Comets and asteroids
View Comet 4P/Faye as it passes slightly to the east of Betelgeuse
Comet 4P/Faye puts on a faint but steady performance this month, passing through a region of sky across Orion’s Club and through to the southwest corner of Gemini. 4P/Faye’s magnitude holds steady at +11.5 all month. Starting its path 9˚ north and slightly east of Betelgeuse (Alpha (a) Orionis), the comet tracks east in October, gaining a more southeast trajectory at the month’s end to position it a little over a degree south of mag. +3.3 Xi (x) Geminorum. As a handy guide to sky distance, the apparent separation of Rigel (Beta (b) Orionis) and Mintaka (Delta (d) Orionis) is 9˚, while the gap between Xi and 30 Geminorum – the mag. +4.5 star slightly northwest of Xi – is half a degree.
4P/Faye is a periodic comet with an orbital period of 7.55 years. It’s a Jupiter-family comet, a class which describes comets with a period of less than 20 years and orbital inclinations less than 30˚. Faye’s orbit takes it in as close as 1.666 AU from the Sun at perihelion and out as far as 6.026 AU at aphelion. The last perihelion occurred on 8 September of this year.
4P/Faye is named after Hervé Faye, a French astronomer who first observed the comet on 23 November 1843, with confirmation coming on the 25th. The discovery was made
possible because the comet was passing close to Earth at the time, making it appear bright.
This month, 4P/Faye is best seen with medium to large telescopes. Smaller instruments should be able to pick it up in a dark sky. Its position north of Orion is favourable, this area of sky reaching greatest altitude in the early hours of the morning.