Questions tagged [thermal]

How heat affects spacecraft and space missions, or materials and methods to deal with heat.

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2answers
1k views

Insulation on rockets--why take it to space?

I'm especially thinking of the loss of the Columbia due to damage from chunks of insulation that came off. I got to wondering, why is it there in the first place? Of course it's needed while you are ...
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1answer
81 views

Is the BEAM module as good as a rigid module in terms of radiation/thermal properties?

It seems that NASA is going to stick with the BEAM module on the ISS for quite some time, and is currently using it for storage. That's pretty cool. However, I was wondering if the BEAM module could,...
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1answer
103 views

Why would it be “less bad” for hydroxylammonium nitrate monopropellant to freeze than for hydrazine?

Answers to Is it bad if hydrazine freezes on a spacecraft? Is it always kept as liquid, or can it be safely allowed to freeze and then thawed when needed? explain that while the freezing of hydrazine ...
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1answer
93 views

How many different kinds of insulation film are wrapped around the Apollo Lunar Module?

In the image shown in the question Why is the Apollo LM landing gear covered with so much thermal isolation? (also shown below) it appears that the color of the film around the bottoms of the lander's ...
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2answers
130 views

How to make a camera survive in (near) space?

I'm working on project for a high altitude camera suspended from a weather balloon in order to approximately simulate spaceflight. I'm wondering how can I make a camera survive and continue to operate?...
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1answer
203 views

What's the role of the chainmail and scale armor on InSight's WTS?

It's like taken directly from a medieval armor... The role of wind and thermal shield (WTS) deployed over the seismometer is in its name - protecting it from noise and thermal changes. This is fairly ...
2
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1answer
118 views

What was NASA's “LUROVA” Operational Thermal Computer Model analog or digital? How were capacitors used?

@GremlinWrangler's answer links to Apollo Rover Lessons Learned Applying Experiences on the Apollo Lunar Rover Project to Rovers for Future Space Exploration by Ronald A. Creel, Space and ...
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Why are RTGs different colors?

This is an image of the radioisotope thermoelectric generator (RTG) for Cassini: This one was for one left on the Moon: And this one is for the Multi-Mission RTG, used by Curiosity on Mars: One is ...
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Why the thermal imaging of Mercury's surface requires a telescope on a jet flying through an eclipse?

The NASA News Feature Chasing the Total Solar Eclipse from NASA’s WB-57F Jets describes two telescope-equipped NASA jets that will fly fast enough to spend about 7 minutes in the Umbra (totality) of ...
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5answers
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How does a solar eclipse affect satellites?

Satellites are somewhat closer to the Moon than the Earth is (Or rather, can be), and might well have the sun blocked from them. Furthermore, they can move somewhat more than the Earth, and thus have ...
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When did deep-space probes start getting wrapped in germanium-coated film?

The NASA video Juno Engineering: Precision Matters shows the Juno spacecraft on what look like it might be a spin balance table after about 02:50 and there one can ...
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1answer
226 views

How will Robotic Refueling Mission-3's liquid methane tank remain full for six months without any boil off?

Space.com's Lasers, Crystals and 36,000 Worms Will Ride a SpaceX Dragon to Space Station says: To fly on those journeys, astronauts might have to someday harvest fuel from the surface of the moon ...
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1answer
297 views

Why do the ISS' Thermal Rotary Radiators need to tilt?

This answer shows the first image below of a vintage view of the ISS. Only one of each triplet of thermal radiators is extended from each TRRJ. The ISS' solar panels articulate to modulate the ...
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3answers
4k views

Is it bad if hydrazine freezes on a spacecraft? Is it always kept as liquid, or can it be safely allowed to freeze and then thawed when needed?

After having read this answer I wondered what happens if hydrazine freezes. It looks like it is "normal" and not like water, in the sense that it contracts when freezing, unlike water which expands ...
5
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1answer
164 views

What methods are proposed for storing cryogenic fuels (esp. hydrogen) in space for months or years?

Current Launch vehicles and upper stages must only keep their fuels for minutes or hours, so they are only insulated to keep boiloff to a few % per day - I've seen 21% per day quoted for Centaur on ...
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2answers
191 views

What do the insulation and meteorite protection layers being opened on the Soyuz MS-09 spacecraft look like?

