Context

• An extremely distant dwarf planet, named The Goblin, has been discovered in observations that are redefining the outer reaches of the solar system.
• A new minor planet called “the Goblin” is the second most distant known object in the solar system.
  
  

About

• Formal Name:As assigned by the International Astronomical Union’s Minor Planet Center, the new dwarf planetwould be formally known as 2015 TG387.
• It is memorably nicknamed Goblin because its human examination occurred in roughly the Halloween time frame.Astronomers made the discovery while hunting for a hypothetical massive planet, known as Planet Nine.
• The Goblin dwarf planet appears to be under the gravitational influence of a giant unseen object, possibly a hypothetical massive planet referred to as Planet Nine.
• Telescope used:The Japanese Subaru 8-metre telescope located on the dormant Mauna Kea volcano in Hawaii was used.
• Why this telescope? The telescope is the only one in the world to be able to produce deep images capable of probing the outer reaches of the solar system, while it also has a wide enough field of view to be able to cover enough sky to discover rare objects.

About Goblin:

• Radius: The newly discovered icy world, estimated to be just 300km across, is in an extremely elongated orbit. At its closest, it gets about two and a half times as far from the sun as Pluto.
• Revolution time period: Then it heads off to the outermost fringes of the solar system, to almost 60 times further out than Pluto, taking an astounding 40,000 years to loop once around the sun.
• For 99% of its orbit, it would be too faint to see.

Significance

Why it is important:

• This will be adding to astronomers’ certainty that Planet Nine is out there.
• The object is the third minor planet to have been found in the outer solar system, following the discoveries of Sedna and, recently, another object called 2012 VP113. 
• Intriguingly the orbits of the three objects discovered so far appear to be clustered together, suggesting that they are being shepherded by a giant, unknown object. This has pointed astronomers to the existence of a ninth, super-Earth sized planet again.
• Planet Nine is suspected to be in orbit far beyond Pluto in a mysterious region known as the Oort Cloud.
  
  

Learning Aid