File:Stacks of Light.jpg

Original file (5,100 × 2,550 pixels, file size: 2.97 MB, MIME type: image/jpeg)

Captions

English

Add a one-line explanation of what this file represents

Summary

DescriptionStacks of Light.jpg	English: These two images show "stacked" Chandra images for two different classes of distant, massive galaxy detected with Spitzer. Image stacking is a procedure used to detect emission from objects that is too faint to be detected in single images. To enhance the signal, images of these faint objects are stacked on top of one another. In both images, low-energy X-rays are shown in orange and high-energy X-rays in blue, and the stacked object is in the center of the image (the other sources beyond the center of the image are X-ray sources that were directly detected and are not part of the source stacking). On the left is a stacked Chandra image of the "normal" galaxies seen with Spitzer. The infrared emission for these young, massive galaxies is consistent with expectations for star formation. The Chandra image shows mainly low-energy X-ray emission at the center as expected. On the right, is a stacked Chandra image for galaxies with infrared emission exceeding the levels likely to be caused by star formation. These galaxies contain active galactic nuclei, or quasars, in their centers. These are luminous objects powered by the rapid growth of supermassive black holes. The obscured quasars show much higher levels of high-energy X-ray emission because the less energetic X-rays are mostly absorbed by gas.
Date	25 October 2007
Source	http://www.spitzer.caltech.edu/images/2668-ssc2007-17b-Stacks-of-Light
Author	NASA/CXC/Durham/D.Alexander et al.

Image use policy: http://www.spitzer.caltech.edu/info/18-Image-Use-Policy

Licensing

	This file is in the public domain in the United States because it was solely created by NASA. NASA copyright policy states that "NASA material is not protected by copyright unless noted". (See Template:PD-USGov, NASA copyright policy page or JPL Image Use Policy.)
	Warnings: Use of NASA logos, insignia and emblems is restricted per U.S. law 14 CFR 1221. The NASA website hosts a large number of images from the Soviet/Russian space agency, and other non-American space agencies. These are not necessarily in the public domain. Materials based on Hubble Space Telescope data may be copyrighted if they are not explicitly produced by the STScI.[1] See also {{PD-Hubble}} and {{Cc-Hubble}}. The SOHO (ESA & NASA) joint project implies that all materials created by its probe are copyrighted and require permission for commercial non-educational use. [2] Images featured on the Astronomy Picture of the Day (APOD) web site may be copyrighted. [3] The National Space Science Data Center (NSSDC) site has been known to host copyrighted content. Its photo gallery FAQ states that all of the images in the photo gallery are in the public domain "Unless otherwise noted."

File history

Click on a date/time to view the file as it appeared at that time.

	Date/Time	Thumbnail	Dimensions	User	Comment
current	20:03, 14 June 2011		5,100 × 2,550 (2.97 MB)	Spitzersteph (talk \| contribs)

You cannot overwrite this file.

File usage on Commons

There are no pages that use this file.

File usage on other wikis

The following other wikis use this file:

Usage on en.wikiversity.org
- User:Marshallsumter/Radiation astronomy/Active galactic nuclei

Metadata

This file contains additional information such as Exif metadata which may have been added by the digital camera, scanner, or software program used to create or digitize it. If the file has been modified from its original state, some details such as the timestamp may not fully reflect those of the original file. The timestamp is only as accurate as the clock in the camera, and it may be completely wrong.

Image title	These two images show "stacked" Chandra images for two different classes of distant, massive galaxy detected with Spitzer. Image stacking is a procedure used to detect emission from objects that is too faint to be detected in single images. To enhance the signal, images of these faint objects are stacked on top of one another. In both images, low-energy X-rays are shown in orange and high-energy X-rays in blue, and the stacked object is in the center of the image (the other sources beyond the center of the image are X-ray sources that were directly detected and are not part of the source stacking). On the left is a stacked Chandra image of the "normal" galaxies seen with Spitzer. The infrared emission for these young, massive galaxies is consistent with expectations for star formation. The Chandra image shows mainly low-energy X-ray emission at the center as expected. On the right, is a stacked Chandra image for galaxies with infrared emission exceeding the levels likely to be caused by star formation. These galaxies contain active galactic nuclei, or quasars, in their centers. These are luminous objects powered by the rapid growth of supermassive black holes. The obscured quasars show much higher levels of high-energy X-ray emission because the less energetic X-rays are mostly absorbed by gas.
Copyright holder	http://www.spitzer.caltech.edu/Media/mediaimages/copyright.shtml
Width	5,100 px
Height	2,550 px
Compression scheme	LZW
Pixel composition	RGB
Orientation	Normal
Number of components	3
Horizontal resolution	300 dpi
Vertical resolution	300 dpi
Data arrangement	chunky format
Software used	Adobe Photoshop CS3 Macintosh
File change date and time	11:43, 23 July 2009
Color space	Uncalibrated

File:Stacks of Light.jpg

Captions

Captions

Summary

Licensing

File history

File usage on Commons

File usage on other wikis

Metadata

Structured data

Items portrayed in this file

depicts

copyright status

public domain

inception

25 October 2007

Navigation menu

File:Stacks of Light.jpg

Captions

Captions

Summary

Licensing

File history

File usage on Commons

File usage on other wikis

Metadata

Navigation menu

Search