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How Big is the Biggest Possible Planet?
Discover ^ | 4 Aug, 2017 | Corey S. Powell

Posted on 08/05/2017 4:01:54 PM PDT by MtnClimber

Last week, a team of astronomers reported the first potential discovery of an exomoon–a satellite orbiting a planet around another star. Part of what is so striking about the report is the scale of this possible planet-moon system. In this case, the “moon” appears to be about the size of Neptune; the planet it orbits is some 10 times the mass of Jupiter, or about 3,000 times the mass of Earth!

The system pushes at the limits of how we normally categorize objects in space and invites questions about where we stand in the scale of things. What is the biggest possible planet? Viewed through the full range of possibilities, is Earth a big planet or a small one?

There are two ways to come at the question, depending on what you mean by “big.” If you think of the size of a planet in terms of mass, then there is a specific but rather technical answer. Planets are defined as bodies that do not generate their own energy from nuclear fusion. Any planet more than about 13 times the mass of Jupiter (4,o00 Earth masses, roughly) generates enough heat and pressure in its core to trigger limited fusion reactions of deuterium, a heavy isotope of hydrogen. At that point, the object is considered a brown dwarf instead of a planet.

The nuclear-ignition boundary between planet and brown dwarf is based on hidden interior processes, however, and it is not at all obvious from the outside. The critical mass for fusion also depends on on the mix of elements inside the object. For a plausible range of compositions, the cutoff point could be anywhere from 11 to 16 times the mass of Jupiter. If you want the full hairy details, they are here.

(Excerpt) Read more at blogs.discovermagazine.com ...


TOPICS: Astronomy; Science
KEYWORDS: astronomy; exomoon; science; xplanets

1 posted on 08/05/2017 4:01:54 PM PDT by MtnClimber
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To: MtnClimber

Good thing we are not a brown dwarf!


2 posted on 08/05/2017 4:04:15 PM PDT by MtnClimber (For photos of Colorado scenery and wildlife, click on my screen name for my FR home page.)
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To: MtnClimber

You mean a dwarf of color.


3 posted on 08/05/2017 4:06:44 PM PDT by Joe 6-pack (Qui me amat, amat et canem meum.)
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To: Joe 6-pack
You mean a dwarf of color.

Yes and it din do nuffin.

4 posted on 08/05/2017 4:09:16 PM PDT by MtnClimber (For photos of Colorado scenery and wildlife, click on my screen name for my FR home page.)
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To: Joe 6-pack

A ‘little person’ of color. Or maybe ‘little planet’ in this case. We’ve already offended Pluto enough, can’t we all just get along?


5 posted on 08/05/2017 4:10:18 PM PDT by Telepathic Intruder
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To: MtnClimber

Well, I would think Krypton represents the upper limit of a planet’s size for stability.


6 posted on 08/05/2017 4:15:59 PM PDT by Dr. Sivana (There is no salvation in politics.)
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To: MtnClimber

It’s huuuuuuuuuuuge


7 posted on 08/05/2017 4:16:10 PM PDT by NonValueAdded (#DeplorableMe #BitterClinger #HillNO! #cishet #MyPresident #MAGA #Winning #covfefe)
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To: MtnClimber

Would it be bigger than Michael Moore?


8 posted on 08/05/2017 4:16:21 PM PDT by tumblindice (America's founding fathers: all armed conservatives)
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To: MtnClimber

Hmmmmm.....

Three times sixteen......

Carry the four.......

Multiply by seven.....

The official answer from the American Society of Measuring Stuff is

“Pretty big”.


9 posted on 08/05/2017 4:19:12 PM PDT by blueunicorn6 ("A crack shot and a good dancer")
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To: MtnClimber

Every good Alpha Centaurian knows the largest planet possible is 2.44 million quadittarons.


10 posted on 08/05/2017 4:21:13 PM PDT by LeoTDB69
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To: MtnClimber

You could rack up a whole lot of frequent flyer miles living on such a planet.


11 posted on 08/05/2017 4:31:11 PM PDT by Timpanagos1
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To: MtnClimber

> critical mass for fusion also depends on on the mix of elements inside the object.

That’s my answer. What I’d like to see is 1000x Jupiter size composed of PU...but not too close to feel it.

At the rate of dense islams pinching off, Earth could become a death star soon.


12 posted on 08/05/2017 4:35:08 PM PDT by soycd
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To: Joe 6-pack

You mean a little person of color.


13 posted on 08/05/2017 5:55:27 PM PDT by mkleesma (`Call to me, and I will answer you and tell you great and unsearchable things you do not know.')
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To: MtnClimber; camle; Alkhin; Professional Engineer; katana; Mr. Silverback; MadIvan; agrarianlady; ...
Red Dwarf Ping!


14 posted on 08/05/2017 6:00:42 PM PDT by null and void (ObamaCare, giving the government the power of life and death over Americans since March 23, 2010...)
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To: MtnClimber

13 times bigger than Jupiter? Liberals, we found the perfect place...(NeverTrumpers, you can go, too.) for you...


15 posted on 08/05/2017 6:06:53 PM PDT by Deplorable American1776 (Proud to be a DeplorableAmerican with a Deplorable Family...even the dog is DEPLORABLE :-))
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To: null and void

as long as they don’t wanna say “hell-o 2 u”


16 posted on 08/06/2017 8:06:06 AM PDT by camle (keep an open mind and someone will fill it full of something for you)
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To: MtnClimber
Note: this topic is from 8/05/2017. Thanks MtnClimber.
 
X-Planets
· join · view topics · view or post blog · bookmark · post new topic · subscribe ·
Google news searches: exoplanet · exosolar · extrasolar ·

17 posted on 10/10/2018 11:47:33 PM PDT by SunkenCiv (and btw -- https://www.gofundme.com/for-rotator-cuff-repair-surgery)
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