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A giant Jupiter-like planet that survived the cataclysmic death of its star has provided astronomers with a preview of the far future of our solar system.

The planet, known as MOA-2010-BLG-477Lb, was first spotted in 2010, but now at the University of Tasmania in Australia and his colleagues have confirmed that it orbits a white dwarf, the stellar remnant left when stars like our sun run out of fuel to burn.

Jupiter-like planets have been spotted around white dwarfs before, hinting that they can survive this dramatic transformation, but these were much closer to their stars, suggesting a momentous change in position. This is the first time such a planet has been seen in its original orbit.

Astronomers first discovered the planet and its host star using a microlensing event. These occur when an object, such as a planet or star, moves in front of another star and its gravitational field magnifies the light of the background star, causing it to appear brighter.

Studying this change in light can reveal the characteristics of the foreground object. at the University of Toulouse in France and his colleagues analysed a 2010 microlensing event to identify a foreground star similar to our sun, called MOA-2010-BLG-477L, with an accompanying planet, MOA-2010-BLG-477Lb.

Blackman and his team undertook follow-up observations of this region between 2015 and 2018 at the Keck Observatory in Hawaii. 鈥淲hat we expected to see was two stars, the star in the foreground [MOA-2010-BLG-477L] and background separately,鈥� says Blackman, because the two stars would have continued on their individual trajectories. 鈥淏ut in this case, we didn鈥檛, because that star was too faint.鈥�

The researchers realised that MOA-2010-BLG-477L must be a white dwarf, not a sun-like star as previously thought. With data from the 2010 microlensing event and a sample of 130 known white dwarfs, the team estimated the star鈥檚 mass to be around 0.53 that of the sun and the mass of its companion planet at roughly 1.4 times that of Jupiter. The planet orbits at 2.8 the distance of Earth from the sun. Jupiter orbits the sun at 5.2 times Earth鈥檚 distance.

鈥淭his study is a snapshot into the future of the solar system,鈥� says Blackman, providing a greater insight into how Jupiter and other outer planets will fare after the death of our own sun.

at Imperial College London says: 鈥淭his is a big detection in the field of white dwarf planetary systems, as it is the first direct detection of a planetary body orbiting at a distance similar to Mars and Jupiter in our own solar system.鈥