Multi-messenger astronomy

Multi-messenger astronomy studies cosmic sources by combining information carried by different signals, including electromagnetic radiation, gravitational waves, neutrinos, and cosmic rays.

Gravitational-wave astronomy: Astronomy that detects gravitational waves to study their astrophysical sources. Gravitational waves provide a messenger that can escape dense matter and reveal the motion of massive objects.
GW170817: A gravitational-wave event detected in 2017 from the merger of two neutron stars. Its gravitational waves, gamma rays, and afterglow established a landmark multi-messenger observation.
Kilonova: A transient glow powered by radioactive decay in material ejected by merging neutron stars. Its light reveals heavy-element production in merger ejecta detected through gravitational waves.
LIGO: A laser interferometer observatory that detects gravitational waves in the United States. Its detections trigger searches for electromagnetic and neutrino counterparts.
Astrophysical distance ladder: A collection of methods for measuring distances to astronomical objects across increasing scales. Standard-siren distances from gravitational waves add a route independent of the traditional ladder.
Neutrino astronomy: Astronomy that uses neutrinos to investigate cosmic sources and processes. Neutrinos can emerge from environments opaque to light, adding evidence about energetic particle production.
SN 1987A: A supernova in the Large Magellanic Cloud first observed in 1987. Neutrinos detected alongside its light provided an early, direct view of a stellar core collapse.
R-process nucleosynthesis: The rapid neutron-capture process that creates many heavy atomic nuclei. Spectra of merger afterglows can test whether neutron-star collisions produce these elements.
Virgo interferometer: A European laser interferometer observatory for detecting gravitational waves. Its participation helps localize gravitational-wave sources for telescope follow-up.
Standard siren: A gravitational-wave source whose signal yields a distance estimate without a calibrated luminosity. Matching a siren to an electromagnetic host can constrain cosmic expansion.

Linked from 19 pages