M51 tagged posts

Whirlpool Galaxy (stock image). Credit: © allexxandarx / Fotolia

Astronomers have been keenly peering into M51, or the Whirlpool Galaxy, since the 1800s, its signature spiral structure informing the earliest debates over the nature of galaxies and the Cosmos at large. But no one – not with the naked eye or with increasingly powerful modern telescopes – has ever seen what Case Western Reserve University astronomers first observed using a refurbished 75-year-old telescope in the mountains of southwest Arizona. “I literally looked at the image and said, ‘What in the world is that?'” said Case Western Reserve astronomy professor Chris Mihos.

What it was turned out to be a massive cloud of ionized hydrogen gas spewed from a nearby galaxy and then essentially “cooked” by radiation from the gala...