Astronomy Picture of the Day

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.

2024 July 23
A multi-coloured nebula is shown that is the expanding
remnant of an exploded star. The central white and purple
colours show X-ray light, while the outer red and blue colours
show visible light. 
Please see the explanation for more detailed information.

The Crab Nebula from Visible to X-Ray
Image Credit: NASA, ESA, ASI, Hubble, Chandra, IXPE

Explanation: What powers the Crab Nebula? A city-sized magnetized neutron star spinning around 30 times a second. Known as the Crab Pulsar, it is the bright spot in the centre of the gaseous swirl at the nebula's core. About 10 light-years across, the spectacular picture of the Crab Nebula (M1) frames a swirling central disk and complex filaments of surrounding and expanding glowing gas. The picture combines visible light from the Hubble Space Telescope in red and blue with X-ray light from the Chandra X-ray Observatory shown in white, and diffuse X-ray emission detected by Imaging X-ray Polarimetry Explorer (IXPE) in diffuse purple. The central pulsar powers the Crab Nebula's emission and expansion by slightly slowing its spin rate, which drives out a wind of energetic electrons. The featured image released today, the 25th Anniversary of the launch of NASA's flagship-class X-ray Observatory: Chandra.

Many Discoveries: Chandra Celebrates 25th Anniversary
Tomorrow's picture: spikey moon


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