Ask Praise Science: The Vacuum of Space, the Human Body, and You!

This is the #3 Google image result for the search term 'total recall'. I was sure it would be the first.

1 trillion Internet years ago (Ed. note: in late November), the ever inquisitive Stuart sent Praise Science the following email:

Dear Science, Praise,

Recently I have re-watched the movie SUNSHINE. The concept of traveling to the sun in a spaceship still seems to ridiculous to me, but it's a very well-done sci-fi thriller with accurate Science in it. I suggest you see it.

However, there is one part that bugs me and I wish for everyone at Praise Science to clarify. In the movie there is a scene where two men are outside the ship for a brief moment without suits. Long story short, one doesn't make it back and his body freezes up like the T1000 (space being around -273 degrees Centigrade). Once he crosses the ship's sunshield threshold, his body incinerates within 1 second. I trust that is accurate.

However, I was always under the impression that the human body is shaped under constant atmospheric pressure on the outside, and once exposed to the vacuum of space, will immediately explode or inflate or something along those lines. Therefore, I find the plausibility of a human surviving in space without a suit for longer than .01 seconds highly unlikely.

Please do your best to clarify whether the exploding human body is just another Hollywood rumor or whether the Science of SUNSHINE is inaccurate. I'll sleep better.

Thank you,

Stu Haury

SORRY FOR MAKING YOU LOSE SLEEP STUART! Good question. What young Science-ling hasn't pondered this very scenario while lying awake at night? Indeed, this very question was asked of NASA in 1997, ten whole years before such modern and thoughtful Science-fiction films as Sunshine ever saw the light of day (lulz, was the Internet even real in 1997??). But don't read that FAQ yet, because here is our sexy PS answer:

No, Stu. Your body won't explode in a vacuum. If you really want to jump out the airlock without a suit, you probably have at least 30 seconds to a minute before any "serious" injury occurs. The human body (and its interior systems) has a certain equilibrium between porousness and airtight-ness that allows pressure to escape slowly enough to avoid violent decompression using the regular processes of respiration. Just make sure to breathe out slowly. However, things might get complicated after that short period of time because you can't hold your breath. Retention of oxygen in the lungs during rapid decompression (aka atmosphere to a vacuum, deep water to shallow water, high altitude to low altitude, etc), will lead to "the bends", or decompression sickness (then you die). Additionally, if exposed to the Sun, you will enjoy the pleasant sensation of massive sunburns while simultaneously experiencing rapid frostbite to any exposed skin. So basically, if you want to launch your body into space, do it just like they did it in Sunshine. Here is a clip of the exact scene in question. The movie gets it right on. But don't be that guy. You know, the one who fucked up and is now floating out into the void.

Hope that answers your question Stu. Sorry for lagging. Hopefully you haven't had blast out of an airlock or anything since you asked the question. Also, see Sunshine if you haven't already. It totally rules ass.

Ask Praise Science: Episode 2, Attack of the Kelvins

For our second edition of Ask Praise Science, reader Stu submits the following question:

How do astromomers / scientists / temperature-reading obsessed maniacs determine surface temperatures of stars? For instance, a blue-white star is known to be hotter than 30,000 degrees F on the surface. I know this has something to do with light waves and their color, but how can scientists be so accurate? And, on a similar tip, how about surafce temperature of planets we have not fully explored (i.e. Saturn's surface (well, its clouds) is quite cold, about -220 degrees F)?

Very good question. It definitely is pretty easy to take accept the information we receive about the universe as a whole from astrophysicists as given because, well, they are astrophysicists after all. It's not like they are making this shit up. As it is within all Scientific disciplines, standards and best practices have been developed in order to normalize research and findings. This is especially true for the physics of stars, formally known as stellar astrophysics, because all of our findings are based on the observation of light that in many cases is millions or billions of years old (except in the case of our own Sun and other local stars).

So how do Scientists "know" the temperature of distant stars (and other celestial bodies)? They use something known as the Stefan-Boltzman Law, which determines the effective temperature of a 'black body'... errr... those links are getting dangerously mathy and physicsy. Basically what this means is creating an estimate for the overall (or maybe 'average') temperature for a celestial object, since temperature can vary widely across the surface of said object. This is done by measuring the luminosity, or brightness, of the object and its surface area, and then calculating the temperature of an imaginary 'black body' with the same attributes according to the law mentioned above.

So the stellar "temperatures" that we read in all the interesting astrophysics articles that everyone surely read everyday are more like working estimates based on the purely observable data we can get by looking at stars through telescopes (size, brightness, etc.). This temperature in turn becomes another characteristic that we can use to classify stars and is in fact one of the variables used on the Hertzsprung-Russell diagram, or the Cliffs Notes of astrophysics.

As for planets like Jupiter, I'm pretty sure we know the atmospheric temperature because we've been there. Or at least our unmanned space missions have. As for other distant planets, I assume they use the same method as above.

That was long. Hopefully it allows you all, especially Stu, to praise Science in a more efficient fashion.

Ask Praise Science, Episode 1: Time Zones on the Moon

Last week, loyal reader Elliot relayed to as an important Science-related question that a drunk homeless man asked him: How many timezones does the Moon have?

Wow. That is a fucking good question. Since Google yielded no useful results (seriously, if someone can find an decent answer to this question on the tubes, we'll give them 100 Science Points) we decided to institute what will hopefully become a regular feature on PS: Ask Praise Science, where you, the readers, ask us important (and hopefully non-Googleable) Science-related questions that we try our best to answer for you. So on that note, here is our best answer to Elliot's question:

How many timezones are on the Moon? Well, that depends on how you look at it. Once upon a time on Earth, Scientific men invented timezones so that uncivilized provincial train station employees would no longer make them miss their trans-continental trains to important Scientific events across the country by relying on primitive instruments and concepts such as sundials and solar time. What this means is basically we have a timezone for each hour of the day, so things like transportation and communications can easily be standardized.

So, the concept of a timezone itself is essentially contrived to satisfy a functional human requirement. Based on this, we have to ask whether or not the Moon actually NEEDS timezones. Near-future moon bases and missions will likely use a standardized Earth time for operational purposes, since the length of the lunar day (or a full lunar cycle) is approximately 655.75 hours long as opposed to Earth's 24 hours (for all you Pink Floyd fans, the dark side of the moon is myth; all parts of the moon are equally exposed to the sun at some point during a full lunar day).

Taking this into consideration, if the traditional notion of timezones is applied to the lunar day (one timezone per hour) that would mean that the Moon would probably have 655 or 656 timezones. If the 24 timezones of Earth were to be projected onto the moon, each time zone would be about 27.3 hours apart, which kind of defeats the purpose of timezones to begin with. Both of these options would most likely be totally counter-productive to any Earth-Moon synchronization efforts. I say just set universal Moon-time to Greenwich-Mean-Time or something like that, and call it good.

Hopefully that wasn't too long and that it satisfies you, Elliot. Readers, if you like "Ask Praise Science", please let us know and request some more topics in the comments section!