Editing Chandra X-ray Observatory (section)

==Example discoveries==
[[File:STS-93 crew.jpg|thumb|Crew of STS-93 with a scale model]]
The data gathered by Chandra has greatly advanced the field of [[X-ray astronomy]]. Here are some examples of discoveries supported by observations from Chandra:
* The [[First light (astronomy)|first light]] image, of [[supernova remnant]] [[Cassiopeia A]], gave astronomers their first glimpse of the [[compact object]] at the center of the remnant, probably a neutron star or black hole.<ref>{{cite web |last=Hall |first=Alan |title=Chandra Sees Its 'First Light' |url=https://www.scientificamerican.com/article/chandra-sees-its-first-li/ |access-date=September 27, 2023 |website=Scientific American }}</ref><ref>{{cite journal |title=The Compact Central Object in Cassiopeia A: A Neutron Star with Hot Polar Caps or a Black Hole? |journal=[[The Astrophysical Journal]] |last1=Pavlov |first1=G. G. |last2=Zavlin |first2=V. E. |last3=Aschenbach |first3=B. |last4=Trumper |first4=J. |last5=Sanwal |first5=D. |volume=531 |issue=1 |pages=L53–L56 |date=2000 |arxiv=astro-ph/9912024 |doi=10.1086/312521 |pmid=10673413 |bibcode=2000ApJ...531L..53P |s2cid=16849221 }}</ref>
* In the [[Crab Nebula]], another supernova remnant, Chandra showed a never-before-seen ring around the central [[pulsar]] and jets that had only been partially seen by earlier telescopes.<ref>{{cite journal |title=Discovery of Spatial and Spectral Structure in the X-Ray Emission from the Crab Nebula |journal=[[The Astrophysical Journal]] |last1=Weisskopf |first1=M. C. |last2=Hester |first2=J. J. |last3=Tennant |first3=A. F. |last4=Elsner |first4=R. F. |last5=Schulz |first5=N. S. |last6=Marshall |first6=H. L. |last7=Karovska |first7=M. |last8=Nichols |first8=J. S. |last9=Swartz |first9=D. A. |last10=Kolodziejczak |first10=J. J. |last11=O'Dell |first11=S. L. |display-authors=9 |volume=536 |issue=2 |pages=L81–L84 |date=2000 |arxiv=astro-ph/0003216 |doi=10.1086/312733 |pmid=10859123 |bibcode=2000ApJ...536L..81W|s2cid=14879330 }}</ref>
* The first X-ray emission was seen from the [[supermassive black hole]], [[Sagittarius A*]], at the [[Galactic Center|center]] of the [[Milky Way]].<ref>{{cite journal |title=Rapid X-ray flaring from the direction of the supermassive black hole at the Galactic Centre |journal=[[Nature (journal)|Nature]] |first1=F. K. |last1=Baganoff |first2=M. W. |last2=Bautz |first3=W. N. |last3=Brandt |first4=G. |last4=Chartas |first5=E. D. |last5=Feigelson |first6=G. P. |last6=Garmire |first7=Y. |last7=Maeda |first8=M. |last8=Morris |first9=G. R. |last9=Ricker |first10=L. K. |last10=Townsley |first11=F. |last11=Walter |display-authors=9 |volume=413 |issue=6851 |pages=45–48 |date=2001 |arxiv=astro-ph/0109367 |doi=10.1038/35092510 |pmid=11544519 |bibcode=2001Natur.413...45B|s2cid=2298716 }}</ref>
* Chandra confirmed that X-rays in [[O-type stars]] are generated through plasma shocks embedded in their wind.<ref>{{cite journal |title=Chandra Discovers a Very High Density X-Ray Plasma on the O Star ζ Orionis |journal=[[The Astrophysical Journal]] |last1=Waldron |first1=Wayne L. |last2=Cassinelli |first2=Joseph P. |volume=548 |issue=1 |pages=L45-L48 |date=2001 |arxiv=astro-ph/0012190 |doi=10.1086/318926 |bibcode=2001ApJ...548L..45W }}</ref>
* Chandra found much more cool [[gas]] than expected spiraling into the center of the [[Andromeda Galaxy]].
