Astronomers have used a fleet of tiny satellites to take a precise measurement of the interaction between two stars in the constellation of Orion. In doing so, they discovered the biggest stellar heartbeat known to date.
The research, published in the Monthly Notices of the Royal Astronomical Society, describe the binary system Iota Orionis in great detail. The stars in the system orbit each other in a highly elliptical 29-day orbit. For about 90 percent of the time, they go about unchanged, but for the remaining time, they get so close that their gravity forces them to change shape, massively increasing their luminosity.
“The variations look strikingly similar to an electrocardiogram showing the sinus rhythms of the heart, and are known as heartbeat systems,” Herbert Pablo, the project's principal investigator, a post-doctoral researcher at University of Montréal and member of the Centre for Research in Astrophysics of Quebec, said in a statement.
The system is massive, with the two stars weighing collectively 35-times the mass of the Sun. Their mass and unusual interaction allow astronomers to use asteroseismology techniques on the star. Practically, they can work out the interior of the stars by looking at how it vibrates.
“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,” Pablo added.
The data was collected from the BRIght Target Explorer constellation (BRITE), a group of five nanosats that are being used to investigate the brightest stars in the sky. “As the first functional nanosatellite astronomy mission, the BRITE-Constellation is at the vanguard of this coming space revolution,” said Canadian BRITE-Constellation principal investigator Gregg Wade of the Royal Military College of Canada.
The team hope that these observations will launch more campaigns to understand the complex lives of massive stars. They might not be as numerous as yellow or red stars, but they are the cradles of all the heavy elements that make humans and life possible.