from the number-9-number-9-number-9 dept.
For the past few years, [Scott] Sheppard of [the Carnegie Institution for Science], [Chadwick] Trujillo [of Northern Arizona University] and David Tholen of the University of Hawaii have been hunting for objects in the far outer solar system using several different instruments, including the Subaru Telescope in Hawaii and the Dark Energy Camera, which is installed on a 4-meter telescope at the Cerro Tololo Inter-American Observatory in Chile. [...] The astronomers discovered several dozen previously unknown bodies, including a roughly 155-mile-wide (250 km) object called [2014 FE72] that gets an incredible 4,000 AU from the sun at its most distant point. That puts it out in the outer Oort Cloud — the realm of comets.
[...] They also discovered two 125-mile-wide (200 km) objects, known as 2014 SR349 and 2013 FT28, that "cluster" in one of the key orbital parameters (known as argument of perihelion), furthering strengthening the case for Planet Nine's existence. (The objects' names reflect the years that they were first spotted in the survey; their discovery is being announced in the new study.) "We have 15 or so of these extreme objects now, and all of them cluster in this argument of perihelion angle," Sheppard said.
Furthermore, he added, the five most distant of these 15 extreme objects share similarities in another orbital characteristic as well, one called longitude of perihelion. Significantly, the far-flung five are too distant to be realistically affected by any gravitational tugs from Neptune (whose influence could be the reason the other 10 objects' longitudes of perihelion don't line up). It would take just two or three more such additional finds to put Planet Nine on solid ground, Sheppard said. "I think statistics-wise, in the next year to two years we'll probably find enough of these small, extreme objects to really say if Planet X exists or not," he said. [...] "We need like 10 or 20 of these smaller extreme objects, and we can probably nail down much better where Planet X would be out there," Sheppard said.
Also at the Carnegie Institution for Science.
NASA is inviting the public to help search for possible undiscovered worlds in the outer reaches of our solar system and in neighboring interstellar space. A new website, called Backyard Worlds: Planet 9, lets everyone participate in the search by viewing brief movies made from images captured by NASA's Wide-field Infrared Survey Explorer (WISE) mission. The movies highlight objects that have gradually moved across the sky.
"There are just over four light-years between Neptune and Proxima Centauri, the nearest star, and much of this vast territory is unexplored," said lead researcher Marc Kuchner, an astrophysicist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "Because there's so little sunlight, even large objects in that region barely shine in visible light. But by looking in the infrared, WISE may have imaged objects we otherwise would have missed."
Previously: No Evidence for 'Planet X', says NASA - "[No] object the size of Saturn or larger exists out to a distance of 10,000 astronomical units (AU), and no object larger than Jupiter exists out to 26,000 AU."
NASA's WISE Spacecraft Discovers Most Luminous Galaxy in Universe
NASA's NEOWISE Mission Finds 72 Additional Near-Earth Objects
Two New Kuiper Belt Objects Boost the Case for "Planet Nine"
The Mysterious 'Planet Nine' Might be Causing the Whole Solar System to Wobble