April 25, 2016 - A Dark Galactic Dustball
A Dark Galactic Dustball Nine thousand light-years away in the constellation Cassiopeia, a pink glow from ionized hydrogen in the emission nebula NGC 281 provides an illuminated backdrop for an opaque cloud that lies in front of it. Once thought to be “holes in space,” these dark blotches are now understood to be clumps of condensing dust and gas within which stars eventually form. They are known as Bok globules, after the famously good-natured American astronomer Bart J. Bok, born in the Netherlands 110 years ago this week. Bok’s research focused on the evolution and structure of the Milky Way and the enigmatic dark clouds that now bear his name. With his wife, Priscilla, Bok wrote many popular astronomy books. He was also a renowned skeptic and debunker of astrology.
Image credit: NASA / ESA / The Hubble Heritage Team STScI/AURA)
Weekly Calendar
April 25 - May 1, 2016
Holidays - Sky Events - Space History
Monday 25
Mars 5° south of Moon
Saturn 3° south of Moon
1962: Second Block I Saturn C-1 (SA-2) launched
1990: Hubble Space Telescope deployed
2003: ISS Expedition Seven crew launched on Soyuz TMA-2
Tuesday 26
Juno at opposition
1920: Shapley-Curtis debate on the nature and distance of spiral nebulae
1993: STS-55 Columbia launched
Wednesday 27
Thursday 28
1900: Jan Oort born
1906: Bart Bok born
1928: Eugene Shoemaker born
1991: STS-39 Discovery launched
2001: Soyuz TM-32 launched; Dennis Tito becomes first space tourist
2003: GALEX launched
2006: CloudSat and CALIPSO launched
Friday 29
Last Qtr Moon 11:29 PM ET
Mercury appears stationary
1985: STS-51B Challenger launched
Saturday 30
Sunday 1
1949: Gerard Kuiper discovers Nereid, moon of Neptune
1996: Comet Hyakutake closest approach to Sun