Pumpkin Stars Discovered In Time For Halloween

Astronomers discovered a new class of rapidly rotating stars with a red-orange color. They also have a squished shape that earned them the name "pumpkin stars," just in time for the holiday.

However, despite having such a name, IFL Science noted that these stars are actually the result of stellar mergers - something that was proposed 40 years ago by Ronald Webbink, who said that close binary systems cannot survive once the supply of one star dwindles and starts to enlarge. The stars then coalesce to form a single, rapidly spinning star in a so-called "excretion disk" formed by gas, thrown out during the merger. The disk then dissipates over the next hundred million years, leaving behind the very active, spinning pumpkin stars.

The current study's co-author, Elena Mason, a researcher at the Italian National Institute of Astrophysics Astronomical Observatory of Trieste told Science Daily that the study now combined the power of the Kepler telescope and the Swift observatory to find stars emitting a lot of X-rays - which is the sign for the existence of these objects.

The paper, which was published in the Astrophysical Journal, discussed the properties of these 18 newly discovered stars - which are said to emit at least 100 times more X-rays than the Sun. The most extreme case seen is the KSw 71 - a star that is 10 times larger than our sun, and produces 4,000 times more X-rays, spinning on its axis in just 5.5 days.

Mason shared, "Webbink's model suggests we should find about 160 of these stars in the entire Kepler field. What we have found is in line with theoretical expectations when we account for the small portion of the field we observed with Swift."

Of course, the study did not stop with the pumpkin stars - the team is already extending their Swift observations to additional fields mapped by their K2 mission.