The Picture Show
Wed September 28, 2011
Massive Star Served Sunny Side Up
The fried egg — a massive star surrounded by a double, outer ring of gaseous dust — is the closest yellow hypergiant star found neighboring Earth to date. Yellow hypergiants are rare, massive stars living in a phase of a star's life cycle that generally only lasts a few hundred thousand years — a flash in the lifespan of the galaxy. They consume a lot of energy to burn so brightly.
The entire body of the nebula — a yellow hypergiant "yolk" surrounded by "egg white" clouds of dust — sits about 13,000 light-years away from Earth.
"People had noticed this object glowing brightly before, but no one had identified it as a yellow hypergiant," says astronomer Eric Lagadec, part of the European Southern Observatory team that discovered the monster star while investigating neighboring stars.
The nebula is massive: It has a radius about 10,000 times the distance of the Earth to the Sun. For scale, if you were to put the center of the nebula at the center of our solar system — the Sun — then the outermost portion of the nebula's star would reach Jupiter. The outermost portion of the nebula's gaseous rings would stretch to some of the orbiting comets beyond Neptune.
Lagadec and his colleagues photographed the nebula with a heavy-duty telescope that uses infrared to capture images. The photo above shows the bright, shining star nestled in the middle of two outer shells of cosmic dust — gasses found all over the galaxy.
Those outer rings of dust are the remnants of previous explosions the star has undergone as it dies. Eventually, the star will explode in a supernova event, launching all of its gaseous matter into the universe. And when that happens, it will likely shine as bright as Venus and be visible during the day, Lagadec says.
"It could happen tomorrow or in a few hundred thousand years," he says.
This research has been accepted for publication by the journal Astronomy & Astrophysics.