Comparing APEX and ALMA views of star-forming galaxies in the early Universe

A team of astronomers has used ALMA (the Atacama Large Millimeter/submillimeter Array) to pinpoint the locations of over 100 of the most fertile star-forming galaxies in the early Universe.

The best map so far of these distant dusty galaxies was made using the Atacama Pathfinder Experiment (APEX), but the observations were not sharp enough to unambiguously identify these galaxies in images at other wavelengths. ALMA needed just two minutes per galaxy to pinpoint each one within a comparatively tiny region 200 times smaller than the broad APEX blobs, and with three times the sensitivity.

This video zooms in on some of the galaxies. The large red blobs are the earlier APEX observations and the much sharper views are from ALMA. Whereas the APEX images were not sharp enough to identify the emitting galaxies unambiguously the much sharper ALMA images can pin down the emitting galaxies much more precisely. The ALMA and APEX observations, at submillimetre wavelengths, are overlaid on an infrared view of the region as seen by the IRAC camera on the Spitzer Space Telescope (coloured blue). 


ALMA (ESO/NAOJ/NRAO), APEX (MPIfR/ESO/OSO), J. Hodge et al., A. Weiss et al., NASA Spitzer Science Center

About the Video

Release date:17 April 2013, 12:00
Related releases:eso1318
Duration:41 s
Frame rate:30 fps

About the Object

Name:Chandra Deep Field South, Galaxies
Type:Unspecified : Galaxy



Large QT
3.2 MB


Video Podcast
2.8 MB
Medium MPEG-1
16.6 MB
Medium Flash
3.9 MB


Small Flash
2.0 MB
Small QT
1.3 MB

For Broadcasters