Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
September 29, 1999
Explanation: Why does the Crab Nebula still glow? In the year 1054 A.D. a supernova was observed that left a nebula that even today glows brightly in every colour possible, across the entire electromagnetic spectrum. At the nebula's centre is an ultra-dense neutron star that rotates 30 times a second. The power liberated as this neutron star slows its rotation matches the power radiated by the Crab Nebula. The above picture by the recently launched Chandra X-Ray Observatory shows new details of the nebula's centre in X-ray light, yielding important clues to how the neutron star powers the nebula. Visible are rings of high-energy particles that are being flung outward near light-speed from the centre, and powerful jets emerging from the poles. Astrophysicists continue to study and learn from this unusual engine which continually transfers 30 million times more power than lightning at nearly perfect efficiency.
Authors & editors:
Jerry Bonnell (USRA)
NASA Technical Rep.: Jay Norris. Specific rights apply.
A service of: LHEA at NASA/ GSFC
& Michigan Tech. U.