1783 CE
John Michell Proposes 'Dark Stars'
John Michell suggests that stars with sufficient gravity could prevent light from escaping, anticipating the concept of black holes. #physics #astronomy
Chronological Storyline (45 Milestones)
1796 CE
Laplace Discusses Invisible Bodies
Pierre-Simon Laplace independently proposes 'invisible bodies' where escape velocity exceeds light speed, reinforcing the idea of dark stars. #physics #history
By James Posselwhite - www.britannica.com, Public domain, https://commons.wikimedia.org/w/index.php?curid=11128070
Nov 25, 1915 CE
Einstein's General Relativity Published
Albert Einstein presents the field equations of general relativity, providing the theoretical foundation for black holes. #physics #relativity
By Simulating eXtreme Spacetimes Lensing (SXS) - https://www.ligo.caltech.edu/video/ligo20160211v3 (video link); see also http://www.black-holes.org/gw150914, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=46994894
Jan 13, 1916 CE
Schwarzschild Solves Einstein's Equations
Karl Schwarzschild derives the first exact solution to Einstein's field equations, describing a non-rotating black hole. #physics #astronomy
1931 CE
Chandrasekhar Computes White Dwarf Limit
Subrahmanyan Chandrasekhar calculates the maximum mass of a stable white dwarf, implying that more massive stars must collapse into neutron stars or black holes. #astrophysics
1939 CE
Oppenheimer and Snyder Predict Black Holes
J. Robert Oppenheimer and Hartland Snyder show that massive stars can undergo gravitational collapse to form what would later be called black holes. #physics #history
1964 CE
Quasars Discovered as Distant Luminous Objects
The discovery of quasars (quasi-stellar radio sources) suggests extremely energetic phenomena, later attributed to supermassive black holes. #astronomy
By ESO/M. Kornmesser - http://www.eso.org/public/images/eso1122a/, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=15700804
1967 CE
Term 'Black Hole' Coined by John Wheeler
John Archibald Wheeler popularizes the term 'black hole' during a conference, replacing earlier names like 'frozen star'. #physics #history
By Event Horizon Telescope, uploader cropped and converted TIF to JPG - This media was produced by the European Southern Observatory (ESO), under the identifier eso1907a This tag does not indicate the copyright status of the attached work. A normal copyright tag is still required. See Commons:Licensing., CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=77925953
1967 CE
First Pulsar Discovered by Jocelyn Bell Burnell
The detection of pulsars (rapidly rotating neutron stars) confirms the existence of neutron stars and indirectly supports black hole theory. #astronomy
By NASA/CXC/SAO (X-Ray); NASA/JPL-Caltech (Infrared) - http://www.nasa.gov/sites/default/files/pia18848-wisefacepalm.jpg, Public domain, https://commons.wikimedia.org/w/index.php?curid=36363158
1969 CE
Penrose Process for Extracting Energy
Roger Penrose proposes that energy can be extracted from a rotating black hole via particle decay in the ergosphere. #physics
By L3erdnik - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=114665784
1970 CE
First Unambiguous Black Hole Candidate?
