The sunward spike of Halley’s comet

Autor: G. Emerson, R. E. Schmidt, Zdenek Sekanina, E. F. Helin, S. Larson
Rok vydání: 1988
Předmět:
Zdroj: Exploration of Halley’s Comet ISBN: 9783642829734
DOI: 10.1007/978-3-642-82971-0_116
Popis: On wide-field photographs from late April till early June 1986, comet Halley is seen to display a spike-like extension in the general direction of the Sun, projecting to distances of about 700,000 km from the nucleus. The spike was composed of dust and its enormous sunward extent (compared to other dust features) suggests an anomalously high ratio of particle ejection velocity to solar radiation pressure. The grains are either dielectric or slightly absorbing, ≪0.1 µm in size, and undetected optically from Earth except when it is located in or very near a plane of their concentration. The only plane to which these grains ejected from Halley’s wobbling nucleus can possibly be confined for long is the plane normal to the comet’s angular momentum vector. This concept is applied to interpret the spike observations.
Databáze: OpenAIRE