The asteroid Elektra was discovered in 1873, when it orbited the asteroid belt between Mars and Jupiter.
In 2003, astronomers discovered the existence of a moon orbiting around this object and in 2014 a second moon was discovered moving around it.
Now, scientists claim to have found a third moon, which could make Elektra a unique case: the first known quadruple asteroid in the solar system.
A group of astronomers from the National Institute for Astronomical Research in Thailand used images from Chile’s Very Large Telescope (VLT) to take a closer look at Elektra and found evidence of a moon that seemed hidden inside the orbits of the other two. .
“It is the first asteroid with three moons. We’re pretty sure. It is very exciting”, says Anthony Berdeu, in charge of the study.
NASA’s DART mission is scheduled to collide with the moon of one of these asteroids later this year.
The last moon discovered would have a diameter of a kilometer and a half, being a little smaller than the previous ones, of 1.2 and 3.7 kilometers in diameter.
The moon orbits Elektra once every 16 hours at a distance greater than 350,000 kilometers.
Berdeu explains that he was able to find this moon using a new algorithm to extract its weakest light in the images taken by the VLT. These data reduction techniques used by the algorithm allowed access to a larger image of Elektra and its surroundings.
The scientists’ finding has just been published in the journal Astronomy & Astrophysics.