* Pressure fronts were observed in detail for the first time in [[Abell 2142]], where [[galaxy cluster|clusters]] of galaxies are merging.
* The earliest images in X-rays of the [[shock wave]] of a [[supernova]] were taken of [[SN 1987A]].
* Chandra showed for the first time the shadow of a small [[galaxy]] as it is being cannibalized by a larger one, in an image of [[Perseus A]].
* A new type of black hole was discovered in galaxy [[Messier 82|M82]], mid-mass objects purported to be the missing link between [[Stellar black hole|stellar-sized black holes]] and [[super massive black holes]].<ref>{{cite journal |title=Hot Plasma and Black Hole Binaries in Starburst Galaxy M82 |journal=[[Science (journal)|Science]] |first1=R. E. |last1=Griffiths |first2=A. |last2=Ptak |first3=E. D. |last3=Feigelson |first4=G. |last4=Garmire |first5=L. |last5=Townsley |first6=W. N. |last6=Brandt |first7=R. |last7=Sambruna |first8=J. N. |last8=Bregman |volume=290 |issue=5495 |pages=1325–1328 |date=2000 |doi=10.1126/science.290.5495.1325 |pmid=11082054 |bibcode=2000Sci...290.1325G }}</ref>
* X-ray [[emission line]]s were associated for the first time with a [[gamma-ray burst]], [[Beethoven Burst]] GRB 991216.<ref>{{cite journal |title=Observation of X-ray lines from a gamma-ray burst (GRB991216): evidence of moving ejecta from the progenitor |journal=[[Science (journal)|Science]] |first1=L. |last1=Piro |first2=G. |last2=Garmire |first3=M. |last3=Garcia |first4=G. |last4=Stratta |first5=E. |last5=Costa |first6=M. |last6=Feroci |first7=P. |last7=Meszaros |first8=M. |last8=Vietri |first9=H. |last9=Bradt |first10=D. |last10=Frail |first11=F. |last11=Frontera |first12=J. |last12=Halpern |first13=J. |last13=Heise |first14=K. |last14=Hurley |first15=N. |last15=Kawai |first16=R. M. |last16=Kippen |first17=F. |last17=Marshall |first18=T. |last18=Murakami |first19=V. V. |last19=Sokolov |first20=T. |last20=Takeshima |first21=A. |last21=Yoshida |display-authors=9 |volume=290 |issue=5493 |pages=955–958 |date=2000 |arxiv=astro-ph/0011337 |doi=10.1126/science.290.5493.955 |pmid=11062121 |bibcode=2000Sci...290..955P|s2cid=35190896 }}</ref>
* High school students, using Chandra data, [[CXOU J061705.3+222127|discovered]] a neutron star in supernova remnant [[IC 443]].<ref>{{cite press release |url=http://quest.nasa.gov/dso/news/press_release/12-11-00.txt |title=Students Using NASA and NSF Data Make Stellar Discovery; Win Science Team Competition |publisher=NASA |id=Release 00-195 |date=December 12, 2000 |archive-url=https://web.archive.org/web/20130510130847/http://quest.nasa.gov/dso/news/press_release/12-11-00.txt |archive-date=May 10, 2013 }}</ref>
* Observations by Chandra and [[BeppoSAX]] suggest that gamma-ray bursts occur in [[star-forming region]]s.
* Chandra data suggested that [[RX J1856.5-3754]] and [[3C58]], previously thought to be pulsars, might be even denser objects: [[quark star]]s. These results are still debated.
* Sound waves from violent activity around a [[super massive black hole]] were observed in the [[Perseus Cluster]] (2003).
* [[File:Chandra X-ray Observatory image of the brown dwarf TWA 5B.jpg|thumb|CXO image of the brown dwarf TWA 5B]]TWA 5B, a [[brown dwarf]], was seen orbiting a [[binary star|binary]] system of Sun-like [[star]]s.
* Nearly all stars on the [[main sequence]] are X-ray emitters.<ref>Schmitt & Liefke, 2004</ref>
* The X-ray shadow of [[Titan (moon)|Titan]] was seen when it [[Astronomical transit|transited]] the Crab Nebula.
