Iota Orionis – a massive pulsating star in the Orion constellation

Astronomers from the BRITE  Constellation project and Ritter Observatory have discovered a massive star with repeating one percent spike in its light, and this may change our understanding about this type of stars.

The star is Iota Orionis, a part of a binary system. It is the brightest star in the Orion constellation and visible with the naked eye.

The inimitable change in brightness of this star was detected by the world’s smallest space satellites, known as nanosats.  “As the first functional nanosatellite astronomy mission, the BRITE-Constellation is at the vanguard of this coming space revolution,” said the BRITE-Constellation principal investigator Gregg Wade, who comes from the Royal Military College in Canada.

The light that comes from Iota Orionis is stable for 90% of the time, and then a dip is followed by a large spike. “The variations look strikingly similar to an electrocardiogram showing the sinus rhythms of the heart, and are known as heartbeat systems,” said Herbert Pablo, researcher and the project’s principal investigator.

This peculiar variation is caused by the highly elliptical 30-day orbit of the two stars.

The two stars spend the majority of their time far away, but in one point they come 8 times closer than normally. At this specific point, the gravity becomes so strong that it distorts their shapes and causing the variations in brightness.

Iota Orionis is the first massive system that experiences such distortions. It is 35 times the mass of our Sun.

Such pulsating stars help us understand the universe

The interesting thing is that this allows us to peer into these stars. “The intense gravitational force between the stars as they move closer together triggers quakes in the star, allowing us to probe the star’s inner workings, just as we do for the Earth’s interior during Earthquakes,” said Pablo.

Those kind of quakes are very rare in such a massive star like Iota Orionis. They can also lead us to finding out how these stars evolved.

Astronomers hope that this finding changes how we study the evolution of massive stars . This is very important, because massive stars create the elements needed for life in the universe.