Questions tagged [thermal]
How heat affects spacecraft and space missions, or materials and methods to deal with heat.
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Could a planet only support underwater life?
I imagine the surface of Europa to be a barren atmospheric wasteland. But under the ice, acting as insulation, and where water meets soil, would it be warmer from geothermic heat to better support ...
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Does increased thermal emissivity decrease the effectiveness of a solar sail?
I am aware that increased emissivity in solar sails aids with heat reduction, however, I have done some research and found that the emissivity decreases the trajectory of the solar sail through the ...
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Simulating the thermal heating of a nose cone exiting an atmosphere
I have a simulation that describes a vehicle traveling at very high speeds (near or even above orbital) up out of the atmosphere and into space. I'd like to chart the rate of heating ($\dot{q}_{conv}$ ...
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How many heat shield tiles are installed on Starship and what is their total volume roughly?
If paired with tile density information, this total volume information would be useful for estimating how much more mass Starship could lift in a non-reusable configuration. If also paired with heat ...
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Has any vehicle prior to Starship's IFT3 "taken a selfie" during reentry?
I'm curious about images (or videos) that a) Include both a portion of the vehicle and its re-entry plasma wake, and b) That were taken at near-orbital (high-hypersonic) velocities or greater.
I ...
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What is the white felt-like material between the heat shield tiles and stainless steel skin of Starship likely to be?
I suspect that the white padding material between the tile and the stainless steel skin might be [Nomex Felt][1], but I don't really know. Nomex was used on the Space Shuttle.
Flame-Resistant Felt - ...
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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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Typical external temperature profile for a LEO satellite
I bumped into a question regarding LEO orbit.
Is an external temperature profile available in literature as a first approximation for thermal analysis? I bumped into articles mentioning that the ...
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square-cube law and thermal protection tiles (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 ...
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Maximum and minimum surface temperatures of a satellite in GEO?
Just as the title, how could one find out, or simply estimate the maximum and minimum likely surface temperatures of a satellite orbiting in GEO.
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Why aren't the radiators on the ISS straight?
The radiators look like a highly stretched paper accordion. Is it just because of how they decomposed, or is there a deeper reason?
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Why is insulation used in spacecraft thermal control?
The temperature of spaceships can range from -126° C to 149° C. Wouldn't it be better for the spaceship envelope to have as high a thermal conductivity as possible to even out the temperatures (the ...
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How to get the reduction in Heat Flux due to Barbecue Roll on Spacecraft?
As we know, to keep the surface of the spacecraft relatively cool, we spin the spacecraft so that not just one side of the spacecraft is heated.
Due to this what is the effective Heat Flux encountered ...
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What was the coolant that leaked out of the Soyuz?
What exactly is the coolant used in the Soyuz external thermal loop, the one that just leaked out of a Soyuz docked to the ISS?
I checked the Soyuz Crew Operations Manual but it just calls it the &...
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How can you calculate the pressure that a liquid develops when freezing in a pipe?
My current understanding is that in addition to the reasons pointed out in the answer to this question here, another reason for choosing
ammonia in the space station external coolant loops is that the ...
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Good solar absorptivity and infrared emissivity values for non-anodized machined aluminum
Existing sources that I'm looking at show a wide range of possible absorptivity/emissivity values for aluminum:
http://www.solarmirror.com/fom/fom-serve/cache/43.html
https://www.thermoworks.com/...
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Why is the sunny side of JWST's sunshield purple and covered with silicon?
After about 08:52 in Destin's Smarter Every Day's Why Are there Holes in the James Webb Sunshield? (Explained by My Dad) - Smarter Every Day 270 (linked below) ...
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Is a Raptor 2's thermal output really comparable to that of a nuclear power plant?
After about 01:10:10 in the 2022-02-10 SpaceX Starship Update part of Musks answer to Tim Dodd's question about Raptor 2 development:
The only remaining issue that ...
