The C-12/C-13 abundance ratio in Comet Halley

Journal Article · Sat Apr 01 00:00:00 EST 1989 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/167312· OSTI ID:5813624

Wyckoff, S; Lindholm, E; Wehinger, P A; Peterson, B A; Zucconi, J M

The individual (C-13)N rotational lines in Comet Halley are resolved using high-resolution spectra of the CN B2Sigma(+)-X2Sigma(+) (0,0) band. The observe C-12/C-13 abundance ratio excludes a site of origin for the comet near Uranus and Neptune and suggests a condensation environment quite distinct from other solar system bodies. Two theories are presented for the origin of Comet Halley. One theory suggest that the comet originated 4.5 Gyr ago in an inner Oort cloud at a heliocentric distance greater than 100 AU where chemical fractionation led to the C-13 enrichment in the CN parent molecule prior to condensation of the comet nucleus. According to the other, more plausible theory, the comet nucleus condensed relatively recently from the interstellar medium which has become enriches in C-13 and was subsequently gravitationally captured by the solar system. 107 refs.

• Research Organization: Arizona State Univ., Tempe (USA); Mount Stromlo and Siding Spring Observatories, Canberra (Australia); Besancon, Observatoire (France)
• OSTI ID: 5813624
• Journal Information: Astrophys. J.; (United States), Vol. 339
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
HALLEY COMET
ORIGIN
ABUNDANCE
CARBON ISOTOPES
CHEMICAL COMPOSITION
GRAVITATIONAL INTERACTIONS
INTERSTELLAR SPACE
ISOTOPE RATIO
RESOLUTION
SOLAR SYSTEM
BASIC INTERACTIONS
COMETS
INTERACTIONS
ISOTOPES
SPACE
640107* - Astrophysics & Cosmology- Planetary Phenomena