* X-ray emissions from materials falling from a [[protoplanetary disc]] into a star.<ref>{{cite journal |title=An X-ray outburst from the rapidly accreting young star that illuminates McNeil's nebula |journal=[[Nature (journal)|Nature]] |first1=J. H. |last1=Kastner |first2=M. |last2=Richmond |first3=N. |last3=Grosso |first4=D. A. |last4=Weintraub |first5=T. |last5=Simon |first6=A. |last6=Frank |first7=K. |last7=Hamaguchi |first8=H. |last8=Ozawa |first9=A. |last9=Henden |volume=430 |issue=6998 |pages=429–431 |date=2004 |arxiv=astro-ph/0408332 |doi=10.1038/nature02747 |pmid=15269761 |bibcode=2004Natur.430..429K|s2cid=1186552 }}</ref>
* [[Hubble constant]] measured to be 76.9&nbsp;km/s/[[Parsec|Mpc]] using [[Sunyaev-Zel'dovich effect]].<ref>{{cite journal |title=Determination of the Cosmic Distance Scale from Sunyaev-Zel'dovich Effect and Chandra X-Ray Measurements of High-Redshift Galaxy Clusters |last1=Bonamente |first1=Massimiliano |last2=Joy |first2=Marshall |last3=LaRoque |first3=Samuel |last4=Carlstrom |first4=John |last5=Reese |first5=Erik |last6=Dawson |first6=Kyle |date=August 10, 2006 |journal=The Astrophysical Journal |volume=647 |issue=1 |pages=25–54 |doi=10.1086/505291 |arxiv=astro-ph/0512349 |bibcode=2006ApJ...647...25B |s2cid=15723115 }}</ref>
* 2006 Chandra found strong evidence that dark matter exists by observing super cluster collision.<ref>{{cite journal |title=A Direct Empirical Proof of the Existence of Dark Matter |last1=Clowe |first1=Douglas |last2=Bradač |first2=Maruša |last3=Gonzalez |first3=Anthony |last4=Markevitch |first4=Maxim |last5=Randall |first5=Scott |last6=Jones |first6=Christine |last7=Zaritsky |first7=Dennis |date=August 30, 2006 |journal=The Astrophysical Journal |volume=648 |issue=2 |pages=L109–L113 |doi=10.1086/508162 |arxiv=astro-ph/0608407 |bibcode=2006ApJ...648L.109C |doi-access=free }}</ref>
* 2006 X-ray emitting loops, rings and filaments discovered around a [[super massive black hole]] within [[Messier 87]] imply the presence of pressure waves, shock waves and sound waves. The evolution of [[Messier 87]] may have been dramatically affected.<ref>{{cite press release |last1=Roy |first1=Steve |last2=Watzke |first2=Megan |url=http://chandra.harvard.edu/press/06_releases/press_100506.html |title=Chandra Reviews Black Hole Musical: Epic But Off-Key |publisher=Center for Astrophysics {{!}} Harvard & Smithsonian |date=October 2006}}</ref>
* Observations of the [[Bullet cluster]] put limits on the cross-section of the self-interaction of [[dark matter]].<ref>{{cite conference |title=Recent and Future Observations in the X-ray and Gamma-ray Bands: Chandra, Suzaku, GLAST, and NuSTAR |conference=Astrophysical Sources of High Energy Particles and Radiation. June 20–24, 2005. Torun, Poland. |series=AIP Conference Proceedings |first=Greg |last=Madejski |volume=801 |page=21 |date=2005 |doi=10.1063/1.2141828 |arxiv=astro-ph/0512012 }}</ref>
* "The Hand of God" photograph of [[PSR B1509-58]].