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How brightly does Venus's hot surface glow at night? Could you see it? Could you see well enough to walk around?
NASA's Parker Solar Probe Captures its First Images of Venus' Surface in Visible Light, Confirmed links to the new Geophysical Research Letter Parker Solar Probe Imaging of the Night Side of Venus.
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First use of spacecraft thermal control louvers, doors, pinwheels, or other things that physically actuate either passively or actively?
Below are some examples of
Question: What was the first use of spacecraft thermal control louvers, doors, pinwheels, or other things that physically actuate either passively or actively?
From this ...
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Why does JWST need "a carefully designed series of oscillations" to avoid overheating during the 2nd stage burn? Why not rotate "rotisserie style"?
The Northrop Grumman video James Webb Space Telescope Launch and Deployment describes the trajectory from launch to orbital insertion and illustrates several key maneuvers and incremental steps in the ...
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Why is the hot side of the James Webb Space Telescope expected to be 85 C?
According to multiple sources, the heat shield on JWST is expected to exceed 85 °C. The average temperature of the earth is only 15 °C, so this is about 70 °C higher at roughly the same distance from ...
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Long lived solar powered rovers without radioisotope heater units (like Zhurong), for use beyond Mars
The Yutu rovers use RHUs to stay warm and survive the two week long lunar nights, every other rover uses nuclear material as well (except Sojourner), but the Zhurong rover uses a novel storage-heating ...
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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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Where was the water buildup on Cassini's narrow-angle camera system? Did it have to remain heated continuously?
Writing this answer led me to Wikipedia's Cassini; launch and cruise phase (1997-2003) which includes the following entries
0 May 2001 – During the coast phase between Jupiter and Saturn, it was ...
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How does ECOSTRESS measure both temperature and emissivity of the Earth's surface simultaneously? (Science package aboard the ISS)
The This Week at NASA video A U.S. Commercial Spacecraft Departs the Space Station on This Week @NASA – July 2, 2021 includes the following quote:
Data from NASA’s Ecosystem Spaceborne Thermal ...
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Where exactly are the Apollo space suit sublimators venting steam into space? is there a photo of an astronaut in space that shows the opening?
This excellent answer to How have space suits dissipated the heat removed from astronauts? shows a diagram including the sublimator unit in the red square where the phase transition of water from ...
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Is Geothermal Cooling on Venus Possible?
Would geothermal type cooling be possible for a stationary base on the surface of Venus?
Would the subsoil temperature of Venus hotter or cooler than the atmospheric temperature? (464C / 867F average ...
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spacecraft thermal dataset
For a high-school academic project, I would like to plot a graph of change in satellite's temperature over time.
Thus, (I think), I'm looking for real-time temperature data of sort of any (preferably ...
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Ablative heat shield and conservation of energy, how much does ablated matter in fact "carry away" versus re-radiate the absorbed heat?
I saw
Most heat shields ablate, that is they sacrifice material to carry heat away...
in a comment under this answer and started writing:
I think that shields ablate to produce a layer of complex ...
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What kind of insulation is used in the Ingenuity helicopter?
A press release from NASA today states
“This is the first time that Ingenuity has been on its own on the
surface of Mars,” said MiMi Aung, Ingenuity project manager at NASA’s
Jet Propulsion ...
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How are the electronic circuits in interplanetary missions protected from extremely low temperatures?
In an interplanetary mission, a spaceship travels through deep space, where the temperature is almost zero degrees Kelvin, and it is likely that its electronic circuits get permanently damaged. How ...
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How cold do Curiosity's & Perseverance's appendages get at night with all those sensitive cameras and lasers?
cropped from PIA19920: Curiosity Self-Portrait at 'Big Sky' Drilling Site
MastCam-Z, ChemCam/SuperCam and MAHLI are optical systems and ChemCam includes a telescope and a pulsed laser, but the ...
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Has anyone developed a reliable deep space battery that doesn't need to be kept warm?
