Editing BL Lacertae object (section)

==History==

[[Image:H0323bl2.gif|thumb|right|The BL Lac object H 0323+022 (z=0.147) imaged at ESO NTT (R filter).
The host galaxy and close companions are visible.]]

John L. Schmitt first noticed the peculiar nature of BL Lac in 1968 when he matched it with a radio object, VRO 42.22.01.<ref name="schmitt1968">{{cite journal |title=''BL Lac'' identified as a Radio Source |journal=Nature |first1=John L. |last1=Schmitt |volume=218 |date=May 1968 |page=663 |bibcode=1968Natur.218..663S |doi = 10.1038/218663a0 |issue=5142|doi-access=free }}</ref>

Within a year others observed that the radio flux varied, and that light was [[Polarization (waves)|polarized]]. Peter Albert Strittmatter proposed the class of object in 1972 and added four objects. By 1976 there were 30 known objects.<ref name="stein1976">{{cite journal|last2=O'Dell|first2=S. L.|last3=Strittmatter|first3=P. A.|date=September 1976|title=The BL Lacertae Objects|url=http://james.as.arizona.edu/~psmith/Blazars/stein.pdf|journal=Annual Review of Astronomy and Astrophysics|volume=14|pages=173–195|bibcode=1976ARA&A..14..173S|doi=10.1146/annurev.aa.14.090176.001133|first1=W. A.|last1=Stein}}</ref>

In 2017, a very high energy neutrino was detected by the [[IceCube]] project apparently coming from BL Lac object [[TXS 0506+056]].<ref name="Overbye2018">{{ Cite news|url=https://www.nytimes.com/2018/07/12/science/space-neutrinos-blazar.html|title=It Came From a Black Hole, and Landed in Antarctica|last=Overbye|first=Dennis|work=NY Times|date=12 July 2018 |access-date=2018-07-16|language=en}}</ref>