Catalogs of distant, faint sources dark fields [rejected]

Aug 21, 2013
This image of a "dark field" was taken by the Great Observatories Origins Deep Survey project using NASA's Hubble Space Telescope. The full program has just released a multi-wavelength catalog of 34,930 galaxies, enabling astronomers to study the evolution of galaxies in the early universe. Credit: NASA, HST, and the CANDELS team

Over the past decade, the Hubble Space Telescope (HST) and other modern, giant telescopes have opened a new era in observational cosmology. By staring for long times at so-called "dark fields"—regions of the sky without much background emission from the solar system or the galaxy—astronomers have been able to detect very faint galaxies in the early universe, and to study their evolution from early stages to the present. More recently, deep multi-wavelength imaging surveys have been undertaken, and have revealed a complex interplay between galaxy mergers, star formation, and black holes over cosmic time, leading to new insights into the physical processes that drive galaxy formation and evolution.

From the entire span of cosmic time, two epochs are particularly of great interest: "cosmic high noon," from which period light has been traveling for about ten billion years, and "" with much older galaxies whose light has been en route to us for about thirteen billion years. During the former period, cosmic star formation activity reached its peak; the latter period is when in the cosmos became ionized.

CfA astronomers Giovanni Fazio, Steve Willner, and Matt Ashby are the PI and key team leaders, respectively, of the Spitzer Infrared Array Camera (IRAC). Along with a large team of colleagues, they have just published a multi-wavelength catalog—from the ultraviolet to the infrared—of 34,930 galaxies spanning the cosmic high noon and cosmic dawn taken with IRAC, HST, and other telescopes in the direction of five popular "dark fields."

The large sample of remote systems is called CANDELS (The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey). It is able to detect star forming galaxies smaller than our Milky Way at these huge distances with a 50% completeness level, and more passive, fainter galaxies with somewhat less sensitivity. The new catalog makes it possible to study for the first time with statistical precision how galaxies evolved in the universe into predominantly two kinds: bluish, active spiral galaxies, and red, passive elliptical galaxies.

Explore further: Kepler proves it can still find planets

More information: Guo, Y. et al. Candels Multi-Wavelength Catalogs: Source Detection and Photometry in the Goods-South Field, ApJS, 207, 24, 2013.

add to favorites email to friend print save as pdf

Related Stories

The distant cosmos as seen in the infrared

Apr 12, 2013

(Phys.org) —At some stage after its birth in the big bang, the universe began to make galaxies. No one knows exactly when, or how, this occurred. For that matter, astronomers do not know how the lineages ...

Galaxies the way they were

Apr 03, 2013

(Phys.org) —Galaxies today come very roughly in two types: reddish, elliptically shaped collections of older stars, and bluer, spiral shaped objects dominated by young stars. The conventional wisdom is ...

Galaxies in the young cosmos

May 21, 2012

(Phys.org) -- The universe was born about 13.7 billion years ago in the big bang. The Sun and its system of planets formed about five billion years ago. What happened, then, during that long, intervening stretch ...

The cosmic infrared background

Aug 13, 2012

(Phys.org) -- The cosmic infrared background is the collective infrared radiation emitted by cosmic sources throughout the history of the universe, including sources inaccessible to current telescopes. The ...

Recommended for you

Kepler proves it can still find planets

5 minutes ago

To paraphrase Mark Twain, the report of the Kepler spacecraft's death was greatly exaggerated. Despite a malfunction that ended its primary mission in May 2013, Kepler is still alive and working. The evidence ...

The hot blue stars of Messier 47

Dec 17, 2014

Messier 47 is located approximately 1600 light-years from Earth, in the constellation of Puppis (the poop deck of the mythological ship Argo). It was first noticed some time before 1654 by Italian astronomer ...

User comments : 4

Adjust slider to filter visible comments by rank

Display comments: newest first

jsdarkdestruction
1 / 5 (1) Aug 21, 2013
why does it say [rejected] in/after the title?
Q-Star
4 / 5 (4) Aug 21, 2013
why does it say [rejected] in/after the title?


I'm curious about too. The vote here in the office is that it has nothing to do with the "Catalogs" and is an editor's markup for the article about the "Catalogs"
Eoprime
1 / 5 (1) Aug 26, 2013
why does it say [rejected] in/after the title?


I'm curious about too. The vote here in the office is that it has nothing to do with the "Catalogs" and is an editor's markup for the article about the "Catalogs"


I think too, it just should't have been published, like the GB or US newspaper with the 'testsite' on their homefrontpage with the funny catpic ;)
antialias_physorg
1 / 5 (1) Aug 26, 2013
The vote here in the office is that it has nothing to do with the "Catalogs" and is an editor's markup for the article about the "Catalogs"


The fun thing is if you google for the full title (including the 'rejected') you'll find it quoted on many other sites which cite physorg as their source.

If you google just the title you'll find that physorg probably sourced it from here
http://www.cfa.ha...328.html
which doesn't include the 'rejected' markup.

So my knee-jerk analysis would be that this is a physorg markup (possibly misspelled/misformatted since it got through any automatic filter looking for the tag)

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.