40P/Väisälä
Sign in to save40P/Väisälä is a periodic comet that was discovered on February 8, 1939. Its orbit was determined on April 26, 1939. In 1994, the diameter of its nucleus was found to be , similar in size to that of Comet Encke. It came to perihelion on November 12, 2025.
Key facts
- Comet.name
- 40P/Väisälä
- Comet.image
- 40P 2026-01-20 image ZTF-sso-1371-zr-size-7.6arcmin.png
- Comet.caption
- Comet Väisälä 1 imaged on 20 January, 2026, by ZTF
- Comet.discoverer
- Yrjö Väisälä
- Comet.discovery_site
- University of Turku, Finland
- Comet.discovery_date
- February 8, 1939
- Comet.mpc_name
- P/1939 CBP/1949 Y1
- Comet.epoch
- May 5, 2025 (JD 2460800.5)
- Comet.observation_arc
- 86.16 years
- Comet.earliest_precovery_date
- January 18, 1939
- Comet.obs
- 1,243
- Comet.semimajor
- 4.951 AU
- Comet.perihelion
- 1.824 AU
- Comet.aphelion
- 8.079 AU
- Comet.eccentricity
- 0.63169
- Comet.period
- 11.018 years
- Comet.inclination
- 11.639°
- Comet.asc_node
- 128.90°
via Wikipedia infobox
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Encyclopedic overview
5 sectionsContents
- Discovery
- Outburst
- Orbit
- References
- External links
40P/Väisälä is a periodic comet that was discovered on February 8, 1939. Its orbit was determined on April 26, 1939. In 1994, the diameter of its nucleus was found to be , similar in size to that of Comet Encke. It came to perihelion on November 12, 2025.
== Discovery == Comet Väisälä was discovered accidentally on photographs exposed for minor planets. Originally, it was given the asteroid designation 1939 CB. However, additional findings revealed that the object was of cometary nature. The visual magnitude of Väisälä at the time of its discovery was 15. The orbital characteristics of the new comet at the time of its discovery were "a period of about 10 years, a perihelion date of April 26, 1939, and a perihelion distance of ."
Excerpted from Wikipedia’s “40P/Väisälä” article, available under the CC BY-SA 4.0 licence.