Cool Science News of the Week

Jesse Walker | June 8, 2006

From the BBC:

The study...looked at a number of recently identified planemos (an unofficial term sometimes used to describe planetary mass objects).

Located about 450 light-years away in a star-forming region, four of the objects are just a few million years old, making them cosmic "newborns". They have masses between five and 15 times that of Jupiter.

But unlike Jupiter, these objects are floating through space without an accompanying star.

Infrared emission reveals the planemos are circled by dusty discs, which scientists believe could evolve into planets, comets and asteroids over time, in much the same way our own Solar System's planets are believed to have formed billions of years ago.

Whole thing here.

Comments

|6.8.06 @ 11:34AM|#

"They have masses between five and 15 times that of Jupiter."

Which probably isn't big enough to get any nuclear fusion going.

These things sound like fetal stars that haven't yet accumulated enough enough mass to be "born".

|6.8.06 @ 11:41AM|#

Are we sure these aren't really the flottila of Pierson's Puppeteers?

|6.8.06 @ 11:43AM|#

Would the dusty discs shield us from Cylon raiders?

|6.8.06 @ 11:43AM|#

Don't be silly, Sam, they haven't left yet.

I did just spot the Ringworld in my 8" Dobsonian. Wow.

Jeff P|6.8.06 @ 12:28PM|#

I believe the residents of Moonbase Alpha encountered one of these...

|6.8.06 @ 12:34PM|#

OK, I'll take the plunge.

"These things sound like fetal stars that haven't yet accumulated enough enough mass to be "born"."

So the universe still has time to abort it?

|6.8.06 @ 2:16PM|#

Just to be pedantic: these are far short of the mass of the smallest stars -- it takes between 72 and 90 Jupiter masses to ignite hydrogen fusion. These are even too small to be considered brown dwarfs (19-72 Mj) because they're not massive enough to fuse deuterium, which is one criterion for brown dwarfs, as opposed to planets.

The difference between planets and brown dwarfs is MEANT to be that planets form by building an icy core and adding on to it, while brown dwarfs form from a collapsing cloud of gas. These objects, if too small to be typical brown dwarfs, are challenging that definition -- if these formed from collapse, then there may be no line to be drawn between really big planets and really small brown dwarfs at all.

|6.8.06 @ 3:49PM|#

"So the universe still has time to abort it?"

Not in South Dakota or Louisiana. Those planemos have all the rights and protections of full-fledged stars!

|6.8.06 @ 10:57PM|#

"The difference between planets and brown dwarfs is MEANT to be that planets form by building an icy core and adding on to it, while brown dwarfs form from a collapsing cloud of gas. These objects, if too small to be typical brown dwarfs, are challenging that definition -- if these formed from collapse, then there may be no line to be drawn between really big planets and really small brown dwarfs at all."

This, of course, assumes that there is a well defined set of criteria defining a planet. But not yet:

http://news.yahoo.com/s/space/20060608/sc_space/definitionofplanetexpectedinseptember