ALERT! Comet C/2015 ER61 PanSTARRS is in Outburst
Wednesday, April 5, 2017 at 7:01PM
Ian Musgrave in Alerts, C/2015 ER61, Comet, Comets, alert

Path of comet C/2015 ER61 as seen from SSO an hour before astronomical twilight in the morning. The large rectangle is the FOV of T8, the small that of T9. Click to embiggen.

Comet C/2015 ER61 is confirmed to be in outburst, with reports of magnitudes between 7.4 and 6.5, up from a pre-outburst level of 8.4.

Some nice pre-post image comparisons are here and here

The best view is from the Southern scopes, where the comet is above the lower limits of travel from and hour and a half before astronomical twilight. Unfortunately, for the Northern scopes, the comet is at 19 degrees above the horizon at astronomical twilight, making imaging difficult. From SSO the comet heads towards the horizon passing between Capricorius and Aquarius. It should be a reasonable target for the rest of the month. 

The comet is within wide field view of globular cluster M72 and open cluster M73 over the next two days, and the Saturn Nebula on the 9th. The comet moves relativel fast so stacking several short exposures may be best.

The MPEC one line ephemeris is:

    CK15E61R  2017 05 09.9428  1.042123  0.997309   68.1953  235.2184    6.3489  20170216  11.0  2.0      C/2015 ER61 (PANSTARRS)

Article originally appeared on Remote Internet Telescope Network - Online Imaging & Telescope Hosting Service (
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