Editing Astronomical radio source (section)

==Sources: Galactic==
=== The Galactic Center ===
The [[Galactic Center|center of the Milky Way]] was the first radio source to be detected. It contains a number of radio sources, including [[Sagittarius A]], the compact region around the [[supermassive black hole]], [[Sagittarius A*]], as well as the black hole itself. When flaring, the [[accretion disk]] around the supermassive black hole lights up, detectable in radio waves. 

In the 2000s, three Galactic Center Radio Transients (GCRTs) were detected: GCRT J1746–2757, GCRT J1745–3009, and
GCRT J1742–3001.<ref name=ASKAP-J17/> In addition, ASKAP J173608.2-321635, which was detected six times in 2020, may be a fourth GCRT.<ref name="SA-20210907">{{cite news |last=Starr |first=Michelle |title=Something Mysterious Near The Galactic Center Is Flashing Radio Signals |url=https://www.sciencealert.com/something-near-the-galactic-centre-is-flashing-radio-signals-and-we-don-t-know-what-it-is |date=7 September 2021 |work=[[ScienceAlert]] |accessdate=September 7, 2021 |archive-date=7 September 2021 |archive-url=https://web.archive.org/web/20210907070245/https://www.sciencealert.com/something-near-the-galactic-centre-is-flashing-radio-signals-and-we-don-t-know-what-it-is |url-status=live }}</ref><ref name=ASKAP-J17/>

;Region around the Galactic Center
In 2021, astronomers reported the detection of peculiar, highly [[Circular polarization|circularly]] [[Polarization in astronomy|polarized]] intermittent radio waves from near the Galactic Center whose [[Andy's object|unidentified source]] could represent a new class of astronomical objects with a GCRT so far not "fully explain[ing] the observations".<ref>{{cite news |last1=Hunt |first1=Katie |title=Strange radio waves from the heart of the Milky Way stump scientists |url=https://edition.cnn.com/2021/10/12/world/strange-radio-waves-milky-way-scn/index.html |access-date=18 October 2021 |work=CNN |archive-date=18 October 2021 |archive-url=https://web.archive.org/web/20211018084141/https://edition.cnn.com/2021/10/12/world/strange-radio-waves-milky-way-scn/index.html |url-status=live }}</ref><ref><!--Explanatory report by some of the paper's authors: -->{{cite web |last1=Wang |first1=Ziteng |last2=Kaplan |first2=David |last3=Murphy |first3=Tara |last4=Conversation |first4=The |title=We found a mysterious flashing radio signal from near the centre of the galaxy |url=https://phys.org/news/2021-10-mysterious-radio-centre-galaxy.html |access-date=18 October 2021 |work=phys.org |language=en |archive-date=18 October 2021 |archive-url=https://web.archive.org/web/20211018084142/https://phys.org/news/2021-10-mysterious-radio-centre-galaxy.html |url-status=live }}</ref><ref name=ASKAP-J17>{{cite journal |last1=Wang |first1=Ziteng |last2=Kaplan |first2=David L. |last3=Murphy |first3=Tara |last4=Lenc |first4=Emil |last5=Dai |first5=Shi |last6=Barr |first6=Ewan |last7=Dobie |first7=Dougal |last8=Gaensler |first8=B. M. |last9=Heald |first9=George |last10=Leung |first10=James K. |last11=O’Brien |first11=Andrew |last12=Pintaldi |first12=Sergio |last13=Pritchard |first13=Joshua |last14=Rea |first14=Nanda |last15=Sivakoff |first15=Gregory R. |last16=Stappers |first16=B. W. |last17=Stewart |first17=Adam |last18=Tremou |first18=E. |last19=Wang |first19=Yuanming |last20=Woudt |first20=Patrick A. |last21=Zic |first21=Andrew |title=Discovery of ASKAP J173608.2–321635 as a Highly Polarized Transient Point Source with the Australian SKA Pathfinder |journal=The Astrophysical Journal |date=1 October 2021 |volume=920 |issue=1 |pages=45 |doi=10.3847/1538-4357/ac2360 |language=en |issn=0004-637X |arxiv=2109.00652|bibcode=2021ApJ...920...45W |s2cid=237386202 |doi-access=free }}</ref>

===Supernova remnants===
[[Supernova remnant]]s often show diffuse radio emission. Examples include [[Cassiopeia A]], the brightest extrasolar radio source in the sky, and the [[Crab Nebula]].

===Neutron stars===

====Pulsars====
[[Image:Pulsar schematic.svg|thumb|right|Schematic view of a pulsar. The sphere in the middle represents the neutron star, the curves indicate the magnetic field lines, the protruding cones represent the emission beams and the green line represents the axis on which the star rotates.]]
Supernovae sometimes leave behind dense spinning [[neutron stars]] called [[pulsar]]s. They emit jets of charged particles which emit [[synchrotron radiation]] in the radio spectrum. Examples include the [[Crab Pulsar]], the first pulsar to be discovered. Pulsars and [[quasar]]s (dense central cores of extremely distant galaxies) were both discovered by radio astronomers. In 2003 astronomers using the [[Parkes Observatory|Parkes]] [[radio telescope]] discovered two pulsars orbiting each other, the first such system known.

====Rotating Radio Transient (RRAT) Sources ====
[[Rotating radio transient]]s (RRATs) are a type of neutron stars discovered in 2006 by a team led by [[Maura McLaughlin]] from the [[Jodrell Bank Observatory]] at the [[University of Manchester]] in the UK. RRATs are believed to produce radio emissions which are very difficult to locate, because of their transient nature.<ref>{{cite web |url=http://www.sciam.com/article.cfm?id=new-kind-of-star-found |title=New Kind of Star Found |author=David Biello |publisher=[[Scientific American]] |date=2006-02-16 |access-date=2010-06-23 |archive-date=2007-11-19 |archive-url=https://web.archive.org/web/20071119130837/http://www.sciam.com/article.cfm?id=new-kind-of-star-found |url-status=live }}</ref> Early efforts have been able to detect radio emissions (sometimes called '''RRAT flashes''')<ref>{{cite web |url=http://physicsworld.com/cws/article/news/24227/1/0602092 |title=RRAT flash |publisher=Physics World |author=Jodrell Bank Observatory |access-date=2010-06-23 |archive-date=2011-05-19 |archive-url=https://web.archive.org/web/20110519201228/http://physicsworld.com/cws/article/news/24227/1/0602092 |url-status=live }}</ref> for less than one second a day, and, like with other single-burst signals, one must take great care to distinguish them from terrestrial radio interference. Distributing computing and the Astropulse algorithm may thus lend itself to further detection of RRATs.

===Star forming regions===
Short [[radio waves]] are emitted from complex [[molecules]] in dense clouds of [[gas]] where [[star]]s are giving birth.

[[Spiral galaxy|Spiral galaxies]] contain clouds of [[neutral hydrogen]] and [[carbon monoxide]] which emit radio waves. The radio frequencies of these two molecules were used to map a large portion of the Milky Way galaxy.<ref>{{cite book|last=Gonzalez|first=Guillermo|author2=Wesley Richards|title=The Privileged Planet|publisher=[[Regnery Publishing]]|year=2004|isbn=0-89526-065-4|url=https://books.google.com/books?id=KFdu4CyQ1k0C|access-date=2008-04-02|page=382|archive-date=2021-04-27|archive-url=https://web.archive.org/web/20210427160442/https://books.google.com/books?id=KFdu4CyQ1k0C|url-status=live}}</ref>