Astronomers have sighted a very dense planet-sized object that orbits its parent star in just four days and six hours.

The object, COROT-exo-3b, fits into the category of a failed star known as a brown dwarf, but the team that made the discovery has not ruled out the possibility that it is a planet. Brown dwarfs are failed stars. They burn lithium but are not massive enough to generate the thermonuclear fusion of hydrogen and helium that powers real stars. Planets do none of that.

"It has puzzled us; we're not sure where to draw the boundary between planets and brown dwarfs," said Hans Deeg, an astronomer at the Instituto de Astrofisica de Canarias (IAC) in the Canary Islands, Spain.

The object has a mass 20 times greater than that of Jupiter, but is roughly the same size. It falls outside the range of planets and stars discovered to date, with the largest planets having 12-Jupiter-mass and the smallest stars 70-Jupiter-mass.

If astronomers confirm the object as a planet, it would weigh in as the most massive and densest planet found so far. A full study will be detailed in the journal Astronomy and Astrophysics.

"COROT-exo-3b might turn out to be a rare object found by sheer luck", said Francois Bouchy, an astronomer at the Institut d'Astrophysique in Paris. "But it might just be a member of a new-found family of very massive planets that encircle stars more massive than our sun. We're now beginning to think that the more massive the star, the more massive the planet."

Ground-based telescopes around the world helped pinpoint the object, including observatories in France, Chile, Germany, Hawaii, Israel and Spain's Canary Islands.

The hunt for exoplanets has intensified over recent years, with astronomers usually finding such objects indirectly by observing their gravitational influence on parent stars. Another team showcased what might be the first direct image of an exoplanet around a sun-like star in September.

Interesting read. Thanks.

I have often wondered if there could be planets the size of Jupitor or bigger that could have Earth like gravity or less.

Nice post Cricket...

Fen....I agree with you there....this falls into the "the universe never fails to amaze me" category!!

thanks cricket

Wow,

If human life were sustainable there, the people would be HUGE. lol

Not to mention toasty. That must be a pretty warm place.

My guess? Brown dwarf. The gravitational forces of the larger star may be what's keeping the dwarf from starting the nuclear chain reactions. It might have something to do with how they formed, something unlike other binaries in which both stars do achieve simultaneous reactions.

No Planet can’t have more than 10^54 atoms. Beyond this limit, gravitation definitively dominates electromagnetism. For its matter to be organized into complex and mobile separate structures, a Planet must have a cohesion that originates in electromagnetism; gravitational force playing a secondary role. A Planet can’t be too large, and its number of atoms must remain < than the critical number approximately equal to the ratio between the intensity of magnetic force and the gravitational force in an atom to the 3/2 power. This ratio is arrived at by comparing the two liaison energies. End of 'Astrophysics 101'...

I havent taken that yet,

That's very interesting

Yes, but is not the weight of an atom determined by the amount of protons.
The atoms are different from element to element.
If a planet did not have any heavy elements than it should be able to be larger than one than is loaded with heavy elements...correct?

Ali… Do you have a reference for the assertion that a planet cannot have more than 10 to the 54th power (10^54) atoms?

As far as I know, there are about 1.33x10^50 atoms making up planet Earth and the Earth is not that large of a planet… ~rore

A reference? Well, any book on astrophysics will do. For instance:
Méthodes de l’Astrophysique, by L. Gougenheim, CNRS Editions.
See also R. Lehoucq who’s astrophysicist, works at the CEA at Saclay and gives courses at the ENS and Polytechnique Schools in Paris.
Planet Earth is made up of about 1.33x10^50 atoms, you say. Thus well below the 10^54 atoms limit, and that’s perfect because that way the Earth deserves to be called a Planet. To qualify as a Planet a celestial body must retain the gaseous molecules near its surface (in other words it must have an atmosphere). To do that, it has to be massive enough. Translated in an equation, it is equivalent to say: The number of atoms of a Planet must be large enough (> than the critical number I mentioned in my previous post), that is approximately 10^54 atoms (without exceeding it).

Ali posts: Planet Earth is made up of about 1.33x10^50 atoms, you say.

Rore posts: It’s not like I pulled that number out of the air Ali…
Here’s a reference: http://education.jlab.org/qa/mathatom_05.html
“We can get an estimate of the number of atoms in the earth by first knowing what its mass is. The mass of an object is a measure of how much material the object has. The mass of the earth is 5.98*1027 grams.
Below is a table that shows the breakdown of the fractional amount of the earth for the most abundant types of atoms (also called the element).
Some of these values are estimates since we really don't know exactly what the center of the earth is made of but scientists have pretty good theories about it. In the table is also a list of how many grams a mole of an element weighs.
The bottom line is that there are about 1.33x10^50 atoms in the world.
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Ali posts: Thus well below the 10^54 atoms limit, and that’s perfect because that way the Earth deserves to be called a Planet.

Rore posts: Then what happens to the figure 10^54 atoms when an Earthlike Planet is discovered to be 3 times the size (mass) of the Earth?
You do know, astrophysicists do think that an Earthlike Planet up to 5 times the size of Earth mass is very feasible?

You see? The assertion no planet can have more than 10^54 atoms seems to fall apart.

If you are unable to provide a link for your assertion Ali, I’ll understand… ~rore

Ok, here’s a reference…
A typical star weighs about 2x10^33 Grams, which is about 1x10^57 atoms of hydrogen per star... http://www.madsci.org/posts/archives/oct98...33072.As.r.html

So what you are implying is that a celestial body of more than 10^54 will fall into the range of a brown dwarf etc… ok… ~rore

The assertion no planet can have more than 10^54 atoms seems to fall apart.
Then Roland Lehoucq, and colleagues, (astrophysicist at the CEA in Saclay) got it plain wrong: For life as we know it on Earth may develop itself, a Planet must have a number of atoms equalling about 10^54. This value corresponds to a big planet, whose mass is comprised between the mass of Earth and that of Jupiter. (See: R. Lehoucq, J.-M. Courty, et al., CNRS, 102, p.240, 2003).

Ali posts: For life as we know it on Earth may develop itself

Rore posts: That wasn't the contention Ali.

We were talking about planet size I.e. What constitutes a Planet.

In my post # 11, I was asking for a linked reference to your assertion that NO planet can have more than 10^54 atoms.
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Ali posts: This value (10^54) corresponds to a big planet, whose mass is comprised between the mass of Earth and that of Jupiter.

Rore posts: Does this mean a planet could be as big as 10^55 atoms?

How big can a planet get before it is no longer considered a planet? (Something greater than 15 Jupiter masses maybe?)
As I mentioned in my post #14, the ‘average’ star is 10^57 hydrogen atoms.

Remember what you said Ali: “No Planet can’t (can?) have more than 10^54 atoms.”
Is that because any body greater than that will cease to be called a planet or what? ~rore

I realize my mistake LOL Thanks rore for pointing it out. Cuiusvis hominis est errare