miscellaneous


NGC 869 / NGC 884

NGC 869 (h) and NGC 884 (χ) are two open clusters located 7,600 light years away in the constellation of Perseus. The clusters are most likely around 13 million years old. NGC 869 is the westernmost of the Double Cluster. NGC 869 and 884 are often designated h and χ Persei, respectively. Some confusion surrounds what Bayer intended by these designations. It is sometimes claimed that Bayer could not have resolved the pair into two patches of nebulosity, and that χ refers to the Double Cluster and h to a nearby star. Bayer's Uranometria chart for Perseus does not show them as nebulous objects, but his chart for Cassiopeia does, and they are described as Nebulosa Duplex in Schiller's Coelum Stellatum Christianum, which was assembled with Bayer's help. The clusters are both located in the Perseus OB1 association, a few hundred light years apart from each other.

(Source: Wikipedia)


NGC 2903 / NGC 2905

NGC 2903 is a barred spiral galaxy about 30 million light-years away in the constellation Leo. It was discovered by William Herschel who cataloged it on November 16, 1784. NGC 2905 is a bright star cloud within this galaxy. NGC 2903 has a very high speed of creating new stars in the central region and is part of the Virgo Supercluster.

(Source: Wikipedia)