This current news item in TASS Russian cosmonaut Kononenko approaches Soyuz MS-09 spacecraft for inspection says: Earlier in the day, the two Russian cosmonauts began their six-hour spacewalk, ...
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Why are the heat sensor probes in HP3 probe spaced with reducing gap with depth?

The HP3 probe used for studying the geothermal features of Martian surface, hammers upto 5m deep and inserts a tether lined with heat sensor probes. This link shared earlier by @uhoh, is an ...
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Has the monthly average skin temp of the ISS increased during its years in orbit?

Is there a source of monthly average sun-side maximum temperatures during its (ISS) years in orbit?
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60 views

Why doesn't a regeneratively cooled engine crack due to differential expansion induced by thermal gradients?

A liquid rocket engine with regeneratively cooled chamber walls and nozzles would definitely be one among those components experiencing the steepest thermal gradients (Chamber wall inner - $3000 K$ ...
5
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1answer
543 views

Why is Adiabatic wall temperature taken as the driving temperature in rocket engines?

Going by the definition of convective heat transfer coefficient from Wikipedia (which I have started to doubt; reason follows): $h=\frac{q}{\Delta T}$, where the $\Delta T$ is taken as the difference ...
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1answer
248 views

How much wax is on the Moon? (Lunar Roving Vehicles)

I found the Cody's Lab videos from Scott Manley's video as described in this answer. Browsing through I learned from the first 30 seconds of Hot Wax Bottle? that the phase change of wax was used on ...
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1answer
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Why were individual shuttle tiles changed from white to black or black to white?

The Paper Space Scale Models website has a PDF which details changes to the STS Orbiter Markings on a per-mission basis. Most of the changes are in the tiles. It can be seen that often a single black ...
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1answer
181 views

What is a “diode heat-pipe” and why is it considered passive?

I just saw the following block quote and table (Table 4.4-1) in this answer about temperature limits of spacecraft electronic systems. A source for the document appears to be http://vibrationdata.com/...
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1answer
153 views

Which format would be useful for satellite engineers to accomplish better thermal analysis?

I am developing a software that is capable of simulating the orbit for satellites for my master thesis. The software will not be able to make thermal analysis, but I think it can still help satellite ...
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1answer
428 views

How cold is the Martian sky at night? Or the day for that matter?

If you take a simple infrared "thermometer" which is actually a lot like a bolometer and point it at a clear sky, it says "cold!" because in the wavelength range that it's using (roughly 5 to 15 ...
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3answers
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Is it normal for thrusters to “ice up”?

Towards the end of the JSSAT-14 webcast (around T+32:58), we see a thruster firing. Over the space of around 20 seconds, you can see it "icing up": What is this that's forming? Is this a normal ...
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Thermal control

I am interested in spacecraft thermal control. Is there any book on the subject with a good theoretical base that I could look into? Thanks in advance.
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What is a current/good Mass Estimating Equation/Heuristic for space radiators/heating systems?

Has anyone does any analysis for thermal control systems for manned space habitats? I know Gilmore has data for unmanned systems, but I was looking for data for unmanned systems, preferably to develop ...
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2answers
223 views

Why are deeper folds better for absorption?

The NASA News item NASA’s New Shape-Shifting Radiator Inspired by Origami describes a technique for spacecraft temperature regulation combining both a shape-changing surface and an emissivity-changing ...
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1answer
303 views

Why were early satellites produced with polished “mirror-like” surfaces?

Many/most early artificial satellites were spheres with mirror-like polished outer surfaces. I am guessing that for lower orbits the spherical shape minimized drag as well as simplified the analysis ...
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1answer
279 views

Lunar launch pad cooling

I read recently about the huge volumes of water that is sprayed on a launch pad during lift off. I remember it to be about four times as much water as fuel burned. This is done to reduce noise (energy ...
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1answer
509 views

Are there any promising next-generation space station cooling technologies?

The ISS had problems related to ammonia more than once. These problems happened in different calender years, and it seems like almost every "near miss" that makes the news about the ISS is connected ...
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What happens to Lunar (or asteroidal) regolith if sunlight is concentrated on it?

At 24:40 into this lecture, technology development scientist Laurent Sibille briefly describes an experiment done with a regolith simulant for Lunar Mare. The process of producing oxygen and reusing ...
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How does “temperature” work in vacuum? [duplicate]

To conduct heat, a medium is required (e.g. Atmosphere) But at higher altitudes atmosphere is too thin, yet Wikipedia states temperatures in the thermosphere can rise to 2,000$^{\circ}$C ...
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1answer
744 views

What kind of thermal protection system does the Dream Chaser have?

