List of deep fields
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|image1=Hubble Legacy Field.png |caption1=Hubble Legacy Field{{cite web |title=Hubble Assembles Wide View of the Distant Universe |url=https://www.spacetelescope.org/news/heic1909/ |website=www.spacetelescope.org |accessdate=3 May 2019 |language=en}}
|image2=Deepfieldscomparison.jpg |caption2=Comparison of how far in the past some of the Hubble Space Telescope's deep fields have seen in terms of redshift and million years and also how far the James Webb Space Telescope should be able to see.
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In astronomy, a deep field is an image of a portion of the sky taken with a very long exposure time, in order to detect and study faint objects. The depth of the field refers to the apparent magnitude or the flux of the faintest objects that can be detected in the image. Deep field observations usually cover a small angular area on the sky, because of the large amounts of telescope time required to reach faint flux limits. Deep fields are used primarily to study galaxy evolution and the cosmic evolution of active galactic nuclei, and to detect faint objects at high redshift. Numerous ground-based and space-based observatories have taken deep-field observations at wavelengths spanning radio to X-rays.
The first deep-field image to receive a great deal of public attention was the Hubble Deep Field, observed in 1995 with the WFPC2 camera on the Hubble Space Telescope. Other space telescopes that have obtained deep-field observations include the Chandra X-ray Observatory, the XMM-Newton Observatory, the Spitzer Space Telescope, and the James Webb Space Telescope.
{{multiple images |total_width=600 |direction=horizontal |align=center |header=Left: image taken by Hubble (2017) vs Right: the image taken by Webb (2022){{cite news |last1=Chow |first1=Denise |last2=Wu |first2=Jiachuan |title=Photos: How pictures from the Webb telescope compare to Hubble's - NASA's $10 billion telescope peers deeper into space than ever, revealing previously undetectable details in the cosmos.|url=https://www.nbcnews.com/data-graphics/compare-photos-nasas-james-webb-space-telescope-hubble-space-telescope-rcna37875 |date=12 July 2022 |work=NBC News |accessdate=16 July 2022 }}
|image1=NASA-HubbleSpaceTelescope-DeepField-2017.jpg |image2=Webb's First Deep Field (adjusted).jpg
|footer=Deep Field – Galaxy cluster SMACS J0723.3-7327{{cite news |last=Garner |first=Rob |title=NASA's Webb Delivers Deepest Infrared Image of Universe Yet |url=https://www.nasa.gov/image-feature/goddard/2022/nasa-s-webb-delivers-deepest-infrared-image-of-universe-yet |date=11 July 2022 |work=NASA |accessdate=12 July 2022 |archive-date=12 July 2022 |archive-url=https://web.archive.org/web/20220712000119/https://www.nasa.gov/image-feature/goddard/2022/nasa-s-webb-delivers-deepest-infrared-image-of-universe-yet/ |url-status=live }}{{cite news |last1=Overbye |first1=Dennis |last2=Chang |first2=Kenneth |last3=Tankersley |first3=Jim |title=Biden and NASA Share First Webb Space Telescope Image – From the White House on Monday, humanity got its first glimpse of what the observatory in space has been seeing: a cluster of early galaxies. |url=https://www.nytimes.com/2022/07/11/science/nasa-webb-telescope-images-livestream.html |date=11 July 2022 |work=The New York Times |accessdate=12 July 2022 |archive-date=12 July 2022 |archive-url=https://web.archive.org/web/20220712005736/https://www.nytimes.com/2022/07/11/science/nasa-webb-telescope-images-livestream.html |url-status=live }}{{cite news |last=Pacucci |first=Fabio |title=How Taking Pictures of 'Nothing' Changed Astronomy - Deep-field images of "empty" regions of the sky from Webb and other space telescopes are revealing more of the universe than we ever thought possible |url=https://www.scientificamerican.com/article/how-taking-pictures-of-nothing-changed-astronomy1/ |date=15 July 2022|work=Scientific American |accessdate=16 July 2022 }}{{cite news |last1=Deliso |first1=Meredith |last2=Longo |first2=Meredith |last3=Rothenberg |first3=Nicolas |title=Hubble vs. James Webb telescope images: See the difference |url=https://abcnews.go.com/Technology/hubble-james-webb-telescope-images-difference/story?id=86763039 |date=14 July 2022 |work=ABC News |accessdate=15 July 2022 }}{{cite news |last=Kooser |first=Amanda |title=Hubble and James Webb Space Telescope Images Compared: See the Difference - The James Webb Space Telescope builds on Hubble's legacy with stunning new views of the cosmos. |url=https://www.cnet.com/pictures/hubble-and-james-webb-space-telescope-images-compared-see-the-difference/ |date=13 July 2012 |work=CNET |accessdate=16 July 2022 }}{{cite news |last=Atkinson |first=Nancy |title=Now, We can Finally Compare Webb to Other Infrared Observatories |url=https://www.universetoday.com/155686/now-we-can-finally-compare-webb-to-other-infrared-observatories/ |date=2 May 2022 |work=Universe Today |accessdate=12 May 2022 |archive-date=10 May 2022 |archive-url=https://web.archive.org/web/20220510035557/https://www.universetoday.com/155686/now-we-can-finally-compare-webb-to-other-infrared-observatories/ |url-status=live }}}}
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Table
The following table gives a partial list of deep-field observations taken since 1995.
See also
{{commonscat|Deep fields}}
References
{{reflist}}
{{Hubble Space Telescope}}
{{James Webb Space Telescope}}
{{NASA space program}}
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