August 27, 2012 - Far-Out Galactic Interactions

Far-Out Galactic Interactions In April 2011, astronomers pointed the Hubble Space Telescope at an especially photogenic pair of interacting galaxies called Arp 273. The larger spiral galaxy, known as UGC 1810, has a disk that is distorted into a rosette shape by the gravitational tidal pull of the companion galaxy below it, known as UGC 1813. A swath of blue jewel-like points across the top is the combined light from clusters of intensely bright and hot young blue stars. These massive stars glow fiercely in ultraviolet light. The smaller, nearly edge-on companion shows distinct signs of intense star formation at its nucleus, perhaps triggered by the encounter with the companion galaxy. Arp 273 lies in the constellation Andromeda and is roughly 300 million light-years away from Earth.

Image credit: NASA / ESA / Hubble Heritage Team (STScI/AURA)

Weekly Calendar

August 27 - September 2, 2012

Holidays - Sky Events - Space History

Moon phase Monday 27

1962: Mariner 2 launched
1984: Teacher In Space program announced
1985: STS-51I Discovery launched

Moon phase Tuesday 28

1789: William Herschel discovers Enceladus, moon of Saturn
1993: Galileo spacecraft flies by asteroid Ida
2009: STS-128 Discovery launched

Moon phase Wednesday 29

Moon phase Thursday 30

1963: Lunar Orbiter program approved by NASA
1983: STS-8 Challenger launched
1984: STS-41D Discovery launched

Moon phase Friday 31

Neptune 6° south of Moon
Full Moon 9:58 AM ET

Moon phase Saturday 1

Venus 9° south of Pollux

1964: First Titan IIIA launched
1979: Pioneer 11 becomes first spacecraft to fly past Saturn

Moon phase Sunday 2

Uranus 5° south of Moon

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