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What's nudging comets our way? Every so often a comet gets flung out of the Oort Cloud, a swarm of comets on the fringes of the solar system, and gets close enough to Earth for us to see it. But they don't seem to be scattered at random.
“There's an abundance of them around a great circle in the sky, and that suggests that there's something perturbing them in from this great circle.”
Jack Lissauer of NASA's Ames Research Center at the American Astronomical Society meeting in Boston. Lissauer and his colleagues have long suspected a planet-size object, sometimes called Tyche, could be hiding in the Oort Cloud.
“The model that is the simplest explanation for this is that there's a perturber in the Oort Cloud, and calculations suggest this would have to be Jupiter mass, maybe a few times the mass of Jupiter.”
A NASA spacecraft called WISE may well be able to see it. But only if Tyche isn't at the low end of its hypothetical mass range. And, of course, only if Tyche is real.
—John Matson
[The above text is an exact transcript of this podcast.]
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20 Comments
Add CommentVery interesting, although it would be nice to know how something the size (and presumably mass) of Jupiter could avoid detection, even at the outer reaches of our solar system, especially if we can now detect other planets around other stars light years away.
Reply | Report Abuse | Link to thisMing_on_mongo,
Reply | Report Abuse | Link to thisIt has to do with detection technique. Planets around other stars are detected by their effect on the stars they orbit; by a wobble induced in the star, for example, or by the dimming of the star as the planet passes in front of it. But none of those techniques would work on the theoretical Tyche - and if it's far enough out in the Oort Cloud, it may be all but impossible for even the Hubble to see directly.
I think it's Oort himself who is flinging the comets. We must have pissed him off or something.
Reply | Report Abuse | Link to thisBelow are three very informative links about this matter:
Reply | Report Abuse | Link to thishttp://solarsystem.nasa.gov/planets/profile.cfm?Object=KBOs&Display=OverviewLong
http://www.space.com/53-comets-formation-discovery-and-exploration.html
http://www.space.com/56-our-solar-system-facts-formation-and-discovery.html
I suspect the reason these comets seem to get flung toward our planet, is that Jupiter is somehow acting as a gravitational "lens" that is coincidentally "focused" in our direction.
Reply | Report Abuse | Link to thisI seriously doubt there is intelligence flinging these comets toward us, like the insect-like intelligent lifeforms in the movie "Starship Troopers" (1997) caused asteroids in an asteroid belt to get flung toward Earth in an attempt to wipe out our species.
We can detect planets orbiting other stars, yes, but only if they are VERY close in or quite large. A Jupiter mass object far out in the Oort Cloud of another system would be undetectable.
Reply | Report Abuse | Link to thisRemember, the Oort cloud is WAY out there, the INNER Oort cloud starts at around 1,000 AU and it may extend out as far as 100k AU (between 1 and 2 light years, halfway to the next star). At that distance a Jupiter mass object's direct gravitational effect on even the outer planets would be insignificant, and its effect on the proper motion of the Sun equally negligible. In principle 100 Jupiter mass objects could float around out there and we would be none the wiser.
Truthfully we know very little about the regions of space out there. It is a vast dark region.
I believe it's very likely there are large planets or even mini-solar system(s) of planets out there in the Oort Cloud orbiting the sun. Their period is so long that they are undetectable by their gravitational effect on the inner planets. Because they are too small to "ignite" [start nuclear fusion] they can't be seen in visible, and are too far from the sun and other stars to be seen in reflected visible light.
Reply | Report Abuse | Link to thisI don't know if infrared telescopes are good enough to pick up Jupiter-sized planets at a range equivalent to 1/3 of the way to the nearest visible star. [I believe that would be Barnard's Star @ about 4 light years].
If you look at a "mass spectrum" of known objects in the Milky Way I think you'll find an anomaly in the medium sizes. There's plenty of gas and dust as estimated from the glow around super novas and such, and there's a more certain estimation of the mass of stars in the galaxy. But total mass of planet-sized objects, which reflect and emit very little radiation per unit of mass, is probably vastly underestimated.
This theory would succinctly explain the anomalous shape of the revolution of stars around the centers of galaxies. The distribution of the visible stars in galaxies would require the extremes of the arms to be revolving much slower, relative to the central region, than is observed. An explanation would be that the extremes of galaxies and beyond are much more densely populated with planet sized objects. So, this "missing mass" is actually just lots of ordinary matter that is, so far, undetectable by any means other than it's gravity.
Back to our own solar system: Perhaps the only means to detect planet sized objects in the Oort Cloud is by occultations of distant stars. Such occultations would be very quick when they occur and very rare. To detect and record them would require constant vigilance of millions of stars over many years with hundreds of telescopes. Some day it will be done. Then the realization of so much mid-sized missing mass within the extremes of the solar system will add credence to the theory of similar missing, mid-sized mass within the extremes of galaxies. Then these silly theories of "dark matter" and "dark energy" can be relegated to the "dustbin of history".
