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If an astronaut threw a cup of coffee into space, would it freeze, or boil off into gas?

This was tested nearly sixty years ago. Using a very large cup filled with 95 tons of water. An empty second stage of a Saturn I under test was used. Only the first stage should be tested but with ...
Uwe's user avatar
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51 votes
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Why exactly do robots freeze? How could we engineer around it?

There are many things that change at low temperatures. You already mentioned batteries, which are problematic for two reasons: First, liquid electrolytes get frozen at some point. Second, chemical ...
asdfex's user avatar
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43 votes
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Why cool engines with fuel as opposed to oxidizer?

Whatever you use as a coolant will become hot. Hot oxygen will (a) vaporize, making the plumbing somewhat more difficult, and (b) react with and erode (or maybe even ignite) the cooling channels, ...
pericynthion's user avatar
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39 votes

Temperature of the moon 4ft off the surface

We are used to talking about the temperature at a given location, but that's because we are used to living in a sea of air. The reality is that locations don't have temperatures, substances do. When ...
Mark Foskey's user avatar
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32 votes

How can electronics on board JWST survive the low operating temperature while it's difficult to survive lunar nights?

If surviving lunar nights are difficult to ensure the survival of the electronics, say on lunar rovers, in the low temperatures, The temperature itself is not the primary reason. Lunar nights are ...
Hobbes's user avatar
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31 votes

If an astronaut threw a cup of coffee into space, would it freeze, or boil off into gas?

It would not freeze into a block. It would quickly expand and boil, but not in a rolling boil. Without pressure, bubbles would form throughout the coffee and expand rapidly, causing it to spray out of ...
Mark Foskey's user avatar
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30 votes

What stages of distress occur to a person when there is a small hull breach in space?

To understand subjective symptoms of a hull breach, it is important to remember that respiratory drive (the sensation of shortness of breath) is driven by blood CO2 level, not blood O2 level. As long ...
Woody's user avatar
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29 votes
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How can electronics on board JWST survive the low operating temperature while it's difficult to survive lunar nights?

From Status of the JWST Sunshield and Spacecraft found in @Antzi 's answer: Most of the electronics is on the "hot side" but there needs to be some conventional electronics on the cold ...
uhoh's user avatar
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28 votes
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Why does the ISS need thermal blankets if the Sun is hot?

As noted in another question, the ISS faces some pretty hot temps. Remember, the Sun heats radiantly. When you're sitting in that much radiant heat, without an atmosphere to dissipate it, you're going ...
Machavity's user avatar
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26 votes

How can electronics on board JWST survive the low operating temperature while it's difficult to survive lunar nights?

Source: Me. I currently work as a systems engineer on JWST. JWST will operating from the 2nd Lagrange Point (aka L2), which is approximately 1.5 million km (or 930,000 miles) past the Earth in Sun-...
sohowsgoing's user avatar
26 votes
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Why is the James Webb Space Telescope temperature not shown?

According to the NASA blog on Dec 26: Separately, overnight, the temperature sensors and strain gauges on the telescope were activated for the first time. Temperature and strain data are now ...
Avery's user avatar
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25 votes
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How are the electronic circuits in interplanetary missions protected from extremely low temperatures?

Space in the vicinity of the Sun is not that cold, perhaps even out to Jupiter. One side of the spacecraft will be receiving sunlight while the side shielded from sunlight radiates into empty space. ...
David Hammen's user avatar
24 votes

Why exactly do robots freeze? How could we engineer around it?

Purely based on an operational standpoint of semiconductive devices, equivalent resistances are considerably higher at low temperatures, and thus any calibrated circuit or component, including Rcomps, ...
FluffyFlareon's user avatar
17 votes

Why cool engines with fuel as opposed to oxidizer?

The specific heat capacity of the fuel is higher than that of the liquid oxygen at the operating temperature/pressure, hence for the same rate of flow, using the fuel cools better ... and apart from ...
MikeW's user avatar
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17 votes

Why exactly do robots freeze? How could we engineer around it?

The main obstacle is the existence of liquids. Liquid phase is quite "fragile" and in contrast with gases and solids, exist in pretty narrow conditions. Without a liquid phase, a lot of ...
fraxinus's user avatar
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17 votes

What caused the JWST Instrument Radiator temperature to start cooling faster on day 34?

