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.

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.[2] 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.

Left: image taken by Hubble (2017) vs Right: the image taken by Webb (2022)[3]


The following table gives a partial list of deep-field observations taken since 1995.

Image Name Year captured Size (arcminute) Number of exposures
Hubble Deep Field 1995 2.6′x2.6′ 342
Hubble Deep Field South 1998 5.3²′ 995
Chandra Deep Field South 1999–2000 16′ across 11
Hubble Ultra-Deep Field 2003–2004 2.4′x2.4′ 808
Extended Groth Strip 2004–2005 70′x10′ over 500
Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) 2011
ESO’s VLT and the SINFONI instrument[9] 2012
Hubble eXtreme Deep Field 2012 2.3′x3′
Hubble Ultra-Deep Field (UV/VIS/NIR) 2014
Hubble Frontier Fields MACS J0416.1-2403[10] 2015
Hubble Frontier Fields Abell 2744[11] 2015
Hubble Frontier Fields MACS J0717.5+3745 2015
Hubble Frontier Fields MACS J1149.5+2223[12] 2015
Hubble Frontier Fields Abell S1063[13] 2016
Hubble Frontier Fields Abell 370[14] 2017
Hubble Frontier Fields Abell 370 parallel field[15] 2017
Hubble Deep UV (HDUV) Legacy Survey[16] 2018
Hubble Legacy Field[1] 2019 25′x25′ 7,500
Dark Energy Survey[17][18] 2021 18.41′x9.64′
Webb's First Deep Field 2022 2.4′ across
James Webb Space Telescope – JADES (James Webb Space Telescope Advanced Deep Extragalactic Survey)
First Deep Field[19][20]
2022 ??′ across

See also


  1. ^ a b "Hubble Assembles Wide View of the Distant Universe". Retrieved 3 May 2019.
  2. ^ a b Pacucci, Fabio (15 July 2022). "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". Scientific American. Retrieved 16 July 2022.
  3. ^ Chow, Denise; Wu, Jiachuan (12 July 2022). "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". NBC News. Retrieved 16 July 2022.
  4. ^ Garner, Rob (11 July 2022). "NASA's Webb Delivers Deepest Infrared Image of Universe Yet". NASA. Archived from the original on 12 July 2022. Retrieved 12 July 2022.
  5. ^ Overbye, Dennis; Chang, Kenneth; Tankersley, Jim (11 July 2022). "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". The New York Times. Archived from the original on 12 July 2022. Retrieved 12 July 2022.
  6. ^ Deliso, Meredith; Longo, Meredith; Rothenberg, Nicolas (14 July 2022). "Hubble vs. James Webb telescope images: See the difference". ABC News. Retrieved 15 July 2022.
  7. ^ Kooser, Amanda (13 July 2012). "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". CNET. Retrieved 16 July 2022.
  8. ^ Atkinson, Nancy (2 May 2022). "Now, We can Finally Compare Webb to Other Infrared Observatories". Universe Today. Archived from the original on 10 May 2022. Retrieved 12 May 2022.
  9. ^ "The Feeding Habits of Teenage Galaxies". ESO Press Release. Retrieved 16 March 2012.
  10. ^ Vogel, Tracy (21 January 2015). "MACS J0416 Data is Complete". Frontier Fields. Retrieved 24 Nov 2015.
  11. ^ "Meet the Frontier Fields: Abell 2744". Frontier Fields. 4 February 2014. Retrieved 24 Nov 2015.
  12. ^ "A galactic gathering". Retrieved 23 May 2016.
  13. ^ "Space... the final frontier". Retrieved 25 July 2016.
  14. ^ "Abell 370". Retrieved 21 Jun 2018.
  15. ^ "Abell 370 parallel field". Retrieved 21 Jun 2018.
  16. ^ Jenkins, Ann; Villard, Ray; Oesch, Pascal; Montes, Mireia; Hille, Karl (16 August 2018). "NASA - Hubble Paints Picture of the Evolving Universe". NASA. Retrieved 17 August 2018.
  17. ^ "Dark Energy Survey Releases Most Precise Look at the Universe's Evolution - First three years of survey data uses observations of 226 million galaxies over ⅛ of the sky".
  18. ^ "Dark Energy Survey deep field image".
  19. ^ Gough, Evan (12 December 2022). "Webb Completes its First "Deep Field" With Nine Days of Observing Time. What did it Find?". Universe Today. Retrieved 13 December 2022.
  20. ^ Downer, Bethany (9 December 2022). "NASA's Webb Reaches New Milestone in Quest for Distant Galaxies". NASA. Retrieved 13 December 2022.