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<DIV><FONT size=2 face=Arial>Thanks Denis.</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>The Zwicky Transient Facility (ZTF) has had a
new camera fully operational the last year or so. It is fitted on the 48-inch
Palomar Schmidt used for the Palomar Sky Survey (POSS) and now has almost
a 7deg x 7deg field with 2" fwhm - that's a little larger than the original
14-inch square plates! They can get down to mag 21 in 30 sec and try to
survey the entire northern sky every few nights. The camera reads out in 8
sec. It's like the old POSS but about 1000x faster so it in principle would
repeat the entire POSS (that took several years) in just 24 hours of observing
time. It surveys in g, r and i filters, It has a 1.2-m aperture mechanical
shutter that closes in 0.43 sec!</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>Folks may be interested to learn that I have been
in correspondence with Quanzhi Ye the last week or two, as the team are
going to use automatic detection of Comet 29P's outbursts with ZTF as a way of
rating its discovery performance. As amateurs we keep a very close watch on 29P
for outbursts and seem to successfully detect every such event having
an outburst amplitude of at least 0.4 mag so our data will serve
as one check on how well ZTF detects that type of transient /
interloper.</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>Richard</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
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style="BORDER-LEFT: #000000 2px solid; PADDING-LEFT: 5px; PADDING-RIGHT: 0px; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="FONT: 10pt arial; BACKGROUND: #e4e4e4; font-color: black"><B>From:</B>
<A title=buczynski8166@btinternet.com
href="mailto:buczynski8166@btinternet.com">denis buczynski</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A
title=comets-disc@lists.britastro.org
href="mailto:comets-disc@lists.britastro.org">BAA Comets discussion list</A>
</DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Monday, June 24, 2019 9:00 PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [BAA Comets] Rising from
Ashes or Dying Flash? Mega Outburst of Small Comet 289P/Blanpain in 2013</DIV>
<DIV><BR></DIV>
<DIV
style="FONT-FAMILY: Helvetica Neue, Helvetica, Arial, sans-serif; FONT-SIZE: 16px"
class=ydpc4cb0ca1yahoo-style-wrap>
<DIV></DIV>
<DIV>Hi Jeremy/all,</DIV>
<DIV>It looks like the author of this paper has just discovered a comet:</DIV>
<DIV><BR></DIV>
<DIV>
<DIV>COMET C/2019 K4 (YE)<BR>Quanzhi Ye, California Institute of Technology,
reports the discovery of<BR>a comet (discovery observations tabulated below)
on CCD images obtained with<BR>the ZTF Camera on the 1.2-m f/2.4 Oschin
Schmidt telescope at Palomar; the<BR>object shows a moderately condensed coma
about 6"-8" in diameter and a broad<BR>tail approximately 40" long to the
northwest (p.a. 310 deg).</DIV>
<DIV><BR></DIV>
<DIV><BR></DIV>
<DIV>Denis Buczynski<BR></DIV></DIV></DIV>
<DIV id=ydpf9c9a127yahoo_quoted_1420000109 class=ydpf9c9a127yahoo_quoted>
<DIV
style="FONT-FAMILY: 'Helvetica Neue', Helvetica, Arial, sans-serif; COLOR: #26282a; FONT-SIZE: 13px">
<DIV>On Monday, 24 June 2019, 17:38:05 BST, Jeremy Shears
<bunburyobservatory@hotmail.com> wrote: </DIV>
<DIV><BR></DIV>
<DIV><BR></DIV>
<DIV>
<DIV id=ydpf9c9a127yiv6891027297>
<DIV dir=ltr>
<DIV
style="FONT-FAMILY: Calibri, Helvetica, sans-serif; COLOR: rgb(0,0,0); FONT-SIZE: 12pt">ApJL
pre-print on ArXiv: <A href="https://arxiv.org/abs/1906.07137"
rel=nofollow target=_blank>https://arxiv.org/abs/1906.07137</A></DIV>
<DIV
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