Halloween is just around the corner, and it seems the universe is also as excited as the denizens of the planet and has created stars which resemble Jack-O-Lantern. Making use of the data from the NASA Kepler and Swift missions, astronomers discovered this incredible group of pumpkin stars which spin so fast to flatten them much akin to actual pumpkins. Of course, we cannot sculpture faces or prepare a tasty pie of this pumpkin.
NASA has been monitoring a huge patch of sky, seeking out new worlds by looking for brightness changes which are caused when exoplanets passed in front of host stars. Kepler’s field of view was minutely studied, and astronomers used the Swift mission to search for X-rays sources which Kepler must have seen. What they saw belied their assumptions. The pumpkin stars radiate X-rays which are 100 times more intense than the peak levels seen from the sun.
These stars which are 18 in number rotate in just a few days while the sun takes almost a month to rotate once on its axis. The rapid spinning also means other types of activities such as flares and spots will be amplified many times.
The best example of this freak phenomenon is the KSw 71 which is an extreme spinning pumpkin star and is ten times the size of our sun. It spins four times faster than our parent star and produces 4000 times more powerful X-Rays than our sun.
A Pumpkin star is formed when a close binary system composed of two Sun-like stars rotate faster as they gate closer and merge to form a pumpkin star. This transition takes about 100 million years which is a small period in the star’s life. The swift study also revealed 93 X-ray objects —50 % of them are active galaxies while the remaining are different X-Ray emitting stars.