Editing Quasar (section)

===Modern observations (1970s and onward)===
[[File:MUSE spies accreting giant structure around a quasar.tif|thumb|Cloud of gas around the distant quasar SDSS J102009.99+104002.7, taken by [[Multi-unit spectroscopic explorer|MUSE]]<ref>{{cite web |title=MUSE spies accreting giant structure around a quasar |url=http://www.eso.org/public/images/potw1747a/ |access-date=20 November 2017 |website=eso.org}}</ref>]]

Later it was found that not all quasars have strong radio emission; in fact only about 10% are "radio-loud". Hence the name "QSO" (quasi-stellar object) is used (in addition to "quasar") to refer to these objects, further categorized into the "radio-loud" and the "radio-quiet" classes. The discovery of the quasar had large implications for the field of astronomy in the 1960s, including drawing physics and astronomy closer together.<ref>{{cite journal |last1=de Swart |first1=J. G. |last2=Bertone |first2=G. |last3=van Dongen |first3=J. |title=How dark matter came to matter |journal=Nature Astronomy |date=2017 |volume=1 |issue=59 |pages=0059 |arxiv=1703.00013 |doi=10.1038/s41550-017-0059 |bibcode = 2017NatAs...1E..59D|s2cid=119092226 }}</ref>

In 1979, the [[gravitational lens]] effect predicted by [[Albert Einstein]]'s [[general theory of relativity]] was confirmed observationally for the first time with images of the [[Twin Quasar|double quasar]] 0957+561.<ref>{{cite web |url=http://www.astr.ua.edu/keel/agn/q0957.html |title=Active Galaxies and Quasars – Double Quasar 0957+561 |publisher=Astr.ua.edu |access-date=2011-07-01}}</ref>

[[File:UZC J224030.2+032131.jpg|thumb|A cosmic mirage known as the [[Einstein Cross]]. Four apparent images are actually from the same quasar.]]

A study published in February 2021 showed that there are more quasars in one direction (towards [[Hydra (constellation)|Hydra]]) than in the opposite direction, seemingly indicating that the Earth is moving in that direction. But the direction of this dipole is about 28° away from the direction of the Earth's motion relative to the [[cosmic microwave background]] radiation.<ref>{{cite journal |last=Secrest |first=Nathan |display-authors=etal |date=25 February 2021 |title=A Test of the Cosmological Principle with Quasars |journal=The Astrophysical Journal Letters |volume=908 |issue=2 |pages=L51 |arxiv=2009.14826 |bibcode=2021ApJ...908L..51S |doi=10.3847/2041-8213/abdd40 |doi-access=free}}</ref>

In March 2021, a collaboration of scientists, related to the [[Event Horizon Telescope]], presented, for the first time, a [[Polarization (waves)|polarized-based image]] of a [[black hole]], specifically the black hole at the center of [[Messier 87]], an [[elliptical galaxy]] approximately 55 million light-years away in the [[constellation]] [[Virgo (constellation)|Virgo]], revealing the forces giving rise to quasars.<ref name="NYT-20210324">{{cite news |last=Overbye |first=Dennis |authorlink=Dennis Overbye |title=The Most Intimate Portrait Yet of a Black Hole - Two years of analyzing the polarized light from a galaxy's giant black hole has given scientists a glimpse at how quasars might arise. |url=https://www.nytimes.com/2021/03/24/science/astronomy-messier-87-black-hole.html |archive-url=https://ghostarchive.org/archive/20211228/https://www.nytimes.com/2021/03/24/science/astronomy-messier-87-black-hole.html |archive-date=2021-12-28 |url-access=limited |date=24 March 2021 |work=[[The New York Times]] |accessdate=25 March 2021 }}{{cbignore}}</ref>