The comet C/2017 O1 (ASASSN)

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From Fairfield , C/2017 O1 (ASASSN) is visible in the evening sky, becoming accessible at around 20:46 (EDT) as the dusk sky fades, 58° above your eastern horizon. It will then reach its highest point in the sky at 23:05, 77° above your southern horizon. It will continue to be observable until around 04:48, when it sinks to 22° above your western horizon.

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Name C/2017 O1 (ASASSN)
Object Type Comet
Current Position
Constellation:Ursa Major
Magnitude:18.55 (V)[1]
Right Ascension:12h04m [1]
Declination:+28°28' [1]
Distance:5.49 AU
45.63 lightmin [1]
Derived Quantities
Absolute Mag (V):46.42
Orbital Elements[1]
Semi-major axis:375.87 AU
Longitude ascending node:25.80°
Argument of perihelion:20.89°
Epoch of elements:09 April 2019
Mean Anomaly at epoch:0.07°
Derived quantities
Perihelion:1.50 AU
Aphelion:750.25 AU
Orbital period:7287.22 years
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Additional sources

Magnitudes estimates are derived from observations sent into the BAA Comet Section, as compiled by Jonathan Shanklin and last updated on 1 March 2018. We use these amateur observations in preference to the MPC's magnitude estimates, since they are updated much more often. Nonetheless, all comets are intrinsically unpredictable objects, and future magnitude estimates must always be taken with a pinch of salt.




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