What is the plan for a thermal protection system on the Dream Chaser and what advantages will it have over the Space Shuttle TPS?
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2answers
392 views

Mathematically, what is the argument in favor of skipping reentries?

As a tangent while looking for numbers for the L/D ratio impact on entry profile, I came upon this site which seemed to favor skipping reentries in almost all cases. Reading further, I realized that ...
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4answers
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How will Bennu's volatile compounds stay cool and unmodified by the heat of re-entry (OSIRIS-REx)?

Watching the video in this NYTimes article NASA Aims at an Asteroid Holding Clues to the Solar System’s Roots I realized for the first time how the samples actually make it back to Earth. The ...
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1answer
842 views

Why does the side of the LEM look almost black in this photo? Did that cause problems?

After reading this answer about the RTGs used on the Lunar surface, I added some of the images from the Wikipdia article Apollo Lunar Surface Experiments Package into this answer, where I noted that ...
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1answer
447 views

What were the uses of the RTGs in the Apollo spacecrafts?

I was listening to the Plutonium episode of "the Elements" on the BBC, and between 07:00 and 08:30 they talked about uses of plutonium such as spacecraft power and heat. While the returning astronauts ...
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1answer
176 views

Could IR space telescopes and other very cold devices use Zeeman slowers effectively in the near term?

Infrared telescopes need to be very cold (often below 10 K) to be effective. So do a few other miscellaneous things, including superconductors, if we ever use them in space for e.g. mass drivers or ...
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1answer
156 views

What thermal effect does the Sun have on spacecraft that are roughly the same distance from the sun as the earth is?

What thermal effect does the Sun have on spacecraft that are roughly the same distance from the Sun as the Earth? Specifically, do spacecraft need to constantly rotate so that one side doesn't get ...
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2answers
189 views

How close are Zeeman slowers to being useful for general cooling in space?

Related to Are there any promising next-generation space station cooling technologies?, I'm wondering specifically about a technology that hasn't been mentioned there: Zeeman slowers. Since these are ...
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1answer
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Has any technology been demonstrated that allows a useful payload to survive at least one month on Venus' surface?

According to the Wikipedia article on Venera-D, A lander, based on the Venera design, is also planned, capable of surviving for a long duration on the planet's surface. The surface of Venus has ...
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1answer
2k views

How long is it feasible to store cryogenic fuels?

Working with liquid nitrogen all day, I am constantly bothered by their boiling away, forcing me to go get more from the storage dewar. Likewise should be the case with any cryogen, e.g. LH2 and LOX ...
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2answers
508 views

How can I make robust guesses about waste heat from satellites?

For a university project I'm making thermal assumptions and introductionary design of a small satellite. Satellite electronics use around 30W energy in total (inc. Camera, on board computer etc.) . ...
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1answer
388 views

How much heat did the Sabatier hardware add to the ISS heat profile?

A sort-of follow-up to Why does the International Space Station produce so much methane? In 2010 Sabatier hardware was integrated into the regenerative environment control. The Sabatier hardware ...
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1answer
1k views

What is the maximum velocity at which Soyuz TMA-M may transit through Earth' atmosphere at reentry without a heat-shield?

A quick follow-up to Re-entry Heat Shield Alternative Instead of looking for an alternative to heat-shield, I'd like to draw from analogous naval tactics I heard about; Back in the 1950's to 1960's, ...
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1answer
6k views

What material properties would be necessary to shield a lander from the environment of the Venusian surface?

On March 1, 1982, the Venera 13 lander survived for 127 minutes in an environment with a temperature of 457 °C (855 °F) and a pressure of 89 Earth atmospheres (9.0 MPa). This says nothing of the ...
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1answer
2k views

What is the cause of discoloration along the edges of the Quest Joint Airlock thermal cover?

I've noticed this discoloration / stains / burn marks along the edges of the Quest Joint Airlock thermal cover on the hatch before, but they seem even more pronounced and contrasting with the cover's ...
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1answer
356 views

What is the point of rotation of an “umbrella ship”

Some nuclear powered spacecraft designs have been entertained where the radiator is arranged in a plate geometry which rotates. For example: http://www.projectrho.com/public_html/rocket/realdesigns....