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The car is on the sun side of space as seen by the lens flare. This means that the car will absorb high amounts of radiation, heating the car up to well over 250 degrees Celsius . A car windscreen will start to crack at around 120 degrees Celsius , most certainly not surviving at 250 degrees Celsius . Satellites need special radiators and a special covering because of these high temperatures, but this car has nothing to help with the dispersal of heat.The car is also traveling through space at over 12 miles per second. But the car's windscreen does not have a crack even after four hours. Also if the car is spinning as mentioned (shadow cools in space / sun heats up) wouldn't this create another problem, the windscreen would be in thermal expansion on one side, and contraction on the other, so why doesn't it crack and break?

Mitch
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    "we are told that space has hot and cold spots or very high and very low temperature's every 20 miles or so" find out who told you this, and never listen to them again. – Organic Marble Feb 12 '18 at 16:27
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    Black parts would heat up very much by the radiation of the Sun. But the windscreen is not black, it is colorless and transparent and will absorb very few radiation and thus heat up much less. – Uwe Feb 12 '18 at 16:32
  • So you are saying that space does not have hot and cold spots every 20 miles or so? How much would you say the windscreen would be heating up and rapidly cooling by as it travels at 12 miles per second, while spinning in space? – Mitch Feb 12 '18 at 16:37
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    @Mitch are you maybe misremembering about the thermal layers of atmosphere instead of space vacuum? – jkavalik Feb 12 '18 at 16:42
  • Surely as the car spins one side to the sun and then in to the shadow, the car would be rapidly heating and cooling, wouldn't this crack the windscreen? Even if the windscreen is absorbing little radiation, the windscreen is attached to a car that is rapidly heating and cooling. – Mitch Feb 12 '18 at 17:40
  • @Mitch why do you think it is so rapid? The car is the same distance from sun as Earth is so the sunshine is similar to a summer sunny day. And the cooling is far from fast without any air in there (it does not have th3 special radiators) so it will soon get to some thermal equilibrium depending on the rate of rotation and the temperature will probably change very little after that point. – jkavalik Feb 12 '18 at 17:55
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    Citation needed on those low levels of windshield heat tolerance. Car interiors can rapidly heat up on many occasions to quite high temperatures, and 120 F is not at all out of the question. For that matter, there are some areas of the world that get over 110 F fairly frequently. – Nathan Tuggy Feb 12 '18 at 17:55
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    When the car heats up rapidly, the heat is transfered very slowly to the windscreen because the thermal conductivity of glas is very low. It is possible to hold a glas tube into a flame with bare hands. One end is red hot, the other end does not burn the hand. – Uwe Feb 12 '18 at 17:56
  • @Nathan, sorry I'm talking about 120 degrees Celsius not F – Mitch Feb 12 '18 at 18:48
  • @Uwe, but the windscreen is actually clamped by the surround that would be changing from red hot in the sun to freezing cold in the shadow. Surely if the windscreens surround is constantly changing temperature it would cause the area that's clamped in the surroundings to shatter, in turn causing problems for the rest of the windscreen? I guess it would depend on how fast the car was spinning. – Mitch Feb 12 '18 at 19:11
  • @jkavalik, I believe space to be over 250 degrees Celsius while in sunlight, as the car in the video was and under - 250 degrees Celsius in the shadow, surely the car turning from one side to the other while travelling at over 12 miles per second, would cause high fluctuations in temperature? – Mitch Feb 12 '18 at 19:29
  • @Mitch : you know how hot is "red hot"? For steel it is about 800 to 1000 °C. – Uwe Feb 12 '18 at 19:30
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    @Mitch space has no temperature the way you understand it. There is no.medium to "hold" a temperature. All the heat transfers happen through radiation which is quite "ineffective" compared to being in atmosphere. – jkavalik Feb 12 '18 at 19:33
  • @jkavalik If it's true that the radiation is ineffective compared to the atmosphere, why do satellites need special radiators and a special covering. – Mitch Feb 12 '18 at 19:43
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    @Mitch because electronics need lower temperatures to work and they heat up when working. And to get rid of that heat the radiators are needed and they are big specifically because they are not very effective. – jkavalik Feb 12 '18 at 19:45
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    I have voted to close as the question is based on very incorrect assumptions. – Rory Alsop Feb 13 '18 at 17:52
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    @Mitch Satellites and spacecraft need radiators specifically because rapid cooling in space is not possible. Space is a very good insulator and there's no breeze to cool you down, so once you're hot, you stay hot, until you cool (Very slowly) by blackbody radiation. Thus, you need the radiators to keep the electronics and crew from baking to death from their own waste heat. The roadster - with no crew, no electronics, and no power of any kind - is slowly and evenly being warmed by the sun, and the side of the vehicle in shadow is slowly radiating that heat away like a hot coal. – UIDAlexD Feb 13 '18 at 20:40
  • @Uwe Also the Moon is very black. It heats until around 120C in a 2-week long daytime. I expect roughly the same for the Tesla. – peterh Feb 14 '18 at 11:45
  • The windscreen might already be "broken" if not cracked. One of the speculative answers to https://space.stackexchange.com/q/25262/6241 is that the haze could possibly be the windscreen delaminating and so reflecting/refracting light differently. – Baldrickk Feb 16 '18 at 10:40
  • @Uwe Glass-blowing is usually done between about 870 and 1,040 °C according to wikipedia – Baldrickk Feb 16 '18 at 10:43

