21. Scutum also boasts a couple of fine star clusters . 22. Serpens South is a star cluster embedded in a dense molecular filament containing numerous protostars. 23. Delta Cephei, the prototypical classical Cepheid variables, is also a member of a star cluster . 24. In 2005, astronomers discovered a completely new type of star cluster in the Andromeda Galaxy. 25. He discovered or rediscovered three open star clusters , Westerlund 1, Westerlund 2 and Westerlund 3. 26. This star cluster is estimated to be around two and a half million years old. 27. He also led an expedition to Chile in 1882 to observe the Hyades star cluster . 28. There is no systematic bias in the Hipparcos data when it comes to star clusters . 29. The objects are in a star cluster field called Sigma Orionis within the constellation Orion. 30. Located 7200 light years away, the Wizard nebula, surrounds developing open star cluster NGC 7380.
