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

Monday 20

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

Tuesday 21

1866: Antonia Maury born
1965: Ranger 9 launched

Wednesday 22

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

Thursday 23

1749: Pierre Laplace born
1840: John William Draper takes first photograph of Moon
1912: Wernher von Braun born
1965: Gemini III launched
2001: Mir space station reenters atmosphere