| 161P/Hartley-IRAS | |
| Discoverer: | Malcolm Hartley IRAS |
| Discovery Date: | November 4, 1983 |
| Designations: | 1984 III; 2004 V2 |
| Epoch: | March 6, 2006 |
| Semimajor: | 7.734 AU |
| Perihelion: | 1.275 AU |
| Aphelion: | 14.19 AU |
| Eccentricity: | 0.8351 |
| Period: | 21.51 yr |
| Inclination: | 95.6899° |
| Last P: | June 20, 2005 |
| Next P: | 2026 Oct. 29 2026 Nov. 27 2026 December 18 |
161P/Hartley–IRAS is a periodic comet with an orbital period of 21 years. It fits the classical definition of a Halley-type comet with (20 years < period < 200 years).
This was one of six comets discovered by the infrared space telescope IRAS, in 1983.[1]