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Old 10-June-2003, 12:15 AM
skywatcher skywatcher is offline
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Default Read this

I know the post is bull but my question is does Jupitor have enough mass to create a black hole..

http://66.242.35.139/bbs/message.php...page=1&topic=3
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Old 10-June-2003, 12:27 AM
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Grand Vizier Grand Vizier is offline
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Default Re: Read this

Quote:
Originally Posted by skywatcher
I know the post is bull but my question is does Jupitor have enough mass to create a black hole..

http://66.242.35.139/bbs/message.php...page=1&topic=3
Only when turned into billions of identical Black Monoliths.

HTH
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Old 10-June-2003, 12:46 AM
skywatcher skywatcher is offline
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Default What do you mean

i didnt get it
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Old 10-June-2003, 12:53 AM
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gethen gethen is offline
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Short answer, this story is first class b******t. The big guns will probably check in shortly and explain exactly why, but I do not believe Jupiter has the mass to become a black hole. And Shoemaker-Levy didn't do anything unusual. Strange story. Grand Vizier was saying pretty much the same thing, referring to the old movie 2001. One of the monoliths was on Jupiter. Sometimes we get a little goofy here. No slam intended I'm sure.
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Old 10-June-2003, 12:54 AM
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Default Re: Read this

Quote:
Originally Posted by skywatcher
I know the post is bull but my question is does Jupitor have enough mass to create a black hole..

http://66.242.35.139/bbs/message.php...page=1&topic=3
If you compressed Jupiter enough, you could turn it into a black hole, but you'd probably have to get it down to the size of a golf ball.

To have a black hole form purely under gravity, I think you need something at least 1.6 times the mass of the Sun, or some such figure - definitely larger than the Sun.
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Old 10-June-2003, 12:57 AM
DStahl DStahl is offline
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Humph. Well, Jupiter would have enough mass to create a black hole if it were compressed to a small enough circumference--its Schwartzchild radius. But self-gravitation alone won't do it for Jupiter. It just can't collapse into a black hole, no physical way.

Neither can our Sun.

[ToSeek, you posted while I was typing. Obviously I agree with you... )

Black holes aren't some sort of wilfull rogues that can disobey orbital dynamics and flit from the center of Jupiter to eat up Earth, and then perhaps go to Andromeda for coffee and ice-cream. If there were a black hole at the core of Jupiter it would be, presumeably, in a stable orbit identical with the orbit of Jupiter...and it would require some sort of kinetic kick to make it change position.

Also, depending on the size of the black hole, I think that infalling matter would be compressed and heat up a lot. I could imagine that a black hole at the core of Jupiter might even cause infalling hydrogen to heat up enough to start a fusion shell around the black hole--what do you guys think? Is that possible, and if so, what would that look like to an astronomer on Earth?
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Old 10-June-2003, 01:56 AM
Kizarvexis Kizarvexis is offline
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Default Earth and Jupiter as black holes

Googling is fun.

Here is the Schwartzchild Radius of the Earth and Jupiter. (I got the formula from here.

radius = Grav constant * mass * 2 / C squared

grav constant = 6.6726-11 /(kg sec2)
C squared = 8.98755+16 meters per second
Earth mass = 5.97+24 kilograms
Jupiter mass = 1.900+27 kilograms

To make the Earth a black hole you have to stuff it all in a ball less than 18 millimeters across. (.0089 meter radius, approximately due to rounding)

To make Jupiter a black hole, you have to stuff it into a ball less than 5.7 meters across. (2.843 meter radius, approximately due to rounding)

By comparison, Earth has a diameter of 12,756.3 km and Jupiter has a diameter of 142,984 km (equatorial). The Sun, 1,390,000 km in diameter, would have to be squished into a ball less than 6 kilometers across (2977 meter radius, approximately due to rounding).

Kizarvexis

Added the last paragraph.
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Old 10-June-2003, 02:45 AM
wedgebert wedgebert is offline
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Man people are stupid sometimes. I'm not referring to the poster, but to one of the guys "debunking" him, Dawgy.

Quote:
Gawd, What Sh-t, this is so weak, really, I mean it.
1) Black hole would swallow/ex-sorb the planet causing so much radiation that we would be dead right now. Period end of story.
2) We would have seen a complete loss of all star light as we would pass into the event horizon.
3) Gravitational shock waves would have tore the gas off Jupiter long before the Black hole passed within the orbit of Saturn.
4) Get a life #$$ wipe
This guy is wrong in everything he says. I'm not even sure what ex-sorb means.
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Old 10-June-2003, 03:36 AM
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Quote:
Originally Posted by wedgebert
Man people are stupid sometimes. I'm referring to the poster, but to one of the guys "debunking" him, Dawgy.
nit: "You mean I'm [not] referring to the poster?"

His debunking point #4 carries some weight though. The OP looks like he took a very long walk off a considerably shorter jetty.

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Old 10-June-2003, 03:39 AM
wedgebert wedgebert is offline
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Whoops, thanks for the pointing out the mistake, I fixed it now.

The problem is that I also don't think highly of the poster
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Old 10-June-2003, 03:45 AM
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Quote:
The problem is that I also don't think highly of the poster
Ya - thats why I standby debunking point #4....

