Editing Hubble Space Telescope (section)

=== Proposals and precursors ===
[[File:Astronaut Owen Garriott Performs EVA During Skylab 3 - GPN-2002-000065.jpg|thumb|upright|left|Astronaut [[Owen Garriott]] working next to Skylab's crewed solar space observatory, 1973]]

In 1923, [[Hermann Oberth]]—considered a father of modern rocketry, along with [[Robert H. Goddard]] and [[Konstantin Tsiolkovsky]]—published ''{{lang|de|[[Die Rakete zu den Planetenräumen]]}}'' ("The Rocket into Planetary Space"), which mentioned how a telescope could be propelled into [[Earth]] orbit by a rocket.<ref>{{cite book |last=Oberth |first=Hermann |title=Die Rakete zu den Planetenräumen |date=1923 |publisher=R. Oldenbourg-Verlay |page=85 |language=de}}</ref>

[[File:1946- Lyman Spitzer (4526166350).jpg|thumb|right|upright|[[Lyman Spitzer]] played a major role in the birth of the Hubble Space Telescope project.|alt=[[Lyman Spitzer]] played a major role in the birth of the Hubble Space Telescope project.]]
The history of the Hubble Space Telescope can be traced to 1946, to [[astronomer]] [[Lyman Spitzer]]'s paper "Astronomical advantages of an extraterrestrial observatory".<ref name=":0">Spitzer, Lyman Jr., "Report to Project Rand: Astronomical Advantages of an Extra-Terrestrial Observatory", reprinted in [https://history.nasa.gov/SP-4407/vol5/ExploreUnknown.pdf ''NASA SP-2001-4407: Exploring the Unknown''] {{Webarchive|url=https://web.archive.org/web/20170120024958/https://history.nasa.gov/SP-4407/vol5/ExploreUnknown.pdf |date=January 20, 2017 }}, Chapter 3, Document III-1, p. 546.</ref> In it, he discussed the two main advantages that a space-based observatory would have over ground-based telescopes. First, the [[angular resolution]] (the smallest separation at which objects can be clearly distinguished) would be limited only by [[Diffraction-limited system|diffraction]], rather than by the turbulence in the atmosphere, which causes stars to twinkle, known to astronomers as [[astronomical seeing|seeing]]. At that time ground-based telescopes were limited to resolutions of 0.5–1.0 [[arcsecond]]s, compared to a theoretical diffraction-limited resolution of about 0.05 arcsec for an optical telescope with a [[mirror]] {{cvt|2.5|m}} in diameter. Second, a space-based telescope could observe [[infrared]] and ultraviolet light, which are strongly absorbed by the [[atmosphere of Earth]].<ref name=":0" />

Spitzer devoted much of his career to pushing for the development of a space telescope.<ref>{{Cite web|title=Celebrating Lyman Spitzer, the father of PPPL and the Hubble Space Telescope|url=https://research.princeton.edu/news/celebrating-lyman-spitzer-father-pppl-and-hubble-space-telescope|access-date=December 4, 2021|website=Office of the Dean for Research|archive-date=December 7, 2021|archive-url=https://web.archive.org/web/20211207155008/https://research.princeton.edu/news/celebrating-lyman-spitzer-father-pppl-and-hubble-space-telescope|url-status=live}}</ref> In 1962, a report by the U.S. [[National Academy of Sciences]] recommended development of a [[space telescope]] as part of the [[Human spaceflight|space program]], and in 1965, Spitzer was appointed as head of a committee given the task of defining scientific objectives for a large space telescope.<ref>{{cite web |url=http://www.spitzer.caltech.edu/about/spitzer.shtml|title=About Lyman Spitzer, Jr|publisher=Caltech|access-date=April 26, 2008|archive-url=https://web.archive.org/web/20080327091202/http://www.spitzer.caltech.edu/about/spitzer.shtml|archive-date=March 27, 2008}}</ref>