Cygnus X-1 becomes the first widely accepted black hole candidate. #astrophysics
1971 CE
First Black Hole Binary Identified
Cygnus X-1 is confirmed as a binary system containing a black hole and a supergiant star. #astronomy
1971 CE
Cygnus X-1 Identified as First Black Hole Candidate
Observations of the X-ray source Cygnus X-1 provide strong evidence for a stellar-mass black hole in a binary system. #astrophysics
By IAU and Sky & Telescope magazine (Roger Sinnott & Rick Fienberg) - [1], CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=15406373
1972 CE
Hawking Proposes Black Hole Area Theorem
Stephen Hawking proves that the event horizon area of a black hole never decreases, analogous to entropy in thermodynamics. #physics
By JRennocks - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=128242974
1972 CE
Superradiance Predicted
Yakov Zeldovich and others propose that waves can be amplified by scattering off a rotating black hole. #physics
1973 CE
Black Hole Thermodynamics Developed
Jacob Bekenstein suggests black holes have entropy proportional to event horizon area, leading to thermodynamic laws for black holes. #physics
1974 CE
Hawking Radiation Predicted
Stephen Hawking shows that black holes can emit thermal radiation due to quantum effects near the event horizon, leading to eventual evaporation. #physics #quantum
1975 CE
No Hair Theorem Established
The no-hair theorem states that black holes are completely described by only three parameters: mass, charge, and angular momentum. #physics
1980 CE
Inflationary Universe Predicts Primordial Black Holes
Inflation models suggest that density fluctuations could produce small black holes in the early universe. #cosmology
1985 CE
Roche Lobe Overflow in Black Hole X-Ray Binaries
Theory describes how mass transfer from a companion star powers black hole accretion. #astrophysics
By ESA, NASA, and Felix Mirabel (French Atomic Energy Commission and Institute for Astronomy and Space Physics/Conicet of Argentina) - https://science.nasa.gov/asset/hubble/artists-view-of-black-hole-and-companion-star-gro-j1655-40, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=78156
1990 CE
Hubble Space Telescope Launched
The Hubble Space Telescope provides high-resolution images of galactic centers, helping to identify supermassive black holes. #astronomy #space
By NASA - http://spaceflight.nasa.gov/gallery/images/shuttle/sts-125/html/s125e012050.html, Public domain, https://commons.wikimedia.org/w/index.php?curid=6833760
1992 CE
First Image of a Black Hole Accretion Disk?
The Hubble Space Telescope images the core of galaxy M87, revealing a jet from a supermassive black hole. #astronomy
1995 CE
Supermassive Black Hole in Milky Way Confirmed
Observation of star orbits near the Galactic Center provides strong evidence for a supermassive black hole, Sagittarius A*. #astrophysics
By EHT Collaboration - https://www.eso.org/public/images/eso2208-eht-mwa/ (image link), CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=117933557
1996 CE
Black Hole Uniqueness Theorems Advanced
Mathematicians and physicists prove that stationary black holes are fully characterized by mass, charge, and spin. #physics #math
1999 CE
Chandra X-ray Observatory Launched
NASA's Chandra X-ray Observatory enables detailed studies of black hole accretion disks and jets. #astronomy #nasa
By NASA/CXC/NGST - http://svs.gsfc.nasa.gov/cgi-bin/details.cgi?aid=11185 (image link), Public domain, https://commons.wikimedia.org/w/index.php?curid=38252467
2002 CE
Mass of Supermassive Black Hole in Milky Way Measured
Using stellar orbits, the mass of Sagittarius A* is determined to be about 4 million solar masses. #astrophysics
2002 CE
First Measurement of Black Hole Spin
Using X-ray observations, astronomers measure the spin of the black hole in the binary system GRS 1915+105. #astrophysics
By PopePompus - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=119336804
2003 CE
First Observation of Black Hole 'Shadow'?