That's a good theory, however if I'm not mistaken, current calculations predict that dark matter makes up the majority of the universe, so even if there were thousands of jupiter sized objects floating around undetected on the fringes of every solar system, I still don't think that would be enough mass to even get close to the theoretical amount of dark matter, or missing mass in the universe. however, if there were that many jupiter sized objects floating around, it could be a good start to explaing SOME of the missing mass in the universe
Reply | Report Abuse | Link to thisI wish I could find a good study on the distribution of mass in the universe. But my contention is that the knowledge of mass distribution is very incomplete. I have a hard time with this "dark matter / dark energy" theory, so:
Reply | Report Abuse | Link to thisIf somebody with lots of time and lots of access to data would make a graph with size of objects [from molecules to biggest stars] on Y axis and total mass of known objects at that size on the X axis, in some sector of space [our arm of the milky way, our galaxy or our galaxy cluster], they would probably that find the graph doesn't form a natural curve. There's bound to be BIG gaps in the curve. Firstly dust and gas clouds can only be detected when bright stars are in it, so some extrapolation must be make for total dust/gas. Total mass of stars doesn't need to be guessed. But planet sized objects have relatively large mass to surface ratio, and the surface is what is reflective or radiative. So I suspect that such a graph would be double humped because the total mass of mid-sized objects is vastly underestimated.
I don't know what the size distribution of stars in the milky way is relative to distance from the center, but if there's a trend of smaller stars at the extremities, it stands to reason that there's probably lots of mid-sized mass beyond the visible galaxy.
The reason we don't encounter planet sized objects very ofter [or at all] in the solar system is because they have been "cleared" by the sun in it's path in the local star cluster in just the same way that the major 8 planets have "cleared" their orbital paths by either making them satellites, swallowing them, or by flinging them out of the orbit.
I also doubt the "expansion" of the universe theory. It could be possible that light is red-shifted by repeatedly passing through the gravitational fields of millions of heavy objects. Diffuse "clouds" of small dense objects could somehow sap energy from radiation passing through without noticeably "lensing" it. I read in Einsteins' book on relativity that this effect should happen. I'm sure good astronomers have thought of that, but perhaps couldn't assume the right amount of intervening mass.
Reply | Report Abuse | Link to thisIt strikes me as 2 orbits at tangent where they intersect something gets ripped out.
Reply | Report Abuse | Link to thisWhat really strikes me as odd is the concept of a large body doing this rather than swallowing the many objects in its wake.
Id say its something small, producing a convenient hat trick of coincidences before a rock comes in our direction.
The mistake of Astronomers about comets:
Reply | Report Abuse | Link to thisComets do not come from the Oort cloud, but they are fire masses emitted out of the sun (like big sparks) following some explosions there.
The comet does not include any dirty ice; it is part of the hot sun substance, which do not circle around the sun, but roam in the space.
They are attracted to the cold regions of the planets and moons, like the polar region of the Earth, Canada and Siberia.
When the flaming comet falls down, it digs the surface of the earth to bury under the ground, leaving a crater.
<http://www.quran-ayat.com/universe/new_page_3.htm#Comets>
I find it to rather interesting that the NASA researchers have chosen to name this hypothetical object Tyche. In the mythology for the Forgotten Realms campaign world of the Dungeons & Dragons game, Tyche is the (now) deceased goddess of random fortune. Tyche perished after one of her random curses got her off guard. From her dead carcass sprang the goddess of good fortune (Tymora) and the goddess of misfortune (Beshaba).
Reply | Report Abuse | Link to thisCould it be that the Oort Cloud is not a cloud but more like a disk?
Reply | Report Abuse | Link to thisComets would then enter the inner solar system, mainly from a great circle in the sky, due to being displaced by random interaction.
Could it be that the Oort Cloud is not a cloud but more like a disk?
Reply | Report Abuse | Link to thisComets would then enter the inner solar system, mainly from a great circle in the sky, due to being displaced by random interaction.
Sedna has a big brother or sister?
Reply | Report Abuse | Link to thiswayyy cool
Although difficult, if not impossible, to spot in visible light - a Jupiter+ would shine quite brightly in infrared. As the referenced paper recognises, we should check IR telescope data (such as WISE) for such an object. The problem is that we've only had such data for a relatively brief period, during which an Oort object would have moved only slightly, making it tricky to differentiate.
Reply | Report Abuse | Link to this@ming_on_mongo you can see it, just not with the naked eye its waay to cold.. And its not a planet.. Its BIGGER.. Check this link out to see it..
Reply | Report Abuse | Link to thishttp://www.google.com/sky/#latitude=13.207860470525487&longitude=-32.047119140625&zoom=6&Spitzer=0.00&ChandraXO=0.00&Galex=0.00&IRAS=100.00&WMAP=0.00&Cassini=0.00&slide=1&mI=-1&oI=-1
Just because your scriptures give a 1,400 year old description of an observed phenomenon doesn't mean that the scripture writer was actually correct. When NASA ran a probe into a comet they didn't find a hot bit of solar matter. They found ice and dust.
Reply | Report Abuse | Link to thisTyche is a male deity of fortune from Greek mythology. The publishers of Forgotten Realms lack imagination and can't come up with their own ideas so they do the typical hollywood "let's steal an idea and name and then pervert it beyond all recognition".
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