June 24, 2013 - Cluster in a Cluster

Cluster in a Cluster A mere wingspan away from the nearby Eagle Nebula, the open star cluster NGC 6604 is often overlooked by skygazers in favor of its more prominent neighbor. NGC 6604, the bright cluster of young stars in the upper left of this image, is part of a larger and more widely scattered cluster of about one hundred brilliant blue-white stars known as Serpens OB. This image also shows the associated nebula Sh2-54, a diffuse cloud of ionized hydrogen gas, which is obscured in parts by dark dust lanes. The bright stars of NGC 6604, which lies about 5,500 light-years away in the constellation of Serpens, are easily seen in a small telescope and were first catalogued by William Herschel in 1784; however, the faint gas cloud escaped attention until the Palomar Sky Survey of the 1950s.

Image credit: ESO

Weekly Calendar

June 24-30, 2013

Holidays - Sky Events - Space History

Monday 24

St. Jean Baptiste Day (Québec)

1999: FUSE spacecraft launched

Tuesday 25

Mercury appears stationary

1894: Hermann Oberth born
1992: STS-50 Columbia launched
1997: Progress spacecraft collides with Mir Spektr module
1999: Gemini North telescope dedicated

Wednesday 26

1730: Charles Messier born
1963: Syncom 2 satellite launched
1984: First space shuttle launch pad abort (STS-41D)

Thursday 27

Neptune 6° south of Moon

1982: STS-4 Columbia launched
1995: STS-71 Atlantis launched
1997: NEAR-Shoemaker probe flies by asteroid Mathilde
2013: IRIS spacecraft launched

Friday 28

Saturday 29

1868: George Ellery Hale born
1961: Transit 4A launched, first nuclear-powered satellite
1971: Soyuz 11 crew dies during reentry

Sunday 30

Last Quarter Moon 12:54 AM ET
Uranus 4° south of Moon

1908: Tunguska impact levels hundreds of miles of Siberian forest
2001: WMAP spacecraft launched