Re: [BAA Comets] Comet 17P/Holmes has gone into outburst !! Nick James (09 Aug 2021 21:43 UTC)
Re: [BAA Comets] Comet 17P/Holmes has gone into outburst !! Richard Miles (09 Aug 2021 21:50 UTC)

Re: [BAA Comets] Comet 17P/Holmes has gone into outburst !! Nick James 09 Aug 2021 21:43 UTC

Richard,

Thanks for the alert.

The formatting seems to be messed up on your comets-ml message but I
think it says that the comet was 17.30 on July 20 and 16.02 on August 8.
How did you determine the time of the outburst as Aug 3?

My last image of it was on July 29 when it was around mag 17.0
(unfiltered vs Gaia DR2 G) in a 9 arcsec radius aperture:

https://britastro.org/cometobs/17p/17p_20210729_020259_ndj.html

Morning objects are not good for me on weekdays but I'll have a go at it
next time I get a chance.

Nick.

On 09/08/2021 22:05, Richard Miles - rmiles.btee at btinternet.com (via
baa-comet list) wrote:
> 17P/Holmes is well known for its unique 13-14 magnitude mega-outburst of
> 2007 October 24.
> This enormous outburst did not disrupt its nucleus, which appears to be
> still intact.
>
> On or about 2021 August 03, the comet was just 3 degrees away from
> reaching the same position in its orbit when it underwent its dramatic
> mega-outburst of 2007. During the intervening years, it has made not
> quite two orbits of the Sun.
>
> The current outburst looks to be 1.4 magnitudes amplitude, meaning that
> it has brightened by almost a factor of 4, i.e. a very significant event
> indeed.
>
> We might expect some repeat small outbursts every 36-44 days.
>
> More details have been posted on the 'comets-ml' mailing list at:
>
> https://groups.io/g/comets-ml/message/29901
>
> Richard Miles
>
> To unsubscribe from this list please go to
> http://www.simplelists.com/confirm.php?u=Aj4vCBHI6JSRpYRB2DWvMTYlWL2vuAnC