ISS to the Earth? What are the parameters influencing this price?
I heard in a few places downmass is a limiting factor in the ISS national lab capacity. Is that true?
According to NASA's pricing plan, it actually costs more to get downmass than upmass. Why is that?
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During spacecraft reentry why is heatshield side down the most stable orientation?
During reentry, why is the orientation of the spacecraft where the heat shield side leads the vehicle the most stable?
I'm not sure how accurate KSP is, but when I reenter the atmosphere headshield ...
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What is the reason Starlink satellites took 4 days to re-enter during the accident on February 2022?
I am reviewing the incident that knocked out 39 Starlink satellites earlier this year.
As I explain in this thread, there was a modest magnetic storm on the 3rd of February, which increased ...
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Does a capsule rotate naturally during atmospheric re-entry?
If during atmospheric re-entry a capsule (with a shifted center of mass to produce lift) does not produce any rcs thrust, will the capsule naturally roll? and why?
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Has NASA used a consistent definition of "entry interface"?
The question "Orion re-entry velocity: Why is it higher than Apollo?" has an unstated but critical assumption: that re-entry is measured at the same point for both missions. The point ...
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Orion re-entry velocity: Why is it higher than Apollo?
Title says it all. I am puzzled why Orion will be traveling faster than Apollo.
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How to compute orbital decay of a cubesat?
I'd like to compute the orbital decay of a cubesat in LEO/VLEO due to atmospheric drag. Here is what I've done:
Based on the Satellite Orbital Decay Calculations document coming from the Australian ...
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Why don't we know exactly where the Chinese rocket will fall?
China has launched another Long March 5B rocket that seems liable to fall anywhere
Although the overall risk of harm to people is low—there is only a 0.5 percent chance of injury or death to a human, ...
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I'm building a CubeSat for a short 8-day mission in LEO followed by a fairly quick reentry, what range of orbits to consider?
The goal of this CubeSat mission is to demonstrate CubeSat construction, operation, and communication in Low Earth orbit for 8 days or longer.
Why the short mission time? Because the mission lacks ...
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Do we actually know what re-entry looks like?
So I was watching this video of a talk given by the creators of the game Kerbal Space Program. The video is more or less about game development, but this part (link should go right to the moment but ...
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How do we ensure that during reentry or descent of spent stages, it doesnt hit any aircraft or incoming rocket?
When a rocket is launched, stages are separated at different intervals and altitude. The lower stages usually descend immediately while upper stages and orbital platforms usually last in space a bit ...
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Commencing atmospheric re-entry
Once a decision is taken to get back home (earth), a spacecraft, I think has two options: 1 - To reduce its speed (by firing the thrusters located in the forward or something similar), so that it is ...
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How could space-manufactured goods be transported to earth surface?
In the near-to-mid future when ISRU and manufacturing in space is large enough to have an export industry back to Earth, there may be not only a significant volume of raw materials heading back to ...
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Does the debris from the re-entry of Long March core stage ever reach the surface?
It's common for SpaceX to de-orbit the second stage over the ocean (since they still have fuel for controlled re-entry,) but for the Long March core stage that is not the case.
Meteorites have hit the ...
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Could dust kicked up from the Apollo landings reach Earth intact?
According to various sources (1,2, and 3) lunar landings kick up a lot of dust at very high speeds. Is it possible that some dust was able to get fast enough to escape the moon, fall towards Earth, ...
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What does it mean when they say "switch to 32K " during the Phoenix Mars entry
In the Phoenix Mars entry video
they keep saying "Odyssey switching to 32k", "Stop of Odyssey unintelligible Data and switch to 32k",and "We ...
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Why does the Falcon 9 first stage continue to decelerate after its reentry engine burnout?
As you know, Space X streams its missions and the speed and altitude data of the vehicle is shown. After stage separation, stage one gains speed and accelerates in its decent trajectory till reentry ...
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How to design Heading Alignment Cone(HAC)?
I am trying to design a Heading Alignment Cone. Of course, the radius of the circle depends on different parameters like energy, altitude, and aerothermal characteristics of the reentry vehicle and ...
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How do I convert from one local NED frame to another?
A little bit of background in case you are interested. I am running a re-entry simulation, and I am dealing with two different reference frames. The one with the higher fidelity dynamics is in the ...
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How spontaneously can a spacecraft be deorbited [duplicate]
Currently the return of AX-1 has been rescheduled multiple days due to weather concerns in the landing area. How quickly could astronauts on the ISS evacuate to the ground if so required?
Scenarios ...
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Mystery balls! Gemini apparently had "thousands of hollow ping-pong-sized balls made of extremely thin aluminum embedded within its walls". What?
This fascinating answer says that "The Gemini capsule floated because it had thousands of hollow balls made of extremely thin aluminum, each composed of two half-spheres welded together, the size ...
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How might an "imminent Starlink reentry in your area" alerting script work?
The video below Space debris over Puerto Rico (2/7/2022) SAC seems likely to show one or more reentering Starlink satellites from the 40 "Starlost" lost to atmospheric heating due to a ...
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Did any Columbia debris continue orbiting Earth?
For reentry the Space Shuttles lowered their perigee to 28 nautical miles (52 km) above sea level. Shuttle Columbia disintegrated around 60 km altitude, and the first debris fell off as high as 70.5 ...
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Would it be feasible to decelerate a crewed vehicle from ~25 km/s only using the atmosphere of Mars (in the context of an "express transit")?
I boldly assumed it would some day be possible to accelerate a crewed vehicle from a refueling station (LEO, GEO, Moon orbit?) to ~35-40 km/s (with several stages) relative to Mars, so it would make ...
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Heatshield during re-entry of space vehicles
All the CMs for Apollo, as well as the space shuttles, basically used "Blunt body" technique for re-entry. While Apollo CMs used "ablative" type of heatshield, the space shuttles ...
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Could sheets of stacked graphene be used as part of a heat shield, since its melting point is 3000k to 5000 K
Since graphene material is the strongest manmade material, with "magical" properties, I wonder if it could be considered for use as a heat shield, since its melting point is 3000 to 5000 K ...
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Can an ISS module survive reentry?
Nasa is making plans to de-orbit the ISS safely over the pacific ocean, this eventually leads to the question of whether or not an ISS module can survive reentry (survive meaning it is recognizable ...
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