A planet-size object could be behind the odd departure of some comets from the Oort Cloud--and toward us.
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. Jack Lissauer of NASA's Ames Research Centre 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.Read more
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. Jack Lissauer of NASA's Ames Research Centre 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 argument Matese and his colleague Dan Whitmire have been making since the late 1990s is that some comets seem to be moving in toward the Sun from a skewed direction. They start out in the Oort Cloud, a vast collection of perhaps trillions of small, icy chunks that hover at the very outer edges of the Solar System. Every so often, a passing star or the tidal effect of the Milky Way itself jostles the cloud, sending some of the chunks sunward to light up the night sky as comets.When Matese and Whitmire analysed the orbits of these Oort Cloud comets, about 20% of them seemed to come not from the random directions you'd expect, but from a narrower section of sky. This might suggest a giant planet, at least the size of Jupiter and maybe up to four times as big. Its size would not be its only remarkable feature; it's remote orbit would be another - a tidy trillion miles from the Sun, or more than a thousand times more distant than Pluto.
Two UL Lafayette astrophysicists believe there's something in our solar system that's sending comets toward earth.This NASA graphic shows 'the Oort Cloud,' which surrounds our solar system.It contains billions of comets. Scientists believe there's something four times as big as Jupiter that's pushing some of those comets our way.
Our sun may have a companion that disturbs comets from the edge of the solar system - a giant planet with up to four times the mass of Jupiter, researchers suggest.A NASA space telescope launched last year may soon detect such a stealth companion to our sun, if it actually exists, in the distant icy realm of the comet-birthing Oort cloud, which surrounds our solar system with billions of icy objects.The potential jumbo Jupiter would likely be a world so frigid it is difficult to spot, researchers said. It could be found up to 30,000 astronomical units from the sun. One AU is the distance between the Earth and the sun, about 150 million km.
We present an updated dynamical and statistical analysis of outer Oort cloud cometary evidence suggesting the sun has a wide-binary Jovian mass companion. The results support a conjecture that there exists a companion of mass ~ 1-4 M_Jup orbiting in the innermost region of the outer Oort cloud. Our most restrictive prediction is that the orientation angles of the orbit normal in galactic coordinates are centred on the galactic longitude of the ascending node Omega = 319 degree and the galactic inclination i = 103 degree (or the opposite direction) with an uncertainty in the normal direction subtending ~ 2% of the sky. A Bayesian statistical analysis suggests that the probability of the companion hypothesis is comparable to or greater than the probability of the null hypothesis of a statistical fluke. Such a companion could also have produced the detached Kuiper Belt object Sedna. The putative companion could be easily detected by the recently launched Wide-field Infrared Survey Explorer (WISE).
An invisible star responsible for the extinction of dinosaurs may be circling the Sun and causing comets to bombard the Earth, scientists said.The brown dwarf - up to five times the size of Jupiter - could be to blame for mass extinctions that occur here every 26 million years, The Sun reports.The star - nicknamed Nemesis by Nasa scientists - would be invisible as it only emits infrared light and is incredibly distant.