A planet usually doesn't survive the death of a star. The Sun will swallow the Earth when it turns giant and red, some stars explode, among other deaths. But scientists have detected first surviving planet.
The international team of scientists used NASA's Transiting Exoplanet Survey Satellite (TESS) space observatory and the now retired Spitzer Space Telescope, also from NASA.
The study, published in the journal The Astrophysical Journal Letters , found a single planet orbiting the remains of what was once a fairly sun-like star.
Quite a death
Remember I told you about the Sun going giant and red? So that happened to this star, and today it's a white dwarf just a little bit bigger than the Earth - about 40% bigger.
When a Sun-like star runs out of fuel, therefore, it becomes the red giant. But at some point, it ejects its outer layers of gas, losing up to 80% of its mass.
The white dwarf, therefore, is the equivalent of just the core of the star. It will still remain somewhat active, but the predominance of its brightness comes from residual heat.
The planet, on the other hand, the size of Jupiter. Its size is equivalent to seven times that of the white dwarf, although its mass is still greater, because the matter of a star is more compressed.
Every 36 hours, the planet, called WD 1856 b, makes one turn around the star, called WD 1856 + 534. In other words, a year there lasts the equivalent of one and a half Earth days.
However, of course the passage of time there doesn't differ that much, A year is just an earthly timestamp, You wouldn't die any sooner if you were there, A year is just the speed that the planet revolves around the star.
Uncovering the first surviving planet
"WD 1856 b somehow got very close to its white dwarf and managed to stay in one piece," says Andrew Vanderburg, assistant professor of astronomy at the University of Wisconsin-Madison in a statement .
It's unlikely the planet was around when it expanded into a red giant. The star would swallow it up, destroy it, absorb it. There's no way it could survive.
"The white dwarf creation process destroys nearby planets, and anything that then gets too close is usually torn apart by the star's immense gravity," Vanderburg explains.
The question is not how exactly the planet survived, but how the star pulled it in. At the moment, scientists are trying to create some scenarios that explain the event.
"The most likely case involves several other Jupiter-sized bodies near the original orbit of WD 1856 b," says Juliette Becke, planetary scientist at Caltech, USA.
Now, scientists are trying to search for answers to explain what happened out there. In addition, the discovery has other implications for the study of exoplanets.
Finding the first surviving planet around a white dwarf, means that looking for rocky planets around them could be promising. Before, scientists ignored this possibility. Life could therefore be more common than we imagine.
"Under the right conditions, these worlds could maintain favorable conditions for life for longer than the time scale predicted for Earth," explains Lisa Kaltenegger, one of the study's co-authors.
The study was published in the journal The Astrophysical Journal Letters . With information from NASA .