GEMS - a rich trove of information about galaxy evolution

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Discussion Overview

The discussion revolves around the GEMS (Galaxy Evolution from Morphology and Spectroscopy) study, focusing on a newly released Hubble mosaic image that captures a significant area of the sky and provides insights into galaxy evolution. Participants explore various aspects of the study, including the implications of the findings, the technology behind the observations, and the potential for future research.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants express admiration for the Hubble image and the collaborative efforts of scientists, engineers, and astronauts involved in its creation and operation.
  • There is mention of the potential for using radiation techniques to assist in mapping galaxies, although specifics are not detailed.
  • One participant notes the size of the observed area, comparing it to the full moon, and speculates on the future evolution of the Milky Way as it may merge with Andromeda.
  • Another participant references a theoretical framework regarding the formation of elliptical galaxies through the slow merger of spiral galaxies, citing a review article on the topic.

Areas of Agreement / Disagreement

Participants generally express enthusiasm about the GEMS study and the Hubble image, but there are varying interpretations regarding the implications of the findings and the techniques discussed. No consensus is reached on the specifics of the radiation technique or the future of galaxy mergers.

Contextual Notes

Some discussions reference earlier posts and techniques that may not be fully explained within the current thread, leading to potential gaps in understanding the context of certain claims.

Who May Find This Useful

Readers interested in galaxy evolution, astronomical imaging, and the collaborative efforts in space science may find this discussion relevant.

Nereid
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A newly released mosaic image from Hubble, with 4 billion pixels, covering a square of sky about 1/2o wide, with an angular resolution of 0.05", and a depth of 24 or 25 mag.

"Not only does the GEMS study cover a large area at high resolution; it is also a three-dimensional map. Of the 60,000 or so galaxies that have been identified in the mosaic, distances have been found for 10,000 using another deep survey of the same area carried out with a 2.2-meter telescope at the European La Silla observatory in Chile."

"Jogee [a GEMS team member] looks forward to learning more about multiple-galaxy interactions, black-hole formation, the host galaxies of active galactic nuclei (of which there are about 80 in the survey), and mergers of spirals to become ellipticals. Of course, the observers work closely with theorists who devise ever-more-detailed computer simulations of the various physical processes that play a role in galactic evolution."

"This is becoming a very well-studied bit of sky. The GEMS field coincides with the extended Chandra Deep Field, which was imaged in X-rays by the Chandra X-Ray Observatory. The central fifth of the GEMS field is being imaged more deeply by the many-wavelength GOODS Survey. And within the GOODS area we will soon see will the smaller, deeper Hubble Ultra-Deep Field (UDF), the size of a single ACS camera frame. The UDF is currently scheduled for release in March."

http://skyandtelescope.com/news/article_1152_1.asp
 
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All I have to say about the image that I just saw on that news article is wow. My comments on it are such as:
1. Great Ideas had to go into this to make it happen.
2. Thanks should be handed out to all of the scientist and engineers that helped make this happen, and even a more special thanks to the astronauts that risked their lives up in space to create the Hubble telescope, and keep it operational for us.
3. Might they be able to use that Radiation technique that you were talking about in an earlier post to help them with the mapping of these galaxies and such according to the position of the earth?
-Bob Smith
 
Originally posted by ScionPunk352
All I have to say about the image that I just saw on that news article is wow. My comments on it are such as:
1. Great Ideas had to go into this to make it happen.
2. Thanks should be handed out to all of the scientist and engineers that helped make this happen, and even a more special thanks to the astronauts that risked their lives up in space to create the Hubble telescope, and keep it operational for us.
3. Might they be able to use that Radiation technique that you were talking about in an earlier post to help them with the mapping of these galaxies and such according to the position of the earth?
-Bob Smith
Glad to hear that you enjoyed this Bob, and welcome to Physics Forums.

re 3, would you mind pointing to which particular 'earlier post'? I'm afraid I sometimes lose track.
 
Ah, oh, my mistake, i got names confused. I saw Nareid, and Nibles, and i confused you two. Nibles had brought up something in this post that had something to do with the radiation of stars being used to track their positions in the universe.
 
Originally posted by Nereid
A newly released mosaic image from Hubble, with 4 billion pixels, covering a square of sky about 1/2o wide, with an angular resolution of 0.05", and a depth of 24 or 25 mag.

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Hey Nereid, half a degree wide is the size of the full moon
a pretty nice size patch of sky!

so ellipticals form by the slow merger of spirals
and Milky may someday be one (after consuming Andromeda?)

wish I had a poster of that GEMS picture to put on the study wall.
thanks
 


Originally posted by marcus
so ellipticals form by the slow merger of spirals

This has been theorized by astronomers studying the formation of globular clusters. See this review article, for example:

http://arxiv.org/abs/astro-ph/0107297
 

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