Has anyone developed a reliable battery for use in cold deep space applications? Something that doesn't need to be kept warm?
For exampe lithium batteries certainly has its constraints due to the ...
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How to calculate the thermal energy received by a satellite at a distance from the Earth?
I need to find the thermal energy received by a satellite in LEO from the Earth, on the night side.
The thermal energy received from the Sun by a satellite is easy to calculate, because the Sun is a ...
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Are there fluid disconnects that sever just before the Curiosity or Perseverance rovers separate from their cruise stages or landers?
In this comment under an answer to Heating Perseverance components prior to deployment I wrote:
I think (but can not find a source yet) that there is even a loop of "hot water plumbing" ...
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Is Perseverance's heat shield's thickness radially symmetric?
I came across this video1 about the Mars 2020 Perseverance rover mission, especially the atmospheric entry phase.
It says between about 03:50 and ...
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Likely explanation for the bottom of the SLS rocket being covered with reflective silver "muffler" tape?
NASA.gov's First Artemis Rocket Stage Moved onto NASA Barge Ahead of Green Run contains a high resolution image of the rocket. The bottom end of the rocket's cylindrical shape is closed flat and ...
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Why are some rockets painted black? [duplicate]
Why are Rocket Lab's and other rockets painted Black? Shouldn't they be painted white to reflect most light and therefore absorb less heat from sunlight?
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Do aeroshells really get hotter than the surface of the sun?
This answer to How to design heatshield bluntness? says:
Curiosity reentry dumped about 98% of its entry energy into the atmosphere, the aeroshell can still get to be temps greater than the surface ...
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Where does a Falcon-9 get the hottest during launch, and how hot does it get? (aerodynamic heating)
We know there is a Max-Q point1 during a launch, have an approximate altitude, equations for it's pressure value and suspect it lies very near the apex of a rocket's nose.
But is there a "Max-T&...
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Why exactly does Curiosity's RTG make more electricity on cold days?
There is a fascinating factoid in this answer to MMRTG- thermal and electrical output:
The electric power of the thermocouples depends on cooling influenced by the environment. On a cold day on Mars ...
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Now that Perseverance is "hot" (RTG in place) and before it gets to deep space, how will it stay cool?
As soon as they are assembled MMRTGs continuously produce about 2,000 watts of heat energy. That dips only slightly when they are connected to a load and producing electrical power (about 125 watts ...
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Methane or LOX tank at Boca Chica
As we can see on this picture from Mary "@bocachicagal" on NASASpaceFlight, there are two types of tank near the test stand.
Some are black and others are white or bright and shiny metal, ...
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How to design heatshield bluntness?
How is the bluntness or curvature of a heat shield of a reentry spacecraft designed?
If the answer depends on size and mass, consider a deep space sample return "mini capsule" 50 cm in ...
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Why would the Falcon 9 Block 5 carbon fiber thermal protection material need to be hydrophobic?
This answer to Nature of “the silky black 'highly flame-resistant felt'” on Block 5 Falcon 9's, and its intended functions? contains the following:
This came into Falcon 9 design with Block 5 ...
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Are there any uncrewed spacecraft that maintain(ed) an atmosphere?
In How do phonesats stay cool? I wonder if phonesats might have had "cabin pressure" to keep the phones from overheating since they are not designed for space.
But now I'm just wondering if ...
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How do phonesats stay cool?
To the question Can a smart phone function in space? this answer says
Multiple android based phone satellites have been launched into space. (At least six according to Wikipedia). I haven't looked ...
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How do space blankets (thermal blankets) work?
On earth, blankets serve to primarily buffer temperature changes / heat transfer that would occur via convection (e.g. a blanket traps air near you so that after your body warms it, it doesn't just ...
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Why do many RTGs have finned heatsinks, when this is considered bad for radiation heat transfer?
Related: Finned heatsinks in space
Multi-fin heatsinks are not normally considered good for heat dissipation in space because adjacent fins radiate into each other, and you would be better off with ...
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