extrasolar comet
exocomet

Besides known comets within the Solar System, or known extrasolar comets, no interstellar comet, not gravitationally bound to a star, has been conclusively identified.

An exocomet, or extrasolar comet, is a comet outside the Solar System, including interstellar comets and comets that orbit stars other than the Sun.

In addition to these exoplanets, scientists have begun discovering vast clouds of extrasolar comets, including balls of ice and rock that may be pelting these far-off worlds.

The first exocomet system was discovered in 1987, and three more were spotted over the years.

The researchers discovered the six new exocomet systems using the 2.1-meter telescope of the McDonald Observatory in Texas.

The first exocomet system detected was around Beta Pictoris, a very young A-type main-sequence star, in 1987.

An interstellar comet is a comet (or exocomet) located in interstellar space, and not gravitationally bound to a star.

An exocomet, or extrasolar comet, is a comet outside the Solar System, including interstellar comets and comets that orbit stars other than the Sun.

Changes are observed in the absorption lines of the stellar spectrum: the occultation of the star by the gas cloud coming from the exocomet produces additional absorption features, like those observed in the ionized calcium lines.