A Zombie Star


zombieA team of astronomers using the Hubble Space Telescope has found a star system that may have left behind a “zombie star” after an unusually weak supernova explosion. A supernova normally obliterates the exploding white dwarf, and the star effectively dies. Scientists believe this faint supernova may have left behind a surviving portion of the dwarf star—a sort of zombie star. The two inset images show before-and-after images captured by Hubble of Supernova 2012Z in the spiral galaxy NGC 1309. The white X at the top of the main image marks the location of the supernova in the galaxy.

Image Credit: NASA

A “Young” Supernova Remnant


g306_wideAstronomers estimate that a supernova explosion occurs perhaps a couple of times a century in the Milky Way. The expanding blast wave and hot stellar debris slowly dissipate over hundreds of thousands of years, eventually mixing with and becoming indistinguishable from interstellar gas. The Swift satellite uncovered the previously unknown remains of a shattered star during an X-ray survey of the galaxy’s central regions. The new object, named G306.3-0.9 after it’s coordinates in the sky,is among the youngest of the 300+ known supernova remnants in the Milky Way. Analysis indicates that G306.3–0.9 is probably less than 2,500 years old. That would make it one of the 20 youngest supernova remnants identified.

This composite image of G306.3–0.9 (the blob in the lower left) was stitched together using data from Chandra X-ray observations (blue), infrared data acquired by the Spitzer Space Telescope (red and cyan) and radio observations (purple) from the Australia Telescope Compact Array.

G306_Swift_XRTjpgThe image on the left was taken in February, 2011, using Swift’s X-ray Telescope as part of the Galactic Plane Survey. The dots in the image indicate where X-rays struck the detector. Despite this short 8.5-minute exposure, the extended circular patch of G306.3–0.9 stands out quite nicely.

Image Credits: NASA

A Cosmic Puff Ball


sn1006This cosmic puff ball is the remains of the brightest supernova in recorded history. In AD 1006, a supernova lit up the nighttime skies  and was seen by observers China, Egypt, Iraq, Italy, Japan, and Switzerland. This image was assembled from data at three different wavelength  of X-rays taken from orbit by Chandra X-ray Observatory. The debris cloud from what is now called the SN 1006 supernova remnant is about 60 light-years across. It’s the remains of a white dwarf star that was part of a binary star system. The white dwarf gradually captured ate its companion star, and the increase in mass caused a thermonuclear explosion. Because the supernova remnant is about 7,000 light-years away, that explosion actually happened 7,000 years before the light reached Earth in 1006, or in roughly 6000 BC.

Image Credit: NASA

A Supernova Remnant


The thin, red veins of energized gas in this image from the Spitzer Space Telescope are the remains of supernova HBH3. The puffy, white feature in the image is a region of star formation. In this false color image, Infrared wavelengths of 3.6 µm have been mapped to blue, and 4.5 µm to red. The white color of the star-forming region is a combination of both wavelengths. The HBH3 filaments show up only at the longer 4.5 µm wavelength.

Image Credit: NASA