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.

2022 November 21
The featured image shows the Butterfly Nebula as imaged
by Hubble. The nebula appears very colorful due to a expansive
color map used by the digitizing processor. Please see the explanation for more detailed information.

The Butterfly Nebula from Hubble
Image Credit: NASA, ESA, Hubble; Processing: William Ostling

Explanation: Stars can make beautiful patterns as they age -- sometimes similar to flowers or insects. NGC 6302, the Butterfly Nebula, is a notable example. Though its gaseous wingspan covers over 3 light-years and its estimated surface temperature exceeds 200,000 degrees C, the aging central star of NGC 6302, the featured planetary nebula, has become exceptionally hot, shining brightly in visible and ultraviolet light but hidden from direct view by a dense torus of dust. This sharp close-up was recorded by the Hubble Space Telescope and is processed here to show off remarkable details of the complex planetary nebula, highlighting in particular light emitted by oxygen (shown as blue), hydrogen (green), and nitrogen (red). NGC 6302 lies about 3,500 light-years away in the arachnologically correct constellation of the Scorpion (Scorpius). Planetary nebulas evolve from outer atmospheres of stars like our Sun, but usually fade in about 20,000 years.

Tomorrow's picture: double space < | Archive | Submissions | Index | Search | Calendar | RSS | Education | About APOD | Discuss | >

Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
NASA Official: Phillip Newman Specific rights apply.
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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.

2022 November 22
The featured image shows two clusters of blue stars
placed next to each other. Please see the explanation for more detailed information.

A Double Star Cluster in Perseus
Image Credit & Copyright: Tommy Lease

This star cluster is close to each other. Hipparchus cataloged it in 130 BC and it is visible to the naked eye. This pair of open star cluster s is 7,000 light-years away and is an easy binocular target. The clusters are separated by a few hundred light-years and contain stars that are younger and hotter than the Sun. The age of the clusters is similar to that of the star-forming region, which is evidence that both clusters were created there.

Tomorrow's picture: open space

< | Archive | Submissions | Index | Search | Calendar | RSS | Education | About APOD | Discuss | >

Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
NASA Official: Phillip Newman Specific rights apply.
NASA Web Privacy Policy and Important Notices
A service of: ASD at NASA / GSFC,
NASA Science Activation
& Michigan Tech. U.