The National Aeronautics and Space Administration’s (NASA) Spitzer and Swift space telescopes joined forces to illuminate a microlensing event and spotted a brown dwarf.
Microlensing is when a cosmic star brightens due to the gravitational field of another star in the foreground. In other words when two cosmic objects align and the light from the background star is deflected by the foreground star, the background star lights up thus showing the observing telescopes this object clearly.
The newly discovered brown dwarf is named OGLE-2015-BLG-1319. It is for the first time that two space telescopes have collaborated to observe a microlensing event, according to a press release by NASA.
“We want to understand how brown dwarfs form around stars, and why there is a gap in where they are found relative to their host stars,” said Yossi Shvartzvald, lead author of the study published in the Astrophysical Journal. He is a postdoctoral fellow based at NASA’s Jet Propulsion Laboratory, Pasadena, California.
“Anytime you have multiple observing locations, such as Earth and one, or in this case, two space telescopes, it’s like having multiple eyes to see how far away something is,” Shvartzvald said. “From models for how microlensing works, we can then use this to calculate the relationship between the mass of the object and its distance.”
Spitzer is over 1 AU (1 AU is the distance between Earth and the sun)away from Earth in the orbit around the sun, while Swift circulates in orbit around the Earth.
Brown dwarfs are the bridge between planets and orbiting stars, according to scientists and have a mass 80 times that of Jupiter although their core is not hot or dense like stars.
The news dwarf, say researchers, has a mass density of 30 to 65 Jupiters. It is orbiting the K dwarf and the distance between the two is possibly 0.25 AU and 45 AU based on available data.
“In the future, we hope to have more observations of microlensing events from multiple viewing perspectives, allowing us to probe further the characteristics of brown dwarfs and planetary systems,” said Geoffrey Bryden, JPL scientist and co-author of the study.