The Daily Hubble Top 100 Images - #95 Unusual Spiral NGC 4921 in the Coma Galaxy Cluster This very deep image shows the spiral galaxy NGC 4921 along with a spectacular backdrop of more distant galaxies. Credit: NASA, ESA and K. Cook (Lawrence Livermore National Laboratory, USA)
The Helix Nebula, lies 650 light-years away, in the constellation of Aquarius. It is a typical example of a class of objects called planetary nebula. Planetary nebulae are actually the remains of stars that once looked a lot like our sun. These stars spend most of their lives turning hydrogen into helium in massive runaway nuclear fusion reactions in their cores. In fact, this process of fusion provides all the light and heat that we get from our sun.
The star cluster Pismis 24 lies in the core of the large emission nebula NGC 6357 that extends one degree on the sky in the direction of the Scorpius constellation. | Credit: NASA, ESA and Jesús Maíz Apellániz (Instituto de Astrofísica de Andalucía, Spain). Acknowledgement: Davide De Martin (ESA/Hubble)