December 3, 2008 - Mauna Kea, Hawaii

In 1572, Danish astronomer Tycho Brahe observed what he thought was a new bright star in the night sky, but it disappeared a little over a year later.

Today, astronomers working at the Subaru Telescope announced they were able to observe a "light echo" from this star, and have confirmed that it was actually a rare supernova event, when the death of a star sends out a violent burst of energy.

According to a news release from the Subaru telescope, "A ‘light echo’ is light from the original supernova event that bounces off dust particles in surrounding interstellar clouds and reaches Earth many years after the direct light passes by; in this case, 436 years ago. This same team used similar methods to uncover the origin of supernova remnant Cassiopeia A in 2007."

In the same release, lead project astronomer Dr. Tomonori Usuda said, "using light echoes in supernova remnants is time-travelling in a way, in that it allows us to go back hundreds of years to observe the first light from a supernova event. We got to relive a significant historical moment and see it as famed astronomer Tycho Brahe did hundreds of years ago. More importantly, we get to see how a supernova in our own galaxy behaves from its origin."

The results of this study appear in the December 4, 2008 issue of the science journal Nature.

The image of the supernova above is courtesy the Subaru telescope, and is a "Wide Field Image of Tycho's Supernova Remnant." According to the news release, the image is "a color composite of Mid-Infrared by Spitzer Space Telescope (red), and X-ray (blue: high-energy X-ray, green: middle energy, yellow: low-energy) by Chandra X-Ray Observatory on Near-Infrared by Calar Alto 3.5m Telescope. The remnant is approximately 25 ly in diameter."

Also in the above video is a diagram of the "light echoes", explained in the news release as follows: "The optical light arrived at Earth in 1572 (sky blue arrow). Optical light was scattered by dust cloud around the supernova arrived in 2008 (yellow arrows). Since the emitting regions were apparently shifted from 23 August 2008 to September 24, the optical lights were confirmed as light echoes."