Interstellar comet discovered?
An amateur astronomer has discovered what appears right now to be an interstellar comet making its approach into the solar system.
[I]mages show that the incoming object sports a faint but distinct coma and the barest hint of a tail — something ‘Oumuamua lacked — and thus appears to be a comet. Astronomers are no doubt eager to get spectra of the new find to determine what compounds might be escaping from its surface.
Based on current observations, C/2019 Q4’s eccentricity is about 3.2 — definitely hyperbolic. Objects on hyperbolic orbits are unbound to the Sun. They’re most likely to hail from beyond the solar system, flying in from great distances to pay our neighborhood a brief visit before heading off for parts unknown.
If this result holds up, astronomers have an unprecedented opportunity to study a potentially interstellar object in great detail over a long span of time. Based on the comet’s current magnitude (~18) and distance from the Sun (2.7 a.u.), it appears to be a fairly large object — perhaps 10 km or more across, depending on the reflectivity of its surface.
There remains a great deal of uncertainty about comet’s path, which will be better resolved with time and better data.
If it is a comet from beyond the solar system, it will be a spectacular goldmine for scientists, because its coma and tail will allow them to gather a great deal of information about its make-up, far more than they were able to gather about Oumuamua.
An amateur astronomer has discovered what appears right now to be an interstellar comet making its approach into the solar system.
[I]mages show that the incoming object sports a faint but distinct coma and the barest hint of a tail — something ‘Oumuamua lacked — and thus appears to be a comet. Astronomers are no doubt eager to get spectra of the new find to determine what compounds might be escaping from its surface.
Based on current observations, C/2019 Q4’s eccentricity is about 3.2 — definitely hyperbolic. Objects on hyperbolic orbits are unbound to the Sun. They’re most likely to hail from beyond the solar system, flying in from great distances to pay our neighborhood a brief visit before heading off for parts unknown.
If this result holds up, astronomers have an unprecedented opportunity to study a potentially interstellar object in great detail over a long span of time. Based on the comet’s current magnitude (~18) and distance from the Sun (2.7 a.u.), it appears to be a fairly large object — perhaps 10 km or more across, depending on the reflectivity of its surface.
There remains a great deal of uncertainty about comet’s path, which will be better resolved with time and better data.
If it is a comet from beyond the solar system, it will be a spectacular goldmine for scientists, because its coma and tail will allow them to gather a great deal of information about its make-up, far more than they were able to gather about Oumuamua.




