Newly Discovered Object Revives Speculation of Planet X.

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Newly Discovered Object Revives Speculation of Planet X.

Is the "Planet X" suggestion back again ?  and could there be proof yet to come ? 


The likely-dwarf planet adds to the mounting evidence of a dark super Earth at the outer boundary of our solar system.



?Move aside, Sedna and 2012 VP113. There's a new most distant object in our solar system, and it strengthens the hypothetical case for an unseen large planet at the outer boundaries of our solar system.

The object, V774104?, was announced today at the American Astronomical Society's Division for Planetary Sciences meeting in National Harbor, Maryland. Scott Sheppard of the Carnegie Institute characterized the potential planet as between 300 and 600 miles in diameter, on par with a medium-sized moon. This makes it a likely dwarf planet, as it's roughly the size of Ceres in the Asteroid Belt.


At 103 astronomical units out (or 103 times the distance of the sun to the Earth), this is the most distant object ever recorded, besting Eris, Sedna, and 2012 VP113. It also adds on to a case built on the discovery of the latter, whose unusual orbit points to the tug of a distant planetary-mass object. Though previous surveys have ruled out anything above the size of Saturn, there still could be a Neptune-sized world or a super-Earth (or even two) farther out, too dark and distant to detect. For now, though, this is just speculation that can't be ruled out. There's also the possibility that the objects were tugged into their present orbits by a passing star around the time of the formation of the solar system.

V774104 may be part of the Inner Oort Cloud, a region farther out than the Kuiper Belt where Pluto and Eris live. It's where most long-period comets are believed to have originated. A dozen smaller objects were discovered along with the new object, but little else is known of it, including its orbit. It could be oblong, like that of Sedna, another Inner Oort Cloud object. That one comes as close as 86 AU and goes as far out as 937 AU, giving it one of the strangest orbits in our solar system.

If this newly discovered object ends up being an Inner Oort Cloud object, it could prove valuable in helping astronomers understand the solar system. Sheppard and co-author Chadwick Trujillo plan on studying the object in more detail to correctly determine its orbit. Trujillo already has a few new objects under his belt, having co-discovered Eris and two other dwarf planets, Makemake and Haumea, as well as Sedna.

http://www.popularmechanics.com/space/news/a18144/v774104-furthest-object-in-solar-system/

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Astronomers Find the Farthest-Out Solar System Object Ever Seen
More than a hundred times as distant from the Sun as Earth is, the object could be a pristine remnant from the primordial solar system


Astronomers have spotted the most distant object ever seen in the Solar System:

a frigid world that currently lies 103 times as far from the Sun as Earth is. It breaks a record previously held by the dwarf planet Eris, which had been seen at 90 times the Earth-Sun distance.



Scott Sheppard, an astronomer at the Carnegie Institution for Science in Washington DC, reported the object on November 10 at the American Astronomical Society's Division for Planetary Sciences meeting in National Harbor, Maryland.

The object's extreme perch—beyond the edge of the Kuiper belt (home to Eris and Pluto) and into the inner fringes of the next part of the Solar System, known as the Oort cloud—suggests that it could be of scientific significance. Bodies in this primordial realm travel orbits that have remained undisturbed for billions of years.

But astronomers have not tracked the 103 AU object long enough to know its full path, and there is a chance that it will travel much closer to the Sun than it is currently. That would make it less interesting to astronomers.

"There's no reason to be excited yet," says Michael Brown, a planetary scientist at the California Institute of Technology in Pasadena. "I'd be willing to bet it has some more mundane explanation."

The long view
Still, the object's discovery gives a rare glimpse at the fringes of the Solar System. Only two worlds are known in the inner Oort cloud: an object called Sedna, discovered by Brown and his colleagues, and another one known as 2012 VP113, popularly nicknamed 'Biden' and discovered by Sheppard and Chadwick Trujillo of Gemini Observatory in Hilo, Hawaii.

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Sedna never gets closer to the Sun than 76 AU; VP113's closest approach is 80 AU. If 103 AU is just about as close as the newfound world ever gets to the Sun, it will join the other two objects as a scientifically fascinating resident of the inner Oort cloud.

