| C/2009 F6 (Yi–SWAN) | |
| Discoverer: | Dae-am Yi, SWAN instrument on SOHO spacecraft |
| Discovery Date: | March 26, 2009 |
| Epoch: | 2009-May-22 |
| Semimajor: | 453 AU |
| Perihelion: | 1.274072 AU |
| Aphelion: | 904 AU |
| Eccentricity: | 0.997031 |
| Period: | ~9,600 yr[1] |
| Inclination: | 85.7668 |
| Last P: | April 7, 2009 |
Comet C/2009 F6 (Yi–SWAN) is a non-periodic comet which appeared in March 2009.
March 26, 2009—it was discovered by Korean Dae-am Yi using a simple hand-held Canon 5D camera and 90-mm lens valued at US$249. According to legend, it is the first comet discovered by a Korean in the modern age.[2] April 4, 2009—Rob Matson reported he discovered it in the SWAN instrument photographs on the SOHO (Solar and Heliospheric Observatory) spacecraft website; the estimated cost is believed to exceed US$160,000,000,000.[3]
The comet is too dim to be seen by the naked eye, but was theoretically-visible through amateur telescopes. It is hard to watch because it is small with a tiny tail in the visible-light spectrum. It reached a peak magnitude around +8.5 in April into May, and passed 1.5 degrees south of the Double cluster in Perseus on April 23.[3]