Hubble celebrates 29th birthday with photo of hourglass-shaped Southern Crab Nebula

A few more nights of sleep and then the time has come: the Hubble telescope will turn 29 on April 24. It will then be exactly 29 years since the telescope was launched. In honor of this ‘birthday’, NASA and ESA have published a colored photo of the Southern Crab Nebula.

The nebula’s curious tentacle and hourglass shape is caused by the interaction of two stars in a binary system formed by an ancient red giant and a white dwarf. The red giant sheds its outer layers and this material is partly attracted by the gravity of the white dwarf. As a result, both stars are in a flat disk of gas that allows gas to escape only from the top and bottom of the disk, resulting in an hourglass shape, according to NASA. The ‘legs’ are probably formed by escaped gas colliding with surrounding interstellar gas and dust.

The recent image was based on images from March taken with an extensive set of color filters on the Wide Field Camera 3. The final published image is a combination of multiple images shot in a variety of colors of light. These colors correspond to the glowing gases in the nebula, where red is sulfur, green is hydrogen, orange is nitrogen and blue is oxygen.

Located about 7,000 light-years from Earth, the Southern Crab Nebula is officially called Hen 2-104 and is not to be confused with the Crab Nebula, a supernova remnant in the constellation Taurus. The nebula was also photographed by Hubble in 1999 and only then did it become clear that it was two stars.