Breaking Discovery: A Massive Seyfert Energy Flare Shredded Our Galaxy Just 3.5 Million Years Ago
A research team of astronomers reports evidence of a Seyfert energy flare decimating the Milky Way galaxy some 3.5 million years ago, according to the BBC. Their findings will be published in the latest edition of the peer-reviewed Astrophysical Journal.
That's not very long ago, in the grand scheme of things. EarthSky contextualized it nicely by noting that, when this flare occurred, dinosaurs had already been extinct for well over 63 million years. The flare erupted when mastodons wandered the Earth during the Pliocene Epoch.
According to astronomers, the flare's massive size means it could have only come from Sagittarius A* – the supermassive black hole in the center of the Milky Way galaxy. The blast ripped through our galaxy for 300,000 years, sending shockwaves hurtling up to 200,000 light-years away and displacing part of the Magellanic Stream – which is a long cloud of gas emanating from two nearby dwarf galaxies that stretches nearly halfway around the Milky Way.
Watch the animation here:
(Credit: James Josephides/ASTRO 3D)
A Seyfert flare is a colossal burst of radiation originating near a black hole that then spirals out into a cone shape – this one created two. The team believes that this devastating explosion is what formed the Fermi Bubbles that were discovered in 2010: two enormous spherical structures at the center of the Milky Way extending for 25,000 light-years each. Lead astronomer Joss Bland-Hawthorn describes the burst this way: "The flare must have been a bit like a lighthouse beam. Imagine darkness, and then someone switches on a lighthouse beacon for a brief period of time."
Sagittarius A* is a supermassive black hole in the heart of our galaxy, the hub around which the Milky Way turns. It has a mass of 4 million Suns and rests a mere 26,000 light-years from Earth. Scientists had always believed the Milky Way to be a fairly quiet galaxy compared to others but – since we don't know how to gauge where or when another flare will hit – now it seems we'll be keeping a closer eye on our own back yard.