On this doomed planet, the year lasts only sixteen hours

On this doomed planet, the year lasts only sixteen hours

A group of astronomers have announced the discovery of the planet with the shortest known orbit, and this gas giant makes one turn around its star in just 16 hours, and it's getting faster, so that it can soon be absorbed.

Hot Jupiters.

To date, astronomers have identified about 100 of these planets in the Milky Way, of which few have orbital periods of less than 24 hours.

A team of astronomers led by Avi Sporer from the Massachusetts Institute of Technology announced that they had discovered a world that was spinning around its star in just 16 hours, and that you would find it in the 855 light years from Earth in the constellation Hercules.

Researchers have identified this planet as TOI-2109b in NASA's Transiting Exoplanet Survey Satellite, which has been in Earth orbit since April 2018.

This observatory is calibrated to detect the presence of extraterrestrial worlds spinning around their stars in very close orbits. Note that TESS does not see these planets directly, but rather monitors the small failures of brightness that give out their repeated passageways in front of its star.

In the case of TOI-2109b, these failures occurred every 16 hours. According to the release, this is faster than any other gas giant found to date.

Since then, subsequent analyses have revealed several features. First, this planet orbits only 2.4 million kilometres from its star. In comparison, Mercury is about 24 times further from the Sun. According to an analysis, TOI-2109b is also five times larger and about 30 percent larger than Jupiter. Its star is about twice as large and as large as the Sun. Finally, TOI-2109b is also the second hottest known exoplanet: it has a daily temperature of almost 3,300 degrees Celsius.

Perhaps the most intrigued feature of TOI-2109b for astronomers is changing its orbit. It seems that the planet moves closer to its star and its orbit accelerates at a rate of between 10 and 750 milliseconds a year. This is unprecedented. We will not see it disappear in our lifetime, but astronomers estimate that it can be absorbed by its star for 10 million years.