266P/Christensen

266P/Christensen
Discovery
Discovered byEric J. Christensen
Discovery siteCatalina Sky Survey
Discovery date27 October 2006
Designations
P/2006 U5
P/2012 P1
Christensen 12
Orbital characteristics
Epoch26 December 2026 (JD 2461400.5)
Observation arc19.95 years
Number of
observations		913
Aphelion4.733 AU
Perihelion2.324 AU
Semi-major axis3.529 AU
Eccentricity0.34133
Orbital period6.628 years
Inclination3.429°
4.941°
Argument of
periapsis		97.951°
Mean anomaly2.763°
Last perihelion19 April 2020
Next perihelion7 December 2026
TJupiter3.020
Earth MOID1.351 AU
Jupiter MOID0.526 AU
Physical characteristics
Mean radius
1.66 km (1.03 mi)
Comet total
magnitude (M1)		11.0
Comet nuclear
magnitude (M2)		15.9

266P/Christensen is a Encke-type comet with a 6.63-year orbit around the Sun. It will next come to perihelion in December 2026. It had been suggested as the possible source of the 1977 "Wow! Signal", however this was later disproven by a follow-up study in 2020, where it was found out to be likely a maser-like flare from small hydrogen clouds in interstellar space instead. It reaches perihelion on 7 December 2026 and gets slightly brighter when it passes 1.4 AU from Earth on 13 January 2027.

Physical characteristics

Observations conducted by the Sloan Digital Sky Survey (SDSS) in 2012 revealed that the nucleus of 266P has an upper limit no greater than 1.66 km (1.03 mi) in radius.

Notes

  1. ↑ Observation arc from the Minor Planet Center database covering dates from 27 October 2006 until 8 October 2026.

References

  1. ↑ E. J. Christensen; G. Hug; G. Sostero; et al. (29 October 2006). D. W. Green (ed.). "Comet C/2006 U5 (Christensen)". IAU Circular (8768): 1. Bibcode:2006IAUC.8768....1C.
  2. ↑ "Periodic Comet Names and Designations". Planetary Data System: Small Body Node. NASA. Retrieved 22 September 2026.
  3. 1 2 "266P/Christensen – JPL Small-Body Database Lookup". ssd.jpl.nasa.gov. Jet Propulsion Laboratory. Retrieved 10 November 2025.
  4. ↑ "266P/Christensen Orbit". Minor Planet Center. Retrieved 8 June 2017.
  5. 1 2 M. Solontoi; Ž. Ivezíc; M. Juríc (2012). "Ensemble properties of comets in the Sloan Digital Sky Survey". Icarus. 218 (1): 571–584. arXiv:1202.3999. Bibcode:2012Icar..218..571S. doi:10.1016/j.icarus.2011.10.008.
  6. ↑ A. Paris; E. Davies (2015). "Hydrogen Clouds from Comets 266/P Christensen and P/2008 Y2 (Gibbs) are Candidates for the Source of the 1977 "WOW" Signal" (PDF). Washington Academy of Sciences. 101 (4): 25–32. arXiv:1706.04642. Bibcode:2017arXiv170604642P. JSTOR jwashacadscie.101.4.25.
  7. ↑ A. Méndez; K. O. Ceballos; J. I. Zuluaga (2020). "Arecibo Wow! I: An Astrophysical Explanation for the Wow! Signal". arXiv:2408.08513 [astro-ph.HE].