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Strange New 'Twin' Worlds Found
toomanyairmiles writes "The BBC reports on the the discovery of 'twin worlds' which orbit each other, successfully blurring the line between planets and stars. 'Their existence challenges current theories about the formation of planets and stars.' according to the Journal of Science article which reports their existence. 'The pair belongs to what some astronomers believe is a new class of planet-like objects floating through space; so-called planetary mass objects, or "planemos", which are not bound to stars.'"
However insular we want to be, the universe has all sorts of stuff in it that we would never expect. Sure with CGI, we can 'visit' anything we can imagine.
It's just great that there is more than that out there. Gives me hope for the future.
Rhymes that keep their secrets will unfold behind the clouds.There upon the rainbow is the answer to a neverending story
It's a space station!
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Stars can only 'ignite' when enough mass accumulates. It would make sense that often there would be chunks of smaller mass just floating around until they scoop up enough matter into their gravity well to start fusion.
I think we can just stick to "The twins"...
Anticipating a possible question: no, a previously-unknown population of "planemos" can't be the dark matter astronomers are searching for. First, there were enough of them to account for the huge mass of dark matter (some 95 percent of the mass of the universe), we would have seen a lot more of them by now. "Massive compact halo objects", or basically planetoids, brown dwarfs, neutron stars, etc. have been detected (via gravitational lensing), but they are known not to comprise the majority of dark matter due to such bounds on their total mass. Furthermore, from the effects of dark matter on structure formation in the early universe, the cosmic background radiation, and other factors, it is known that "normal" matter can't account for most of the mass of dark matter, either: most of it needs to be in the form of "weakly interactive massive particles" (sort of analogous to neutrinos, except much heavier).
"The pair belongs to what some astronomers believe is a new class of planet-like objects floating through space; so-called planetary mass objects, or "planemos", which are not bound to stars.'"
Once again proving that astronomers should not be naming things while drunk. Here's a handy reminder: "Remember the Planemos!"
Vincent J. Murphy
Spandex Justice
Ok so our Solar System is mostly flat. I mean, the orbits of the planets tend to follow the same orbital plane, with a notable exception of course.
The reason the planets orbit in the same plane is the same reason rings around celestial bodies like Saturn eventually fall into a common orbital plane: gravity. As the mass collects there is something like a gyroscopic effect, causing a general influence towards the common plane.
But.. if that's the case, why do we have a planet that doesn't follow the plane? And, also, is it slowly falling into line with the rest? (I think the answer is yes, it is, but I don't know for sure.. at least I think it should be).
Which leads me to ask.. Was Pluto originally extra-solar? Could it have developed in this eccentric orbit if it were originally part of the solar system when it formed? Is it possible that Pluto somehow, amongst the billions of years our system has been around, floated into orbit here for good, from Out There?
And if so, if there are enough of these free-floating masses out there, what kind of percentage of the unobservable 'dark matter' might this account for?
Just a few of my questions,
TLF
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"Yes, it's really easy to confuse a ball of rock with a star. I mean, the similarities are so obvious."
In terms of such stars as Ben Affleck, the similarities do start to build up.
Where were you when the voynix came?
Which one is the evil twin?
Thank you , I'll be here all evening!
how long until
Snakes, on a PLANEMO????
Where were you when the voynix came?
technically they do... a planetary object by definition needs something to orbit.
What i think you meen is that a nebula of the right size can form a stelar object that doesnt have the mass for fusion.
Six times the distance from the Sun to Pluto. If you're on one planet you might be lucky to see the tiny dot of the other planet in the night's sky... I don't recall if it said they were orbiting a star (for light) or not. So even the picture is misleading.
They both orbit around their common center of mass, as do all pairs of orbiting bodies. The moon and earth actually orbit around a point 4700km from the earths center.
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