[[File:Nancy Grace Roman with Space Telescope Model in 1966 (27154772837).jpg|thumb|upright|[[Nancy Grace Roman]] with a model of the Large Space Telescope that was eventually developed as the Hubble Space Telescope. While listed as a 1966 photo, this design was not the standard until the mid-1970s.]]
Also crucial was the work of [[Nancy Roman|Nancy Grace Roman]], the "Mother of Hubble".<ref>{{Cite web|last=Smith|first=Yvette|date=May 15, 2020|title=Nancy Grace Roman: The Mother of Hubble|url=http://www.nasa.gov/image-feature/nancy-grace-roman-the-mother-of-hubble-2|access-date=December 4, 2021|website=NASA|archive-date=December 7, 2021|archive-url=https://web.archive.org/web/20211207160733/https://www.nasa.gov/image-feature/nancy-grace-roman-the-mother-of-hubble-2/|url-status=live}}</ref> Well before it became an official [[NASA]] project, she gave public lectures touting the scientific value of the telescope. After it was approved, she became the program scientist, setting up the steering committee in charge of making astronomer needs feasible to implement<ref>{{Cite web|title=Explorer 1 {{!}} Stories {{!}} Nancy Grace Roman|url=https://explorer1.jpl.nasa.gov/stories/nancy-grace-roman/|access-date=December 4, 2021|website=explorer1.jpl.nasa.gov|archive-date=May 31, 2022|archive-url=https://web.archive.org/web/20220531015937/https://explorer1.jpl.nasa.gov/stories/nancy-grace-roman/|url-status=live}}</ref> and writing testimony to [[United States Congress|Congress]] throughout the 1970s to advocate continued funding of the telescope.<ref name=AnnRev>{{Cite journal |author= Roman, Nancy Grace |title= Nancy Grace Roman and the Dawn of Space Astronomy |journal= Annual Review of Astronomy and Astrophysics |volume= 57 |pages= 1–34 |year= 2019 |doi= 10.1146/annurev-astro-091918-104446 |bibcode= 2019ARA&A..57....1R |doi-access= free}}</ref> Her work as project scientist helped set the standards for NASA's operation of large scientific projects.<ref name=WilliamsBook>{{cite book |last= Williams |first= Robert |date= October 1, 2018 |title= Hubble Deep Field and the Distant Universe |url= https://iopscience.iop.org/book/978-0-7503-1756-6 |location= Bristol, UK |publisher= IOP Publishing |pages= 2–9 |isbn= 978-0-7503-1756-6 |archive-date= June 5, 2020 |archive-url= https://web.archive.org/web/20200605012705/https://iopscience.iop.org/book/978-0-7503-1756-6 |url-status= live}}</ref>

Space-based astronomy had begun on a very small scale following [[World War II]], as scientists made use of developments that had taken place in [[rocket]] technology. The first ultraviolet [[electromagnetic spectrum|spectrum]] of the [[Sun]] was obtained in 1946,<ref>{{cite journal|title=Solar Ultraviolet Spectrum to 88 Kilometers|last1=Baum |first1=W. A.|display-authors=4|last2=Johnson |first2=F. S.|last3=Oberly |first3=J. J. |last4=Rockwood |first4=C. C.|last5=Strain |first5=C. V.|last6=Tousey |first6=R.|journal=Physical Review|volume=70|pages=781–782|date=November 1946|doi=10.1103/PhysRev.70.781|issue=9–10 |bibcode=1946PhRv...70..781B}}</ref> and NASA launched the [[Orbiting Solar Observatory]] (OSO) to obtain UV, X-ray, and gamma-ray spectra in 1962.<ref>{{cite web|url=https://heasarc.gsfc.nasa.gov/docs/heasarc/missions/oso1.html|title=The First Orbiting Solar Observatory|date=June 26, 2003|work=heasarc.gsfc.nasa.gov|publisher=NASA Goddard Space Flight Center|access-date=September 25, 2011|archive-date=May 3, 2019|archive-url=https://web.archive.org/web/20190503001707/https://heasarc.gsfc.nasa.gov/docs/heasarc/missions/oso1.html|url-status=live}} {{PD-notice}}</ref> An [[Ariel 1|orbiting solar telescope]] was launched in 1962 by the United Kingdom as part of the [[Ariel programme]], and in 1966 [[NASA]] launched the first [[Orbiting Astronomical Observatory]] (OAO) mission. OAO-1's battery failed after three days, terminating the mission. It was followed by [[Orbiting Astronomical Observatory 2]] (OAO-2), which carried out ultraviolet observations of [[star]]s and [[galaxy|galaxies]] from its launch in 1968 until 1972, well beyond its original planned lifetime of one year.<ref>{{cite web |url=http://nasascience.nasa.gov/missions/oao|title=OAO|publisher=NASA|access-date=April 26, 2008|url-status=dead|archive-url=https://web.archive.org/web/20080916121848/http://nasascience.nasa.gov/missions/oao |archive-date=September 16, 2008}} {{PD-notice}}</ref>

The OSO and OAO missions demonstrated the important role space-based observations could play in astronomy. In 1968, NASA developed firm plans for a space-based [[reflecting telescope]] with a mirror {{cvt|3|m}} in diameter, known provisionally as the Large Orbiting Telescope or Large Space Telescope (LST), with a launch slated for 1979. These plans emphasized the need for crewed maintenance missions to the telescope to ensure such a costly program had a lengthy working life, and the concurrent development of plans for the reusable [[Space Shuttle]] indicated that the technology to allow this was soon to become available.{{sfn|Spitzer|1979|p=32}}