Scientists Thursday reported new evidence that a gassy "wind" is spurting out two opposite sides of a nearby galaxy at speeds up to 240 miles a second.
The wind is apparently driven by repeated supernova star explosions, said astronomer R. Brent Tully.
The evidence, an analysis of light from the galaxy, is published in the British journal Nature by Tully and Jonathan Bland of the Institute for Astronomy in Honolulu, Hawaii.
A galaxy is a cluster of stars, gas and dust. The study focused on one called M82, visible with a small telescope, which lies some 60 trillion miles away in the direction of the constellation Ursa Major.
Tully said other scientists had suggested the idea of a wind from M82 because of previous observations. No other galaxy has a well-documented wind, he said in a recent telephone interview.
The wind, mostly hydrogen, appears to be going faster and faster the farther it gets from the galaxy, he said. It apparently began at least 3 million years ago and maybe tens of millions of years ago, he said.