* Jupiter's x-rays coming from poles, not auroral ring.<ref>{{cite news |url=https://science.nasa.gov/science-news/science-at-nasa/2002/07mar_jupiterpuzzle/ |title=Puzzling X-rays from Jupiter |publisher=NASA |date=March 7, 2002 |access-date=July 12, 2022 }}</ref>
* A large halo of hot gas was found surrounding the Milky Way.<ref>{{cite web |first1=J. D. |last1=Harrington |first2=Janet |last2=Anderson |first3=Peter |last3=Edmonds |date=September 24, 2012 |url=http://www.nasa.gov/mission_pages/chandra/news/H-12-331.html |title=NASA's Chandra Shows Milky Way is Surrounded by Halo of Hot Gas |publisher=NASA }}</ref>
* Extremely dense and luminous dwarf galaxy [[M60-UCD1]] observed.<ref>{{cite web |url=http://www.nasa.gov/mission_pages/chandra/multimedia/m60-dense-galaxy.html |title=M60-UCD1: An Ultra-Compact Dwarf Galaxy |publisher=NASA |date=September 24, 2013}}</ref>
* On January 5, 2015, NASA reported that CXO observed an [[X-ray]] flare 400 times brighter than usual, a record-breaker, from [[Sagittarius A*]], the [[supermassive black hole]] in the center of the [[Milky Way|Milky Way galaxy]]. The unusual event may have been caused by the breaking apart of an [[asteroid]] falling into the black hole or by the entanglement of [[magnetic field lines]] within gas flowing into Sagittarius A*, according to astronomers.<ref name="NASA-20150105">{{cite web |last1=Chou |first1=Felicia |last2=Anderson |first2=Janet |last3=Watzke |first3=Megan |title=RELEASE 15-001 - NASA's Chandra Detects Record-Breaking Outburst from Milky Way's Black Hole |url=http://www.nasa.gov/press/2015/january/nasa-s-chandra-detects-record-breaking-outburst-from-milky-way-s-black-hole/ |date=January 5, 2015 |work=[[NASA]] |access-date=January 6, 2015}}</ref>
* In September 2016, it was announced that Chandra had detected X-ray emissions from [[Pluto]], the first detection of X-rays from a [[Kuiper belt]] object. Chandra had made the observations in 2014 and 2015, supporting the ''[[New Horizons]]'' spacecraft for its July 2015 encounter.<ref>{{cite web |url=http://www.jhuapl.edu/newscenter/pressreleases/2016/160914.asp |title=X-Ray Detection Sheds New Light on Pluto |publisher=[[Applied Physics Laboratory]] |date=September 14, 2016 |archive-url=https://web.archive.org/web/20161017110547/http://jhuapl.edu/newscenter/pressreleases/2016/160914.asp |archive-date=October 17, 2016 }}</ref>
* In September 2020, Chandra reportedly may have made an observation of an [[exoplanet]] in the [[Whirlpool Galaxy]], which would be the first planet discovered beyond the Milky Way.<ref>{{Cite news |first=Paul |last=Rincon |date=October 25, 2021 |title=Signs of first planet found outside our galaxy |work=BBC News |url=https://www.bbc.com/news/science-environment-59044650 |archive-url=https://web.archive.org/web/20211025214850/https://www.bbc.com/news/science-environment-59044650 |archive-date=October 25, 2021 |url-status=live }}</ref><ref>{{cite news |last=Crane |first=Leah |title=Astronomers May Have Found the First Planet in Another Galaxy |url=https://www.newscientist.com/article/2255431-astronomers-may-have-found-the-first-planet-in-another-galaxy/ |date=September 23, 2020 |work=[[New Scientist]] |access-date=September 25, 2020 }}</ref><ref>{{cite arXiv |last=Di Stefano |first=R. |display-authors=et al. |title=M51-ULS-1b: The First Candidate for a Planet in an External Galaxy |eprint=2009.08987 |date=September 18, 2020 |class=astro-ph.HE }}</ref>
* In April 2021, NASA announced findings from the observatory in a tweet saying "Uranus gives off X-rays, astronomers find". The discovery would have "intriguing implications for understanding Uranus" if it is confirmed that the X-rays originate from the planet and are not emitted by the Sun.<ref>{{cite web |last=Mohon |first=Lee |date=March 30, 2021 |title=First X-rays from Uranus Discovered |url=http://www.nasa.gov/mission_pages/chandra/images/first-x-rays-from-uranus-discovered.html |archive-date=July 25, 2022 |archive-url=https://web.archive.org/web/20220725172011/https://www.nasa.gov/mission_pages/chandra/images/first-x-rays-from-uranus-discovered.html |publisher=NASA }}</ref>