| Sigma Hydrids | |
| Parent: | Unknown C/2023 P1 (Nishimura)? |
| Constellation: | Hydra |
| Month: | November 22 to January 4 |
| Peak: | December 7 |
| Velocity: | 58.8 |
| Zhr: | 3-7 |
Sigma Hydrids are a faint, minor (Class II) meteor shower that peak around 7 December. The ZHR is 3-7 and population index is 3. They are active from November 22 to January 4.
Sigma hydrids were discovered by Richard E. McCrosky and Annette Posen.[1]
Long-period comet C/2023 P1 (Nishimura) has been suggested to be the parent body of the meteor shower and came to perihelion (closest approach to the Sun) in September 2023. There is a chance of increased activity during the 2023 meteor shower if Earth passes through older meteoroid streams (such as 1591) that have had time to spread out over the comets orbit.[2]