New planets forming elsewhere

[TransformerRobot]

Is there a chance of new planets still forming far away in space, even at this very time?

[ACG52]

Is there a chance of new planets still forming far away in space, even at this very time?

 

 

Oh yes. Star formation goes on, and certainly planet formation follows.

[Spyman]

 

Protoplanetary Disks Seeen in Projection

 

Above are Hubble Space Telescope images by Mark McCaughrean and Bob O'Dell, taken towards the Orion star formation region. Seen in silhouette against the background luminous gas are several elliptical objects with length scales of 100's to 1000's of AU. They are most likely protoplanetary disks. The central bright spot (easily seen in the lower right panel) is light from the protostar leaking out through the disk. The opacity in the disks is due to dust. It is nice to think that the dust in these systems is sticking to grow into pebbles and planetesimals. We know from observations of other young stars that this process of accumulation happens within a few million years of the formation of the disk. Eventually, the dust will be trapped inside macroscopic bodies like comets and planets.

 

Last updated December 1997 by David Jewitt

http://www2.ess.ucla.edu/~jewitt/Origins-proplyds.html

 

Also more reading about star/planet formation here: Nebular hypothesis

[Ophiolite]

Is there a chance of new planets still forming far away in space, even at this very time?

Here is a back of the envelope calculation, but it should give within an order of magnitude of the correct answer.

 

Star formation rate in the galaxy is 7 stars per year. (Source:http://phys.org/news9595.html)

 

Formation time for the planets is around 50 million years (Ranging from 10 million to 100 million)

 

Assume five planets per system as the norm

 

Total number of planets now forming in the galaxy equals 7 x 5 x 50,000,000 = 1,750,000,000

[CaptainPanic]

Nice calculation, Ophiolite! 7 stars per year and 5 planets per star means 35 planets per year (or about one every 10 days!). That's a nice and tangible number. I love this kind of back-of-the-envelope calculations.

 

Could it be that there are also planets forming away from a forming star? Could it be that interstellar gas/dust gathers to form a planet that does not have a star?

Maybe I should ask: is there such a thing as interstellar material? And is that abundant enough to create a planet?

[Klaynos]

Could it be that there are also planets forming away from a forming star? Could it be that interstellar gas/dust gathers to form a planet that does not have a star?

Maybe I should ask: is there such a thing as interstellar material? And is that abundant enough to create a planet?

 

(I've actually been lectured on this by one of the people whose name appears on the bottom of the picture! My claim to fame I guess)

 

But to answer your question that really depends on your definition of planet. Yes, star forming regions create entities which are too small to even to fuse deuterium, these are sometimes termed giant planets, sometimes brown dwarfs, and I seem to recall there are a couple of other terms I cannot remember. It is possible that they have a composition close to that of Jupiter but I suspect they'd have less heavy elements.

 

Personally I wouldn't call them planets, they form in a different way and are not in a solar system...

 

Outside star forming regions I do not think you could have a mass density large enough to form anything of note.

[Airbrush]

The new issue of Astronomy magazine has an article about planets that get thrown out of solar systems and are wondering around the galaxy. They are estimated to be many more than the number of stars in the galaxy. Young solar systems are thought to have many planets that either crash together, or get thrown out by gravitational interactions.