VLBI observations of Sgr A* show structure consistent with a shadow, but resolution is insufficient for direct imaging. #astronomy
2006 CE
Fermi Gamma-ray Space Telescope Launched
Fermi detects gamma-ray emissions from black hole jets and microquasars. #astronomy #nasa
By NASA - https://science.nasa.gov/toolkits/spacecraft-icons (image link), Public domain, https://commons.wikimedia.org/w/index.php?curid=58291732
2008 CE
Event Horizon Telescope Project Begins
The Event Horizon Telescope (EHT) collaboration is formed to directly image black hole event horizons using very-long-baseline interferometry. #astronomy #collaboration
By D. Marrone/UofA - Event Horizon Telescope Collaboration, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=133002860
2010 CE
Discovery of Tidal Disruption Events
Stars torn apart by supermassive black holes are observed as bright flares. #astrophysics
By Danieljamesprice - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=151976689
Sep 14, 2015 CE
First Gravitational Wave Detection (GW150914)
LIGO detects gravitational waves from a binary black hole merger, confirming the existence of stellar-mass black hole pairs. #physics #astronomy
By B. P. Abbott et al. (LIGO Scientific Collaboration and Virgo Collaboration) — full list at the end of the article - http://physics.aps.org/featured-article-pdf/10.1103/PhysRevLett.116.061102 . See also the associated Jupyter notebook., CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=46987868
2017 CE
LIGO and Virgo Detect Third Black Hole Merger
The third detection (GW170104) further validates general relativity and black hole population models. #physics
By LIGO Scientific and Virgo Collaboration - https://arxiv.org/abs/1706.01812, GW170104: Observation of a 50-Solar-Mass Binary Black Hole Coalescence at Redshift 0.2, Phys. Rev. Lett. 118, 221101, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=63028580
Apr 10, 2019 CE
First Image of a Black Hole (M87*)
The Event Horizon Telescope releases the first direct image of a black hole's event horizon, located in galaxy M87. #astronomy #breakthrough
By en:NASA, en:STScI, en:WikiSky - http://wikisky.org/snapshot?img_size=&img_res=&ra=12.5138&de=12.3896&angle=0.0293&projection=tan&rotation=0.0&survey=astrophoto&img_id=905632&width=2160&height=2160&img_borders=&interpolation=bicubic&jpeg_quality=0.8, Public domain, https://commons.wikimedia.org/w/index.php?curid=7598267
Sep 1, 2019 CE
First Neutron Star-Black Hole Merger Detected
LIGO and Virgo detect gravitational waves from a neutron star merging with a black hole. #physics
Nov 1, 2019 CE
Nobel Prize in Physics for Black Hole Discoveries
Roger Penrose receives half the Nobel Prize for theoretical discovery of black hole formation; Andrea Ghez and Reinhard Genzel share the other half for supermassive black hole discovery. #physics #nobel
2021 CE
Polarized Light Image of M87* Black Hole
EHT reveals polarized light signatures around M87*, showing magnetic fields at the event horizon. #astronomy
2021 CE
EHT Observes Black Hole in Centaurus A
The Event Horizon Telescope images the jet base of the supermassive black hole in Centaurus A. #astronomy
By ESO/WFI (Optical); MPIfR/ESO/APEX/A.Weiss et al. (Submillimetre); NASA/CXC/CfA/R.Kraft et al. (X-ray) - http://www.eso.org/public/images/eso0903a/, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=5821706
May 12, 2022 CE
First Image of Sagittarius A*
The Event Horizon Telescope images the supermassive black hole at the center of the Milky Way, Sagittarius A*. #astronomy
Jul 1, 2022 CE
JWST Observes Active Galactic Nuclei
The James Webb Space Telescope reveals new details about black holes in the early universe. #astronomy #webb
By NASA - https://www.jwst.nasa.gov/content/webbLaunch/whereIsWebb.html, Public domain, https://commons.wikimedia.org/w/index.php?curid=114125719
Oct 1, 2022 CE
Nobel Prize for Black Hole Imaging Team?
No, but the team continues to refine techniques.
2023 CE
LIGO-Virgo-KAGRA O4 Observing Run
The fourth observing run includes KAGRA, detecting many black hole mergers and neutron star collisions. #physics
By Amber Stuver - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=46993713
2023 CE
Fast Radio Bursts from Black Hole?
Possible link between fast radio bursts and black hole activity is proposed. #astrophysics
By Psr1909 - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=44102265
2024 CE
LISA Pathfinder Predecessor for Gravitational Wave Observatory
The Laser Interferometer Space Antenna (LISA) mission continues development to detect low-frequency gravitational waves from supermassive black hole mergers. #physics #space
2024 CE
Dark Matter as Primordial Black Holes?
Ongoing research explores whether primordial black holes could constitute dark matter.
By European Space Agency - https://www.esa.int/Science_Exploration/Space_Science/Did_black_holes_form_immediately_after_the_Big_Bang https://open.esa.int/image-usage-creative-commons/, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=113427057