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[#] Thu Aug 27 2015 07:57:22 EDT from IGnatius T Foobar

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The short answer is that Jupiter isn't big enough.  Hydrogen on the Sun isn't "burning" as we know it -- that would combine with oxygen and release water.  There's no oxygen at the Sun.  Its mass and resulting gravity cause the hydrogen to begin fusing into helium, which is an exothermic reaction.

So for Jupiter to ignite we'd need to increase its mass by about three orders of magnitude (Jupiter is about 1.9*10^27 kg, the Sun is about 1.9*10^30 kg).  This sounds simple enough, we just need to find some more Jupiter-stuff and throw it on the pile, right?

Are there any physicists around who can check my work here?  ;)

[#] Thu Aug 27 2015 17:09:02 EDT from zooer

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You hate solar power don't you?

[#] Thu Aug 27 2015 19:40:47 EDT from vince-q

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Your math is correct, IG.... *if* you are wanting Jupiter to be a sun-like star.

If you'd settle for something smaller, it turns out that the requirement for Jupiter to "become" a star (self sustaining hydrogen fusion reaction in its core) is lots less. 8 Jovian masses does the trick.

[#] Thu Aug 27 2015 21:34:28 EDT from IGnatius T Foobar

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I don't hate solar power itself, I hate people who ignore its lack of scalability relative to conventional sources of energy and try to tax them into price parity. That's not the same thing.

Ok, so Jupiter * 8 == star. How long would the reaction last, though, if we only gave it the bare minimum mass?

In any case, I'm glad we have a physicist here in the pub with us, and not a cosmologist. Cosmologists are morons who make stuff up. A particularly stupid one named Stephen Hawking just said this week that you can pass through a black hole and come out in another universe. Yeah, I saw that movie 36 years ago. He then went on to say that if something goes into a black hole, it turns into a hologram. You cannot make this crap up! I wonder if he's trying to out-moron Dawkins and Tyson.

[#] Sun Aug 30 2015 04:20:02 EDT from mo

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Black holes shenanigans: You go over the rim and come out a Rimmer?  Scary!!

[#] Sun Aug 30 2015 20:40:11 EDT from zooer

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[#] Mon Aug 31 2015 17:35:11 EDT from vince-q

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I'd have to go and dust off the math to get a precise answer on the expected lifetime of a star starting life with 8 Jovian masses. Off the top of my head a good guestimate would be 800 million to 1.5 billion years.

The smaller the initial mass of any star, the longer it spends before becoming a dwarf. In this case, it would 'almost' be a dwarf at birth.

The dwarf lifetime of a small mass star is hugely long. Again, if I remember this 40-plus years ago exposure to the thermonuclear "chain of events" in a small mass decaying star. There is no nova event; and certainly no supernova event - these are what speeds up the end-stage of most stars. It won't even do the "red giant" thing - not enough mass. It will die a very very slow and very very boring death. Which, strange as it may seem, is ideal for the concept of Jovian moons developing life. They'd have, as we would say in Philly, "ooh-gobs" of time in which to do that!!

But Jupiter itself is nowhere near massive enough for that stuff. Any life developing on Io or Europa will have to do that on its own (or have help from The Monolith!!)<evil grin>.

[#] Mon Aug 31 2015 17:36:04 EDT from vince-q

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[#] Mon Sep 14 2015 08:09:10 EDT from IGnatius T Foobar

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Europa is Jupiter's "area 51" -- it's where they hide the secret evidence of visitors from Earth having landed.

[#] Mon Sep 14 2015 10:27:56 EDT from zooer

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That is so 2010.

[#] Thu Oct 15 2015 01:35:09 EDT from ax25

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Europa my old friend... We'll be the Pirate Twins again.  Bartender, I seem to have dropped my glass.

[#] Thu Nov 05 2015 11:14:56 EST from IGnatius T Foobar

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We're pouring the special "Jupiter Brew" today.

But you'll need to supercool it to get it back into a liquid state.

[#] Wed Nov 11 2015 23:39:18 EST from ax25

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About time.  I was about sobered up.

[#] Sat Nov 21 2015 13:02:51 EST from IGnatius T Foobar

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Anyone for darts?

(the *fun* version where you throw them at each other instead of at the dart board)

[#] Sat Nov 21 2015 16:40:37 EST from zooer

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How about Jartz, but we have to sharpen them first.

[#] Mon Nov 23 2015 13:46:36 EST from IGnatius T Foobar

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Those have to be used outside?

[#] Mon Nov 23 2015 16:24:08 EST from zooer

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If you are a pussy you use it outside.

[#] Mon Nov 30 2015 10:52:06 EST from IGnatius T Foobar

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If you use it correctly, the inside and the outside become one and the same.

[#] Mon Nov 30 2015 15:20:11 EST from zooer

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I am not talking about the new style of Jartz, I am talking about the old kind, a large metal spike with fins.  A large dart.

[#] Mon Nov 30 2015 16:11:33 EST from IGnatius T Foobar

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Sure, go ahead and use the non-exploding kind if you want to be BORING.

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