Lonely Planets

[Fenderman]

http://www.newscientist.com/article...onely-planet-roams-with-stellar-outcasts.html

Came across this in New Scientist magazine. Since the discovery of the first planets around other solar sytems planet hunting is really gathering pace. Now a large planet has been found roaming through space having broken free ot its solar system. It is estimated to be an age range of between 50 and 120 million years and somewhere between 4 to 7 times the mass of Jupiter. The scientists discovered this "rogue planet" whilst surveying brown dwarfs in a string of objects moving through space in the same direction. They reckon it's too small to be a brown dwarf.and think its temperature is around 400 °C which, if I read the article correctly, would be quite warm or a dwarf star. One of the discoverers, Philippe Delorme, says it's easier for smaller planets to break free of their solar systems so there may be a lot of frozen Earth-like planets drifting through space.

Makes ya think, don't it?


By the way does anyone want my NS collection dating back to about 1976? Second thoughts, I'll keep it you never know when the next good argument will crop up.

 

[Greenlantern101]

You have 36 years of New Scientist magazines ???????? Isn't that weekly .... hang on ...... 1872 mags.

Do you live in a warehouse or are you one of these odd ball horders that live in a broom cupboard because the rest of the house is full of junk

 

[gethinceri]

That's why I built up such a stack of printed pornography, they all got published monthly. No PhD and I could never wear an automatic watch for fear of overwinding.

 

[Fenderman]

Greenlantern101 I haven't bought it as regularly in recent years but, yup, I've got rather a lot of them. It's a good job the magazine isn't as bulky as Motorsport or F1 Racing, otherwise I'd really be in trouble! Thankfully, I now read more or less what I'm interested in on the NS website. Saves space and money!

Edit: Oh, yes, and my house is full of stuff. Books (mostly non-fiction and Sci Fi), Mag's (scientific, motor and motorcycle sport), Vinyl LP's, ludicrous number of plastic and die-cast models (built from kits), musical instruments, gadgets, etc. etc. I have no pension so I'll open a junl shop when I'm forced to retire and flog it all off. Should get by for about a month.

gethinceri - . Haven't kept the porn. I think I've missed a trick!

 

[Incubus]

It is thought that are actually more rogue planets in our galaxy than stars, and it's easy to imagine why. They reflet no light from any parent star so they are incredibly hard to detect. The early stages of star system formation have very irregular patterns before newly-formed planets begin to gain regular stable orbits, and a many of these get thrown out of orbit during the gravitational tug-of-war of early star-system formation. Our own solar system is said to have probably lost several newly-formed planets in its early stages.

 

[FB]

If said planet roamed close to another star wouldn't it take up an orbit around that star? I presume it has to wander close enough to a star with enough gravitational pull?

 

[Fenderman]

Almost answered your own question there FB. If the rogue planet isn't travelling too fast when arriving in another solar system one would expect it's capture by another star or even to fall within the influence of a larger planet to be possible. The circumstances would have to be just right for a stable orbit to result, though, needing the ideal trajectory and velocity. Too fast and it will fly right by. Too slow and too close and the gravitational attraction between the it and the star would probably result in the star swallowing the planet. Maybe one day our astronomers will observe just such an event.

 

[Incubus]

Rogue planets don't exactly "roam" randomly around. Once free of the gravititonal influence from their old parent star they begin orbiting around the centre of the galaxy, along with stars, in the same direction and at the same relative speed. It isn't well understood why that is but stars orbiting furthest from the galaxy's centre do so at the same relative speed as stars orbiting nearer... and so so rogue planets. That is why the distance between stars remain at fairly constant distance from each other, and the same goes for rogue planets. That makes it much more likely that rogue planets... will remain that way.