That is very likely the day the instrument went to active cooling. For a number of reasons they wanted to cool the instrument slowly, mostly to avoid any ice freezing on it. In fact, there's an ...
PearsonArtPhoto's user avatar
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17 votes

What's the typical temperature of a reactor core in a nuclear thermal rocket?

In general, the temperature is as high as they can get away with without melting, eroding, or weakening the reactor core -- this is also the motivator for unusual reactor core styles such as particle ...
ikrase's user avatar
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15 votes
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Why is the Apollo LM landing gear covered with so much thermal insulation?

Everything of the Lunar Module should be as light as possible. Therefore no thick-walled, heavyweight, pneudraulic-type struts were used to absorp the landing shock but lightweight aluminum honeycomb ...
Uwe's user avatar
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15 votes

Temperature of the moon 4ft off the surface

Depends on emissivity, absorptivity, shape, orientation, illumination, etc. of your thermometer. At such a location, there's nothing of any thermal significance except the radiation field. The ...
John Doty's user avatar
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14 votes
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What is the surface temperature distribution of Venus?

Venus's thick atmosphere ensures that at a given elevation with respect to Venus's geoid (which is really close to a sphere!) there is precious little variation in temperature across the planet. ...
Tom Spilker's user avatar
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14 votes
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Is the cupola, on the inside of the ISS, cold or warm to the touch?

The windows of the Cupola are not made of a single pane. When not shuttered, the Cupola windows present a four layered front to potential impactors: a debris pane, two pressure panes, and an ...
Uwe's user avatar
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13 votes

Why does the ISS need thermal blankets if the Sun is hot?

Insulation can function in both ways, keeping heat on whichever side is desired. In space limiting the amount of thermal input from the sun is very valuable since that heat is easily acquired but hard ...
Saiboogu's user avatar
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13 votes
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What was the temperature of the Apollo 11 moon landing zone?

Apollo 11 deployed the Early Apollo Lunar Surface Experiments Package (EASEP), a set of scientific instruments that measured various parameters on the moon and transmitted them back to the earth, this ...
Mark Omo's user avatar
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13 votes
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Chandrayaan 2: Why is Vikram Lander's life limited to 14 Days?

Orbiting satellites can still have problems with eclipses, from loss of both power and heat but the total time is normally measured in minutes so simply having enough battery power to keep electronics ...
GremlinWranger's user avatar
13 votes

What stages of distress occur to a person when there is a small hull breach in space?

Supplementary answer For your timeline, it's important to note that the pressure drop is not even remotely linear. The flow through the leak is large at first because the differential pressure is ...
Organic Marble's user avatar
12 votes
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How do astronauts brew tea on ISS and what brewing temperature is common?

The water temperature for restoring products, making tea and coffee is different: + 85˚ С or from + 25˚ С to + 42˚ С - depending on what the cosmonaut has on the menu. Hot water is used mainly for the ...
A. Rumlin's user avatar
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12 votes
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Astronauts of Apollo 11 facing extreme temperatures

So, the surface temperature can even vary a bit more: Surface temperature Minimum Mean Maximum Equator 100 K 250 K 390 K 85°N N/A 150 K 230 K SOURCE But that problem is not as big as it looks. The ...
CallMeTom's user avatar
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12 votes

Are JWST displayed temperatures equilibrated to stable?

Wikipedia page for MIRI mentions that the science module it will be installed in has a target temperature of "about 40K". Several bits are in that neighborhood now, so yes I'd agree that ...
BowlOfRed's user avatar
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11 votes

How does solid propellant mean bulk temperature influence solid rocket thrust and specific impulse?

Increasing Propellant Mean Bulk Temperature (PMBT) increases the burn rate which increases the thrust and causes the motor to burn out sooner. The opposite is true for decreasing PMBT. This graph ...
Organic Marble's user avatar
11 votes
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Would it be possible to power a Venus lander using a temperature differential?

High temperature in itself is useless. You need a temperature differential, just like the RTG exploits the difference between the temperature of the Plutonium and that of outer space. Kinetic energy (...
Hobbes's user avatar
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