David Pescovitz: Astronomers have captured the first image of a comet-like tail behind a star. The star, Mira, is named for the Latin word meaning “wonderful.” The tail is 20,000 times the distance between Pluto and our sun. Mira is hurtling through space at 291,000 miles per hour.
“I was shocked when I first saw this completely unexpected, humongous tail trailing behind a well-known star,” says Christopher Martin of the California Institute of Technology. “It was amazing how Mira’s tail echoed on vast, interstellar scales the familiar phenomena of a jet’s contrail or a speedboat’s turbulent wake.” Martin is the principal investigator for the Galaxy Evolution Explorer (telescope), and lead author of a Nature paper appearing today to announce the discovery.
Astronomers say Mira’s tail offers a unique opportunity to study how stars like our sun die and ultimately seed new solar systems. Mira is an older star called a red giant that is losing massive amounts of surface material. As Mira hurtles along, its tail sheds carbon, oxygen and other important elements needed for new stars, planets and possibly even life to form. This tail material, visible now for the first time, has been released over the past 30,000 years.
“This is an utterly new phenomenon to us, and we are still in the process of understanding the physics involved,” says co-author Mark Seibert of the Observatories of the Carnegie Institution of Washington in Pasadena. “We hope to be able to read Mira’s tail like a ticker tape to learn about the star’s life.”