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The term astrophysical neutrino naturally refers to a neutrino other than those from Earth (from radioactive decay, human activities such as nuclear reactors, and reactions on Earth from cosmic rays), and typically also is meant to exclude the two well-known sources that produce the majority of neutrinos reaching Earth: the cosmic neutrino background, and solar neutrinos. Both these excluded populations have limited kinetic energy, and the term astrophysical neutrino often is used to mean higher energy than solar (though this could conceivably exclude some neutrinos from distant sources that happen to have lower energy). To further-study the source that produced some particular astrophysical neutrino, you must detect the direction it came from: knowing that direction, you can view the same source at various EMR bands (multi-messenger astronomy). The term astrophysical neutrino is sometimes meant to imply the neutrino's trajectory has been determined or partially determined. Astrophysical neutrino research progress has been limited in the past because handling their rarity and handling their high energy, as well as determining their trajectory, all demand large, expensive detectors.
Astrophysical neutrinos are presumed to be generated by high-energy astronomical events. An example is detected neutrinos from SN 1987A.
Some other neutrino terms regarding their sources that are also generally associated with more specific energy intervals: extragalactic neutrino, cosmological neutrino, GZK neutrino (aka cosmogenic neutrino), the latter presumed to be a product of the GZK effect.