
Scientists were amazed to spot the remains of a planet circling a dead star.
For the first time, NASA’s scientists were able to witness a solar system being destroyed, giving a window into what our demise will look like once the sun goes kaput.
NASA’s Kepler 2 Mission has found the remains of a planet circling a white dwarf, which is a dead star, about 570 light years away from us, according to a Guardian report.
The planet has been torn apart as it circles the white dwarf in the Virgo constellation, with chunks of the planet whipping around the dead star at a rate of once every five hours at a very close proximity to the star — just 520,000 miles, which is just twice the distance between the Earth and the moon.
No human has ever witnessed this, Andrew Vanderburg of the Harvard-Smithsonian Center for Astrophysics was quoted as saying in the report. He said the scientists are actually witnessing a solar system like ours get destroyed.
A star dies when the hydrogen that it depends on for nuclear reactions runs out, causing it to burn heavier elements like carbon and oxygen, leading to a dramatic expansion and causing the star to lose its outer lays with nothing but an Earth-sized core behind. This is called a white dwarf.
The Kepler 2 mission was created to find new planets, and it has more than done its job since getting launched back in 2009. Besides spotting numerous Earth-like planets well beyond our solar system, it has led to other discoveries like this one that has expanded scientists’ knowledge of our universe. Kepler 2 is capable of spotting the dimming of stars caused by planets circling them and can provide estimates of how large and how distant the planet is, as well as the speed of its orbit.
Scientists used Kepler 2 to watch a white dwarf called WD1145+017, and noticed that there was a 40 percent drop in light from the star every 4.5 hours. Other telescopes confirmed these observations, and more research seemed to indicate that there were a few lumps of rock that were orbiting the star.
The findings were published in the journal Nature, which can be found here. The abstract is excerpted below:
“Most stars become white dwarfs after they have exhausted their nuclear fuel (the Sun will be one such). Between one-quarter and one-half of white dwarfs have elements heavier than helium in their atmospheres1, 2, even though these elements ought to sink rapidly into the stellar interiors (unless they are occasionally replenished)3, 4, 5. The abundance ratios of heavy elements in the atmospheres of white dwarfs are similar to the ratios in rocky bodies in the Solar System6, 7. This fact, together with the existence of warm, dusty debris disks8, 9, 10, 11, 12, 13 surrounding about four per cent of white dwarfs14, 15, 16, suggests that rocky debris from the planetary systems of white-dwarf progenitors occasionally pollutes the atmospheres of the stars17. The total accreted mass of this debris is sometimes comparable to the mass of large asteroids in the Solar System1. However, rocky, disintegrating bodies around a white dwarf have not yet been observed. Here we report observations of a white dwarf—WD 1145+017—being transited by at least one, and probably several, disintegrating planetesimals, with periods ranging from 4.5 hours to 4.9 hours. The strongest transit signals occur every 4.5 hours and exhibit varying depths (blocking up to 40 per cent of the star’s brightness) and asymmetric profiles, indicative of a small object with a cometary tail of dusty effluent material. The star has a dusty debris disk, and the star’s spectrum shows prominent lines from heavy elements such as magnesium, aluminium, silicon, calcium, iron, and nickel. This system provides further evidence that the pollution of white dwarfs by heavy elements might originate from disrupted rocky bodies such as asteroids and minor planets.”
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