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March 20, 2017 - Galactic Frontiers

Galactic Frontiers  Galaxy clusters are enormous collections of hundreds or thousands of galaxies and vast reservoirs of hot gas embedded in massive clouds of dark matter. Six of these giant clusters are the focus of the Frontier Fields study, a multi-wavelength effort using the world’s most powerful telescopes to understand how our universe evolved and where it may be heading. Seen here, MACS J0416 is a pair of colliding galaxy clusters 4.3 billion light-years away that will eventually combine to form an even bigger cluster (nearly every object in this image is a galaxy). This image contains data in the X-ray (diffuse emission in blue), optical (red, green, and blue), and the radio (diffuse emission in pink) portions of the spectrum. Galaxies optically distorted by gravitational lensing appear as long arcs.

Image credit: NASA, ESA, CXC, NRAO/AUI/NSF, STScI, R. van Weeren (Harvard-Smithsonian CfA), G. Ogrean (Stanford)

Weekly Calendar

March 20-26, 2017

Holidays - Sky Events - Space History


Moon phase Monday 20

Equinox 6:29 AM ET
Saturn 3° south of Moon
Last Qtr Moon 11:58 AM ET

Moon phase Tuesday 21

1866: Antonia Maury born
: Ranger 9 launched

Moon phase Wednesday 22

1982: STS-3 Columbia launched
1996: STS-76 Atlantis launched
1997: Comet Hale-Bopp closest approach to Earth

Moon phase Thursday 23

1749: Pierre Laplace born
: John William Draper takes first photograph of Moon
1912: Wernher von Braun born
1965: Gemini III launched
2001: Mir space station reenters atmosphere

Moon phase Friday 24

1893: Walter Baade born
1992: STS-45 Atlantis launched

Moon phase Saturday 25

Venus in inferior conjunction

1655: Christiaan Huygens discovers Titan, moon of Saturn
1996: Comet Hyakutake closest approach to Earth
2000: IMAGE spacecraft launched

Moon phase Sunday 26

Neptune 0.005° north of Moon

2009: Soyuz TMA-14 launched carrying ISS Expedition 19/20 crew

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