2 Answers2

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The Tesla Roadster is not experiencing 250°C temperatures.

This answer to another question shows that in Earth orbit it will be just over 0°C, similar to you and me:

What's the typical temperature of a satellite orbiting the Earth?

The key plot from that answer shows that out near Mars it will be around -80°C

Nathan Tuggy
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Sir Adelaide
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    I am really unsure about this, that seems to be the main problem regarding physics and space. There is so much conflicting information by so called experts in these fields, when you look deeper into the issues none of it makes any sense. – Mitch Feb 13 '18 at 15:24
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    @Mitch If your "expert" truly told you the "We are told that space has hot and cold spots or very high and very low temperatures every 20 miles or so" bit, you need better experts. I think you're misremembering a discussion of how satellites can rotate slowly to even out heating. – ceejayoz Feb 13 '18 at 16:03
  • @ceejayoz, I remember reading this on a different site, by someone who did appear to know what they were on about, however this is not the only conflicting information I have read regarding space or physics. To be perfectly honest, if you look at the answers I have been given above, against some of the other answers on similar subjects across this site, you will also find much conflicting information on the heating and cooling properties of space. This makes it difficult for a person of my limited knowledge to find who is giving good information or who maybe giving bad. – Mitch Feb 13 '18 at 16:55
  • @Mitch Simple solution: prioritize information from verifiable experts, peer-reviewed scientific sources, etc. over random people on the internet. – ceejayoz Feb 13 '18 at 16:56
  • ceejayoz, would you say this following info is correct - unbelievably extreme temperature swings. Just past Earth's upper atmosphere, the number of gas molecules drops precipitously to nearly zero, as does pressure. This means there is almost no matter to transfer energy -- but also no matter to buffer direct radiation streaming from the sun. This solar radiation heats the space near Earth to 393.15 kelvins (120 degrees Celsius or 248 degrees Fahrenheit) or higher, while shaded objects plummet to temperatures lower than 173.5 kelvins (minus 100 degrees Celsius) – Mitch Feb 13 '18 at 17:32
  • @Mitch the solar radiation can't "heat the space" as space is exactly "nothing" and can not be heated. If the car did not rotate and keep one side facing the sun, the temperatureof that surface would get quite high, but the "average" temperature of the entire car, taking into account the shaded parts, would still be quite low. And because the car rotates, the actual temperature of the surface stays much closer to that average. The Moon gets quite hot during the "day", but much colder during the "night" - and just because these last 14 days each, if Moon rotated faster it would be less extreme. – jkavalik Feb 13 '18 at 18:03
  • "heats the space" makes no sense. Space is nothing, vacuum. If you go by a strict definition of temperature as "the temperature of a gas is actually a measure of its average kinetic energy, and kinetic energy of a particle is related to its velocity " you could say that the very diffuse gases at the edge of the Earth's atmosphere had a high temperature, but this is operationally meaningless because there are too few particles to transfer any heat to a decent sized object. – Organic Marble Feb 13 '18 at 18:06
