Astronomers discover largest solar system
Astronomers have discovered the largest known solar system, consisting of a large planet that takes nearly a million years to orbit its star.
The gas giant is one trillion kilometres away, making its orbit 140 times wider than Pluto’s path around our Sun.
Only a handful of extremely wide pairs of this kind have been found in recent years.
The planet, known as 2MASS J2126-8140, is between 12 and 15 times the mass of Jupiter.
“We were very surprised to find such a low-mass object so far from its parent star,” said Dr Simon Murphy .
“There is no way it formed in the same way as our solar system did, from a large disc of dust and gas.”
This system is nearly three times the size of the previous widest star-planet pair.
The star and its planet were found by a survey of young stars and brown dwarfs in Earth’s neighbourhood.
Once team members discovered they were a similar distance from the Earth – about 100 light-years – they compared the motion of the two through space and realised they were moving together.
“We can speculate they formed 10 million to 45 million years ago from a filament of gas that pushed them together in the same direction,” Dr Murphy explained.
“They must not have lived their lives in a very dense environment. They are so tenuously bound together that any nearby star would have disrupted their orbit completely.
Source: BBC
N.H.Khider