Black Hole Of The Milky Way Shreds Stars In A Day

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A new study by Eden Girma, an undergraduate student at Harvard University and a member of the Banneker/Aztlan Institute, has found that every few thousand years a star wanders too close to the black hole present at the core of our galaxy - the Milky Way. The black hole shreds the stars in a day through a process called tidal disruption. In about a year, the resulting fragments pull together to form planet-sized objects which are then hurled outward.

The black hole is 'spitting' these planet-sized objects at the speed of 20 million miles per hour (or 10,000 km per second). According to the Phys magazine, every few thousand of years a star strays near the galactic center where the black hole of the Milky Way shreds it apart with its powerful gravitational force in just a day. A long streamer of gas and star material then whips outward.

The new research shows that in about a year, this gas pulls together into planet-sized objects that are flung throughout the galaxy and beyond it like a cosmic 'spitball'. A single star that blows up provides enough material to form hundreds of such planet-sized cosmic balls.

The Astronomy magazine speculates that some of these balls may be as big as the size of the Jupiter, and may weigh somewhere between Neptune to several Jupiters. They may glow when they get formed but not bright enough to be detected by the instruments we have now. Future instruments (like Large Synoptic Survey Telescope and James Webb Space Telescope) which are under development now might be able to detect them.

Girma, who is going to present her findings at a meeting of the American Astronomical Society on January 13, 2017, calculated that the closest of these planet-mass objects may land within a few hundred light-years of the Earth. She also found that 95 per cent of these planet-mass objects will be thrown out of the galaxy because of the speed at which they are shot.

James Guillochon of the Harvard-Smithsonian Center for Astrophysics (CfA), who is the co-author of the study, explained that other galaxies like Andromeda also keep shooting such cosmic balls at us all the time. They are much different than 'typical' planets as they are made up of material from different stars and thus, have different compositions. They are also formed much more quickly than a normal planet (through a process called tidal disruption) which takes millions of years to form.