This is the last thing I expected, we live in an amazing age of discovery. From the AAAS:
Astrophysicist Takahiro Sumi of Osaka University in Japan and colleagues—who form the Microlensing Observations in Astrophysics (MOA) and the Optical Gravitational Lensing Experiment (OGLE) collaborations—now appear to have figured out what is what. In a paper published online today in Nature, the researchers list 10 objects in our galaxy that are very likely to be free-floating planets. What’s more, they claim that in our galaxy, free-floaters are probably so populous that they outnumber stars.
Full story here
So that is what dark matter looks like.
I don’t know why I even try to teach science, as it always changes and the ancillary materials I have are constantly out of date–like the reading I have for them about extra-solar planets (which is actually on the CA Earth Science standards). English teachers just don’t have these problems. 🙂
Ah yes ‘Waifs and Strays’.
Well what goes around comes around. A long time ago I studied under Hoyle, he of the steady state universe, where this topic was of some importance to his theory but of course back then it was supposition since there was no means of observing such a thing.
How important it was to his steady state universe I have never been quite sure since he threw me out fairly early on in my studies for being a big bang heretic and I ended up having to go to the other shop.
Plus ca change etc.
Still absolutely fascinating that we can can now see things we could only speculate upon back then. What these new observations might mean is entirely beyond me.
Kindest Regards
don’t you ever believe any hype. these are likely to be Jupiters orbiting far from the parent stars. the dynamics of expelling planets from a system is daunting to say the least.
@Jenn, actually, English teachers have to be on the cutting edge of painfully awkward gender-neutral neologisms, deconstructionist arguments that prove what is written is thee opposite of what is meant, and the ever accelerating treadmill of euphemisms, or else they shall be branded haters, apostates, and right-wingers.
Let’s suppose there is a supernova, and that there are some loose big planets in the neighborhood, say around a lightyear further away (or whatever distance is required) – this supernova should light them up as though by a nearby star, though only for a short while. So if we carefully examine the area around a supernova for several months to several years later we may notice some bright small objects appear after the supernova has faded, because the light from the lit-up planets shows up a little later due to the longer path to us.
No one really likes a floater…
This is like driving down a country road at night and learning there may be a redneck moonshiner coming the other way in a truck with his lights off.
This actually makes sense. The orbits of planets in our solar system appear to be chaotic over the long term.
I remember a paper discussing the problems of modeling planetary orbits using first principles over long periods of time–millions or billions of years. Either the planets spiral into their star or they slowly drift away and leave the planetary system. To prevent these occurrences, a damping factor has to be added to stabilize the orbits.
Sometimes two planets will interact resulting in one of the planets being ejected entirely.
What surprises me is that they are estimating two rogue planets for every visible star. That’s a lot of rogue planets in the galaxy.
Jim
These planets were found by brightening of background starlight by the gravitational lensing effect. My thought would be that dark objects in inter-stellar space would darken the night sky by blocking starlight. Does this lensing effect mean that whenever they would ‘block’ starlight, they actually collect more of it from a wider area and focus it on us to produce a brighter sky? That is a hard idea to accept. Let’s suppose there is a solar-system sized volume containing the mass of one jupiter in uniformly scattered dust – would it have the same gravitational lensing effect as a single planet of that mass, or is the lensing effect over an area smaller than a solar system? I would expect density might be as important as mass in space bending, but I am not sure at all.
AdderW says:
May 19, 2011 at 11:32 pm
No one really likes a floater…
But the rest of us are flush with excitement!!
And we’ve been worrying about asteroid strike.
One of these on a collision course, that really is Flash Gordon territory.
Here’s a picture of one: http://www.flickr.com/photos/28221085@N03/3499194073/
They have been searching for the ‘extra’ mass that should be in the universe for years and called it ‘ dark matter’ … maybe these are part of it???
@Timebandit – not by a long shot.
jorgekafkazar says:
“This is like driving down a country road at night and learning there may be a redneck moonshiner coming the other way in a truck with his lights off.”
Yes, this wrecks my dreams of accelerating to 3% of light speed to get to the nearest stars. While you’re cruising along @5580 miles per second… BAM!
AdderW said @ur momisugly May 19, 2011 at 11:32 pm
“No one really likes a floater…”
In South Australia they eat ’em. Meat pie floating in pea soup with a large dollop of tomato sauce (ketchup) on top. Never could come at eating one, but I used to dip my chips (fries) in mushy peas in UKLand too many years ago…
I wonder what Velikovsky might have done with the thought that there might be a couple of solar system’s worth of planets just floating around in the relatively near vicinity. Would these worlds be ‘loosely’ in far orbit around the solar system. Would they be relatively stable in galactic orbits but not connected to the solar system? Would they just be randomly moving about – different speeds, different directions?
Talk about extinction catastrophes that might not leave a trace – a Jupiter size planet hitting the sun would almost ceratinly cause life disrupting, if not like ending solar explosions and flares. And I doubt it would come out the other
They aren’t planets; they are just coagulations of lost e-mails.
I can see it now: some holywood script writer having torn up his “the world is going to end when it gets a little bit warmer (maybe) disaster script” is gleefully starting a new script:
deep in dark space, travelling eons lost in the Universe a frozen planet of Aliens are heading this way …
Watch for the Planet X groupies latching onto this discovery. They have “predicted” that 2012 will mark the return of the wandering Planet X which will end civilisatiion on Earth. Apparently the government is covering up the approach because they dont want us to panic LOL this article will be fuel to their fire….
Oh no!!!! The extra manmade CO2 is going to destabilize our orbit, & we’ll be lost in space for ever, oh no, oh no, oh no………..Give them time peeps.
I don’t think somehow, given the “mass” of the universe, a few zillion large homeless planets are going to provide the hidden “mass” that people speak of. My usual thoughts are if someone has done a calculation & things don’t add up, the sums are probably wrong in the first place. Besides, another theory is waiting in the wings, there always is! Next.
Our ability to detect such things seems to continue to improve and long may this continue.
Isn’t Earth moving away from the Sun?
http://www.newscientist.com/article/dn17228-why-is-the-earth-moving-away-from-the-sun.html
Isn’t our moon moving away also?
http://www.bbc.co.uk/news/science-environment-12311119
I don’t know why this is surprising. People are always telling me that if the earth moved any faster it would be flung out into space and any slower it would fall into the sun. Usually they use this as a reason for believing in God (let’s not start a religious argument here), but to me it meant that most likely there were thousands of planets orbiting the sun shortly after the big bang and now that all of them dropped into the sun or have been flung out into space we only see nine left. The planets we are discovering now are just the ones that moved to fast to stay around the sun. The only surprising thing is that we already have the technology to find them.