When you look up at the night sky, you'll notice that stars twinkle. That twinkle is in fact pulsations, as stars tend to pulsate. 
Interesting EngineeringBy Fabienne Lang
© Gabriel Pérez Díaz/IAC | Teardrop-Shaped Star Only Pulses on One Side, Making It the First of Its Kind

This is usually the same for all-stars, however, amateur astronomers have recently discovered a star that pulsates only on one side. 
Referred to by the rather un-twinkling name of HD74423, the one-sided pulsating star has taken on a teardrop shape because of a close companion pulling it out of its regular pattern. 
The findings were published in Nature Astronomy on Monday.

A one-sided twinkle

The star in question is around 1.7 times the mass of the Sun and is located about 1,500 light-years away from Earth. But the star isn't all on its own out there, it's accompanied by a red dwarf star. These two stars orbit each other in the short span of two Earth days.

It is precise because of this gravitational pull as they orbit each other that HD74423 is pulled into a teardrop shape and pulses just on one side. This is what is making the star pulsate in this extraordinary manner. 
"Stars that pulsate have been known in astronomy for a long time," said Zhao Guo, an author of the study. "The rhythmic pulsations of the stellar surface occur in young and in old stars, can have long or short periods, a wide range of strengths, and different causes. There is however one thing that, until now, all of these stars had in common: The oscillations were always visible on all sides of the star."
However, with HD74423 that's not quite the case as it only pulsates on one side. The amateur astronomers discovered this by closely analyzing data from the planet-hunting TESS satellite. 
This article was originally published by Interesting Engineering.
Previous Post Next Post