C.
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Old 10-June-2003, 04:32 AM
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Its important to keep in mind that the minimum stellar core mass needed in order to create the conditions for a black hole requires about 3-5 solar masses in the core of a star. So while you can calculate the schwarzschild radius for objects of different masses (for the Sun this radius is 3.0 km) actually getting the substellar mass and most stellar mass objects down to the radius needed to create that condition is just about physically impossible.
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Old 10-June-2003, 04:33 AM
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Grand Vizier Grand Vizier is offline
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Default Re: What do you mean

Quote:
Originally Posted by skywatcher
i didnt get it
Sorry, skywatcher - late-night sardonic mood . It's a reference to the movie 2010 - Odyssey 2, sequel to 2001. In it, the space people turn Jupiter into a star (not a black hole) by compressing its core - their mechanism is to turn lots of Jovian material into black monoliths. I was making the inference that if you had that degree of control you could go further and turn it into a black hole if you wanted.

To add to what other posters have said here, there is no known lower limit to the mass of a black hole, but there is also no known mechanism for black holes of less than the mass of about the Sun to form right now (well, unless you have access to Black Monolith Technology [TM] :wink: ). Very small black holes might have formed in the Big Bang, but they will all have evaporated by now via a process called Hawking Radiation.
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Old 10-June-2003, 04:34 AM
RichField RichField is offline
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It's interesting that, even if Jupiter did become a black hole, there really wouldn't be a significant effect on the rest of the solar system. There may be some finer points of orbital dynamics I'm neglecting, but if it suddenly popped down to the Schwartzchild radius that Kizarvexis calculated we'd just have the same mass in a slightly smaller area.
The gravitational field would be drastically different over the area where the mass of the planet once was, but outside that region, everything else would just see Jupiter's mass where it should be.

I think the fear a "black hole in our solar system" generates is due to the fact that a black hole can't form unless its mass is greater than the sun's and that would be a major addition to the solar system. Something that big would have major and far reaching effects, but if it has to travel here, it should be noticable a long way off. Simply compressing existing mass to some critical radius shouldn't be like pulling a drain plug.

The tranformation of Jupiter into a black hole would be a great disappointment, to me personally, because I enjoy observing Jupiter, but who knows, a black hole might give a good show once in a while.
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Old 10-June-2003, 04:42 AM
wedgebert wedgebert is offline
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Now to be percise, many black holes form from neutron stars that are only about 1 - 3 solar masses. However the stars that went supernova and formed the neutron stars were much more massive to begin with.

And yes, if Jupiter (or even the Sun) suddenly collapsed into a black hole, we wouldn't really notice. Well, in the sun's case, it would get a little dark and cold on Earth. But at least our our orbit would be stable and we wouldn't have to worry about Sol turning into a red giant and engulfing us.
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Old 10-June-2003, 04:52 AM
Kizarvexis Kizarvexis is offline
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Default blackholes

Quote:
Originally Posted by dgruss23
Its important to keep in mind that the minimum stellar core mass needed in order to create the conditions for a black hole requires about 3-5 solar masses in the core of a star. So while you can calculate the schwarzschild radius for objects of different masses (for the Sun this radius is 3.0 km) actually getting the substellar mass and most stellar mass objects down to the radius needed to create that condition is just about physically impossible.
Yep, totally agree which is why I said you would have to stuff the masses down to size. I guess I could have been a little clearer for the need of outside help to make this happen.

Kizarvexis
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Old 10-June-2003, 08:19 AM
pmcolt pmcolt is offline
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Quote:
Originally Posted by wedgebert
Well, in the sun's case, it would get a little dark and cold on Earth. But at least our our orbit would be stable and we wouldn't have to worry about Sol turning into a red giant and engulfing us.
Wow, how's that for glass-half-full thinking?

If Jupiter (or the Sun) somehow collapsed in this manner, would we notice any Hawking radiation effects? I googled and found a formula relating temperature to Schwartzchild radius, but not knowing anything about blackbodies, or thermodynamics, or...really anything, any answer I got would be meaningless to me.
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Old 14-June-2003, 03:56 AM
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Default Re: What do you mean

Quote:
Originally Posted by Grand Vizier
It's a reference to the movie 2010 - Odyssey 2, sequel to 2001.
Nitpick:

The book was titled 2010: Odyssey 2.

The movie was titled 2010: The Year We Make Contact.
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Old 14-June-2003, 04:10 AM
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Default Re: What do you mean

Quote:
Originally Posted by tracer
Quote:
Originally Posted by Grand Vizier
It's a reference to the movie 2010 - Odyssey 2, sequel to 2001.
Nitpick:

The book was titled 2010: Odyssey 2.

The movie was titled 2010: The Year We Make Contact.
Actually, I forgot my mantra - always check imdb.com before mentioning a movie. We're both right - and we're both wrong:

http://us.imdb.com/Title?0086837

...according to which the film is called just 2010. But:

Quote:
Also Known As:
2010: Odyssey Two (1983) (USA: original script title)
2010: The Year We Make Contact (1984)
However, yours is the general release sub-title, and I typed '2' not 'Two', so I hereby concede that you are almost totally, but not quite, right.
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