Multi-messenger astronomy
Multi-messenger astronomy is astronomy based on the coordinated observation and interpretation of signals carried by disparate "messengers": electromagnetic radiation, gravitational waves, neutrinos, and cosmic rays. They are created by different astrophysical processes, and thus reveal different information about their sources.
The main multi-messenger sources outside the heliosphere are expected to be compact binary pairs (black holes and neutron stars), supernovae, irregular neutron stars, gamma-ray bursts, active galactic nuclei, and relativistic jets. The table below lists several types of events and expected messengers.
Detection from one messenger and non-detection from a different messenger can also be informative.
| Event type | Electromagnetic | Cosmic rays | Gravitational waves | Neutrinos | Example |
|---|---|---|---|---|---|
| Solar flare | yes | yes | - | - | SOL1942-02-28 |
| Supernova | yes | - | predicted | yes | SN 1987A |
| Neutron star merger | yes | - | yes | predicted | GW170817 |
| Blazar | yes | possible | - | yes | TXS 0506+056 (IceCube) |
| Active galactic nucleus | yes | possible | yes | Messier 77 (IceCube) | |
| Tidal disruption event | yes | possible | possible | yes | AT2019dsg (IceCube)
AT2019fdr (IceCube) |