  • @Organic Marble, well this was written on a site called Sciencing temperatures-outer-space-around-earth, this what I was saying earlier, physics and space can be very confusing when you have people who I would call experts all giving out different information. – Mitch Feb 13 '18 at 18:15
  • so just to clarify things for me, we are saying that a standard car windscreen will not crack or break in space due to rapid thermal cycling, the car in space would have no rapid thermal cycling as it would stay much the same temperatures as it would on earth, the spinning of the car is helping it remain at a constant earth like temperature. A car travelling through space at over 12 miles per second while spinning one moment into the sun the next moment away from the sun, would not cause the windscreen to fracture. – Mitch Feb 13 '18 at 18:32
  • @Mitch yep, There is nothing "rapid" about the heating and cooling so the temperatures oscillate slowly around the equilibrium during the rotation. And the speed of movement has no effect on heating neither cooling. – jkavalik Feb 13 '18 at 21:33
  • @jkavalik, thanks for all your help with the questions I had. I feel I have learnt a lot more about space through the many good answers I have received here, I do still find it difficult to accept that the black surround of the windscreen wouldn't heat up and cool enough to cause the windscreen damage, however I'm going to leave it here by thanking everyone who has replied in helping me to understand space just that little bit more. All your answers are truly appreciated. – Mitch Feb 13 '18 at 22:00
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It doesn't crack or break, because it's made of inorganic material. Chemist Richard Sachleben states in this article from Life Science Will SpaceX roadster survive Space that it will take a long time for the windshield to discolor and come apart relative to any organic material in the car (leather seats, rubber tires) and will only start to do so as the plastic in the windshield starts to decay. He believes the organics will last around a year, but gives no specific guess on the glass.

Rickest Rick
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  • I don't think this answers the question. It wasn't about ongoing material degradation caused by vacuum/radiation - it was about rapid thermal cycling. Take a glass pan from the oven immediately into some cold water and it'll shatter, inorganic or otherwise. I don't think the Tesla is undergoing the rapid cycles OP thinks it is, but that's another issue. – ceejayoz Feb 13 '18 at 16:01
  • The OP asked why the windshield doesn't crack or break. I found what little science has been printed on this issue. If the exposure to the hypothetical temperature extremes doesn't shatter the window in the first few moments of it's flight, then the clock of degradation starts ticking. Yes I avoid the conversation of hypothetical temperature issues and instead supply evidence against the title of the question. IF the title had include ...because of temp swings, I would not have added my answer. – Rickest Rick Feb 13 '18 at 16:17
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    "It doesn't crack or break, because it's made of inorganic material" Does this mean that metal or glass never cracks or breaks? – Organic Marble Feb 17 '18 at 17:18
  • @OrganicMarble good question. No we know that glass and metals crack and break all the time, but the roadster won't due to it just being out in space. HOWEVER,... if the windshield were to be struck by a micrometeorite, it would almost definitely crack, break, shatter, shimmy, and shake; But it probably won't salsa, do the robot, or the robo boogie, but of course, contradictory evidence is always welcome. – Rickest Rick Feb 19 '18 at 15:25
  • @Mitch Does this answer your question? – Rickest Rick Mar 08 '18 at 16:48