Observation Alert: Extremely bright mag 12.2 outburst of Comet 29P

September 24, 2018
A second outburst of 29P/Schwassmann-Wachmann has taken place on 2018 09 23.2 +/-0.1 which has raised its brightness from r mag 13.2 to 12.2. This new outburst occurred 2.6 +/-0.2 days after this first event and its current brightness makes it one of the four most intense outbursts in 8 years.

Prior to my checking latest images, I had decided to send an alert that further outbursts of this comet are very likely in the coming days.
This event has exceeded even those predictions.

It is expected that one or more weaker outbursts will also occur during the next 10 days.

For the next couple of days the comet will be situated close (10-15 deg) to a nearly Full Moon.

Observers are encouraged to keep 29P under close surveillance. Spectroscopic follow-up, especially in the near- and mid-infrared would be appreciated.
ALMA observations in the submillimeter range are also encouraged given that we have now witnessed a very rare bright double outburst.

Richard Miles
Brirish Astronomical Association