I had a visual view last night in my 12" Mewlon. Overall visually it's a very diffuse elongated oval but I could also see the brighter core (x135). I could just detect Y4 in the 4" Apo.

It is fascinating to observe comets going through these changes. Also had good views of T2 and Y1 (these were easy in the 4".)

Andrew

-----Original Message-----
From: baa-comet@simplelists.com [mailto:baa-comet@simplelists.com] On Behalf Of Nick James
Sent: 11 May 2020 22:37
To: baa-comet@simplelists.com
Subject: [BAA Comets] C/2019 Y4 (ATLAS) developments

My preliminary image from tonight taken in very bright twilight shows that the central coma region of this comet continues to brighten, up from 13.9 in an 11 arcsec radius aperture on May 9.9 to 13.5 tonight.
Also the bright inner coma has become significantly extended in the tailwards direction.

The comet is moving very quickly now (2.6 arcsec/min) so keep exposures short. I have been using 20 sec which corresponds to 0.9 arcsec trailing. My images tonight have an FWHM of 2".4.

Please note that in an earlier email I gave the wrong address for posting images to the BAA archive. It should be cometobs@britastro.org
*NOT* britastro.com.

Nick.
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