But if the 103 AU object moves closer to the Sun, past the outer edge of the Kuiper belt at about 50 AU, it will join the ranks of many other, more mundane Kuiper belt denizens whose orbits are particularly stretched-out because of the gravitational influence of the planet Neptune.

Inner Oort cloud objects are more intriguing than Kuiper belt objects because they lie too far away from Neptune to have ever been influenced by its pull, says Sheppard. Instead, their orbits likely reflect primordial conditions in the Solar System, which formed more than 4.5 billion years ago — making them tantalizing targets for astronomers.

Sheppard and Trujillo discovered the 103 AU object using the Subaru telescope atop Mauna Kea, Hawaii. The body is probably well over 500 kilometres—perhaps 800 kilometres—across. The researchers plan to look for the object again next week using the Magellan telescopes in Chile, and then again in a year to calculate its orbit and learn whether it is a true inner Oort cloud object.


http://www.scientificamerican.com/article/astronomers-find-the-farthest-out-solar-system-object-ever-seen/


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Most distant solar system object yet could hint at hidden planet.




The inky black of the outer solar system just got a little brighter. A speck of light spotted in October 2015 is a rocky world more than 3 times more distant than Pluto – the farthest body in our solar system ever seen.

"We don't know anything about its orbit," says Scott Sheppard of the Carnegie Institute of Washington, whose team discovered the new addition. "We just know it's the most distant object known."

Sheppard announced the new object, called V774104, on 10 November at a meeting of the American Astronomical Society's Division for Planetary Sciences, held in National Harbor, Maryland.

From how it shifted in the sky as the Earth moved over a few hours, Sheppard's team calculates that V774104 is about 103 astronomical units (AU) away from the sun, where one AU is the distance from Earth to the sun. That's about as far away as the twin Pioneer probes, which have been traveling since 1972 and 1973.


To be as bright as it is at that distance, the object needs to be between 500 and 1000 kilometres in diameter, less than half the size of Pluto.

And it's not alone. The same deep sky survey, conducted with the Subaru telescope in Hawaii and the Dark Energy Survey Camera in Chile, has also turned up about a dozen other objects around 80 to 90 AU from the sun. Since these distant bodies move around the sky slowly, it will take about a year of follow up observations to understand their orbits – and their origins.

If it turns out their paths will take them inward near Neptune's orbit, they were probably kicked out of the inner solar system after a brush with Neptune. But Sheppard hopes that some will turn out to belong to a class of true weirdos: the inner Oort Cloud.

Dark planet
Only two other known objects are thought to be members of this exclusive club: Sedna, discovered in 2003, and 2012 VP113, found in 2012. Neither of them ever comes closer to the sun than 50 AU. The rest of the Oort Cloud, which is thought to be a storage lot for long-period comets, extends out a hundred or even a thousand times farther than these objects.

"Sedna and VP113 are the only object in the known solar system whose orbits cannot be explained by things in the known solar system," says Michael Brown of the California Institute of Technology. They are far enough away from the giant planets to avoid gravitational tweaks to their orbits, and close enough to the sun that they don't respond to other passing stars.

One explanation for the strange orbits is the pull of a massive but very dark rocky planet. "Something might be shepherding the objects," Sheppard says.

But the more likely explanation, according to Sheppard and Brown, is that the inner Oort Cloud preserves signs of an era at the very start of the solar system, when the sun and planets were born in an interstellar nursery packed tightly with nearby stars.

Over the next year, monitoring the new candidate objects may uncover a rare few that never venture into the inner solar system. If so, their orbits, added to Sedna and VP 113, should help us understand what influences such far-out worlds. Meanwhile, we have to wait to see what becomes of V774104.

"You don't know whether it's just a gee-whiz record holder or something super cool," Brown says. "I've got my fingers crossed for super cool."



http://www.scientificamerican.com/sciam/cache/file/764FDBB5-982F-4848-A25CBC81B2BFCF27_article.jpg?C35A9