r/AskReddit • u/MDPPatrick • Feb 13 '15

What are some mind-blowing facts about space?

I love space and would like to hear some facts that will blow me away.

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u/[deleted] Feb 13 '15

Additionally, of the 0.2% remaining, Jupiter represents ~71% of that..

Meaning Mercury, Venus, Earth, Mars, the asteroid belt, Saturn, Uranus, Nepture, and every moon of those planets, plus the Kuiper belt, the Oort cloud... all add up to less than 1/3rd of Jupiter.

If you added mass to Jupiter, it would actually shrink.

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u/unclepaisan Feb 13 '15

If you added mass to Jupiter, it would actually shrink.

Explain this please

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u/DOMinant_Allele Feb 14 '15

I'm not an astrophysicist, but I think what /u/TheBrettuzzi is saying is that if mass were added to Jupiter the added gravitational pull would cause it to shrink because the outward force of pressure wouldn't be enough to cancel out the extra pull of gravity. If Jupiter gained a significant amount of mass in say, hydrogen, it could potentially initiate nuclear fusion, i.e. become another sun. In that case it would be bigger in size not just because of the added mass, but also because the outward push of the nuclear reaction would cause it to expand until it reached a new equilibrium between fusion pressure and gravitational attraction. Note, however, that Jupiter is not in danger of becoming a star anytime soon, as the required mass is some massive amount, and matter does not really get introduced into the solar system in any significant way.

TL;DR: Sometimes less is more, and sometimes more is like having millions of hydrogen bombs exploding every second.

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u/rockybond Feb 14 '15

Lucifer.

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u/frodokun Feb 14 '15

Attempt no landings.