A mysterious cosmic object capable of moving extremely fast through the Milky Way, at an impressive rate of more than a million kilometres per hour, has been intercepted by citizen scientists from NASA's ‘Backyard Worlds: Planet 9’ project, whose aim is to search for planets and brown dwarfs beyond the orbit of Neptune.
La discovery, although signed by amateur enthusiasts, is published in the prestigious journal Astrophysical Journal Letters.
The mysterious object has a mass similar to that of a small star, and was spotted in “auto-velox” style by Nasa's Wise telescope, which mapped the infrared sky from 2009 to 2011
But what is this galactic Speedy Gonzales? At the moment, one hypothesis is that it is a brown dwarf, i.e. an object whose mass is between that of a giant planet and a star like the Sun, although this speed is unheard of even for such bodies.
It is therefore unclear what it is or why it is so fast. Perhaps “Speedy” was part of a binary system in which one of the two stars exploded as a supernova, or it was part of a globular cluster and would have flown away on impact with a black hole.
Italian Italian 
English
French
Spanish
German
