C/1961 R1 (Humason)

Comet Humason, formally designated C/1961 R1, was a non-periodic comet discovered by Milton L. Humason on 1 September 1961. Its perihelion was well beyond the orbit of Mars, at 2.133 AU. The outbound orbital period is about 2,516 years.

Physical properties

It was a "giant" comet, much more active than a normal comet for its distance to the Sun, with an absolute magnitude of 1.35−3.5, and a nucleus diameter estimated at. It could have been up to a hundred times brighter than an average new comet. It had an unusually disrupted or "turbulent" appearance. It was also unusual in that the spectrum of its tail showed a strong predominance of the ion CO⁺, a result previously seen unambiguously only in C/1908 R1 (Morehouse).