Astronomers have discovered a new PINK planet on the edge of our Solar System.
The dwarf planet - given the name 2012 VP 113 by scientists - is 80 times further from the Sun than Earth.
It is 280 miles in diameter and is in a distant area of the Solar System way beyond Pluto once thought to contain no planets at all.
The pink-tinged lump of ice and rock circles the sun at a greater distance than any known object, never getting closer than 12bn km.
The object - dubbed 'VP' or 'Biden' after the US Vice President - is only the second to be found in a mysterious region at the boundary between the Solar System and outer space called the inner Oort Cloud.
Astronomers now believe there may be thousands of previously unknown objects orbiting the Sun at this distance.
And they believe that the pattern of the new planet's orbit suggests it is caused by the gravitational pull of a 'Super Earth' that traces such a large orbit around the Sun that it has never been seen.
Astronomer Scott Sheppard, who found the new planet with colleague Chad Trujillo, said: "If you took a Super Earth and put it a few hundred astronomical units out, the gravity could shepherd this new object into the orbit it has."
An astronomical unit is around 150 million kilometres.
The traditional view of the Solar System had been that of nine planets orbiting the Sun.
This was overturned in the 1990s when scientists found that Pluto is orbiting in a band of thousands of icy objects called the Kuiper Belt.
Beyond this belt only one object - another dwarf planet called Sedna - was thought to exist on its own.
(藝術家所描繪的Sedna)
But the latest discovery suggests that our Solar System has a number of planets at its edges.
Professor Andrew Coates, Head of Planetary Science at University College London's Mullard Space Science Laboratory, said: "This looks like a very exciting result giving a glimpse of what the inner Oort Cloud might tell us.
"This represents the real edge of the solar system, with objects in orbit around the Sun up to a quarter of the way to the nearest star.
"But the inner Oort Cloud is more difficult to detect, and the new result gives us a taste - including the possibility of planet-sized, previously undetected objects. We will have to wait for more results to find out for sure."
Chris Lintott, an astronomer at the University of Oxford, said: "There's something joyous in the fact there are still things to be discovered."
據英國《鏡報》3月27日報導，美國卡內基科學研究所天文學家斯考特·謝潑德在太陽系邊緣發現一顆粉紅色星球，並以美國副總統(VP，Vice President)的名字命名它。
這是一顆矮星，被命名為2012 VP113。它的直徑為450公裡，位於冥王星更外側的太陽系邊緣地區，科學家曾認為那裡沒有行星。這個由粉紅色冰和巖石組成的行星在圍繞太陽運轉。
這顆行星是在太陽系與被稱為「內奧爾特星雲」的外太空之間的神秘地區發現的第二個天體。天文學家們認為，或許在距離太陽極遠地帶，還有數千顆前所未知的物體圍繞太陽運行。科學家們認為，新行星圍繞太陽運行的方式預示出「超級地球」存在的可能，它可能圍繞太陽遠距離運行。
發現這顆粉色星球的天文學家謝潑德說：「如果將一顆超級地球放在數百個天文單位以外，重力會引導這顆新星球進入之前的軌道。」一個天文單位大約有1.5億公裡遠。
傳統觀點認為，太陽系有9大行星圍繞太陽運轉。但是這種觀點在20世紀90年代被推翻，當時科學家們發現冥王星正圍繞柯伊伯帶(Kuiper Belt)運轉，這裡有數以千計的冰冷天體。而在柯伊伯帶以外只有一個天體存在，即矮星Sedna。最新發現顯示，太陽系在邊遠地區也有許多行星。
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