NASA shares 'Astronomy Picture of the Day'; features unusual CBT-1 nebula

NASA on Sunday shared the much anticipated 'Astronomy Picture of the Day' that featured an unusual Supernova remnant (SNR) dubbed as the 'CTB-1' which is approximately 7500-11,000 years old and lies in the constellation Cassiopeia. This supernova remnant [Abell 85], according to NASA, is an expanding gas shell that is a major source of optical, radio, and X-ray emissions. CBT-1 was formed after a massive star toward the constellation of Cassiopeia exploded about 10,000 years ago. Why this nebula glows in X-ray light remains a mystery, NASA says. 

"The star likely detonated when it ran out of elements near its core that could create stabilizing pressure with nuclear fusion," NASA explained in a release. 

Credit: NASA

CTB-1 is 'extremely dim'

Medulla Nebula, a resulting supernova remnant from the collision that is known for its unique brain-like shape, glows in visible light from the heat generated by its collision with confining interstellar gas. NASA lists a hypothesis that an extremely energetic pulsar was co-created during the explosion that powers the nebula with a fast outwardly moving wind. Subsequently, a pulsar was also detected in radio waves, which is believed to have been expelled by the supernova explosion at over 1000 kilometres per second.

"Although the Medulla Nebula appears as large as a full moon, it is so faint that it took many hours of exposure with a telescope in Seven Persons, Alberta, Canada to create the featured image," NASA stated in a release. 

CTB-1 is extremely dim, according to scientists. More than 28 hours of exposure time in Hα and 23 hours of exposure time in OIII narrow band filters were necessary to capture the image of the CTB-1, according to Moravian Instruments Cameras for Astronomy. Every single exposure with the G3-16200 camera on a 30 cm corrected Newtonian telescope was 20 minutes long to be able to see the supernova remnant. A gaseous bubble-like image is detected and when another 10 hours of exposure are set through regular red, green, and blue filters, scientists get mcu clear image. Another study also claimed that a pulsar was born from the supernova that produced CTB 1 and ejected into the galaxy, travelling at a velocity exceeding 1000 km/s.