January 4, 2016 - Galaxies Swim in the Ghostly Light of Castaway Stars
Galaxies Swim in the Ghostly Light of Castaway Stars An enormous cluster of colliding galaxies four billion light-years away is surrounded by the faint glow of stars that have been torn from their home galaxies in this near-infrared image acquired by the Hubble Space Telescope as part of the Frontier Fields program. The galaxy cluster is called Abell 2744—also known as Pandora’s Cluster—and contains 500 galaxies which together have the equivalent mass of four trillion Suns. Powerful gravitational forces within the cluster are thought to have ripped apart six Milky Way-sized galaxies over the course of six billion years, scattering orphaned stars across intergalactic space. Their dim light is visible to Hubble in near-infrared wavelengths, colored blue in the view above.
Image credit: NASA / ESA / M. Montes (IAC) / J. Lotz / M. Mountain / A. Koekemoer / HFF Team (STScI).
Weekly Calendar
January 4-10, 2016
Holidays - Sky Events - Space History
Monday 4
Quadrantid meteor shower
1970: NASA cancels Apollo 20 mission; further production of Saturn V launch vehicles ceases
Tuesday 5
Mercury appears stationary
Pluto in conjunction with Sun
1969: Venera 5 launched
1972: President Nixon announces approval to develop the Space Shuttle
2005: UB313 (Eris) discovered, ignites the Pluto-Planet debate
Wednesday 6
Epiphany
Venus 6° north of Antares
Venus 3° south of Moon
1998: Lunar Prospector launched
Thursday 7
Saturn 3° south of Moon
1610: Galileo discovers Callisto, Europa, & Io
1964: First power tool for space demonstrated
1968: Surveyor 7 launched
Friday 8
Jupiter appears stationary
Venus 0.09° north of Saturn
1587: Johann Fabricius born
1942: Stephen Hawking born
1973: Luna 21 & Lunokhod 2 launched
1987: Challenger debris buried
Saturday 9
New Moon 8:30 PM ET
1839: Thomas Henderson publishes distance to Alpha Centauri
1968: Surveyor 7 lands on Moon
1990: STS-32 Columbia launched
Sunday 10
1946: U.S. Army bounces radar signal off the Moon
1969: Venera 6 launched