| C/1961 R1 (Humason) | |
| Discoverer: | Milton L. Humason |
| Discovery Date: | 1 September 1961 |
| Designations: | 1961e 1962 VIII |
| Epoch: | 12 May 1963 (JD 2438161.5) |
| Observation Arc: | 1,517 days (4.15 years) |
| Obs: | 80 |
| Perihelion: | 2.133 AU |
| Aphelion: | 408.71 AU |
| Semimajor: | 205.42 AU |
| Eccentricity: | 0.98961 |
| Period: | 2,883 years (inbound) 2,516 years (outbound) |
| Inclination: | 153.278° |
| Asc Node: | 155.439° |
| Arg Peri: | 233.562° |
| Tjup: | –1.588 |
| Earth Moid: | 1.2247 AU |
| Jupiter Moid: | 1.0725 AU |
| M1: | 1.35–3.5 |
| M2: | 10.1 |
| Last P: | 10 December 1962 |
Comet Humason, formally designated C/1961 R1 (a.k.a. 1962 VIII and 1961e), 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.
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).