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Comet Encke

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20 years 5 months ago #1063 by albertw
Comet Encke was created by albertw
I've uploaded a finder chart for the next week or so to the files section www.irishastronomy.org/user_resources/fi...1068501129-Encke.pdf

Cheers,
~Al

======================================================================
BAA electronic circular No. 00122 www.britastro.org/
======================================================================

Comet Encke is now visible in binoculars, at least from a dark sky site. The
comet is very large and diffuse and hence does not show up well in large
telescopes. By contrast in binoculars it is a relatively easy object. I
observed it from Cambridge with the 0.30-m Northumberland refractor x185 on
October 27.01, making it a very difficult 12.4, with a 1.4', DC1 coma.
Observing with 20x80 binoculars from outside Cambridge on October 27.94 I made
it 9.9, with a 4.5', DC3 coma. It was an easy object in 25x100 binoculars.
The comet will continue to brighten during November and may reach 6th
magnitude in early December. The comet is visible in the early evening and the
moon will be out of the way from mid-week until November 27. The Section web
page at www.ast.cam.ac.uk/~jds will give updates on comet Encke and
other comets as available.

Jonathan Shanklin
Director, Comet Section

j.shanklin@bas.ac.uk
British Antarctic Survey, Madingley Road, Cambridge CB3 0ET, England
www.antarctica.ac.uk/met/jds
www.ast.cam.ac.uk/~jds

======================================================================
BAA electronic circulars service. E-mail: circadmin@britastro.org
Circular transmitted on Mon Nov 10 11:44:37 GMT 2003
(c) 2003 British Astronomical Association www.britastro.org/
======================================================================

Albert White MSc FRAS
Chairperson, International Dark Sky Association - Irish Section
www.darksky.ie/

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20 years 5 months ago #1077 by John OBrien
Replied by John OBrien on topic Re: Comet Encke
Mmmm.... will have to look out for this when the moon is out of the way!

Do you know if there is any possibility of seeing an extended comet tail?

"We are the music makers ... and we are the dreamers of dreams." - W.W.

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20 years 5 months ago #1091 by michaeloconnell
Replied by michaeloconnell on topic Re: Comet Encke
Tried to observe Encke last night. I used focal reducer and 32mm eyepiece in order to get as large a FOV as possible. Poor seeing conditions and moonlight interfering. However, did manage to observe it. It appears much bigger, fainter and more diffuse than I expected. Definetly recommend using as large a FOV as you can possibly manage.
According to Dr. Clay (Arksky Observatory):
"The nucleus of the comet has unexpectedly grown VERY faint now and diffuse compared to its stellar nature only a week ago. The comet is very nebulous and will be quite a sight in very dark skies; try to observe before the moon rises if possible."
Michael

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20 years 5 months ago #1169 by albertw
Replied by albertw on topic Re: Comet Encke
Good luck seeing this...

From: Greg Crinklaw <crinklaws@t...>
Date: Sat Nov 15, 2003 12:26 pm
Subject: Regarding 2P/Encke

This comet has been causing considerable consternation among
observers.
Attention has been drawn to it because it has been the subject of
various magazine articles (written months ago) and the magnitude
estimates from experienced observers at dark sites have been quite
bright. Yet, in truth Encke is a very difficult target this month!

Here's the problem: Encke is very large and diffuse. Some observers
have recently reported the coma to be 15' in diameter (yes, arc
minutes). When making a magnitude estimate the comparison stars are
first defocused to the diameter of the visible coma; defocusing the
stars to 15' will result in very bright estimates (8th magnitude!).
CCD
imaging has tended to miss this large coma, further confusing the
situation.

Spreading that 8th magnitude over such a large surface area results
in a
very low surface brightness. To compound matters, Encke is diffuse so
there is little brightening toward the center. So observing Encke is
akin to observing a faint low surface brightness galaxy (such as the
Fornax Dwarf). The successful detection of such objects follows
somewhat different rules than most deep sky objects; this is one of
the
few cases where aperture usually doesn't win. The key to detection is
contrast (with the sky background). The primary factors that improve
contrast of large low surface brightness objects are (1) a very dark
sky
and (2) a wide field of view.

Those looking for Encke from even a moderately light polluted site are
going to have great difficulty seeing its faint glow against the
skyglow. For at least the next two weeks a dark site is essential.

At the moment the ideal instruments to observe Encke are large
binoculars and small telescopes capable of wide fields of view.
Applying the rule of thumb that the object should ideally subtend no
more than 1/4 the field of view, at least a one degree field of view
is
required. Still larger fields of view will greatly aid detection.

What does Encke look like? At the moment it is little more than a
circular patch of sky that looks ever so slightly brighter than the
background. Users of small wide-field telescopes and large binoculars
at dark sites have the best chance of detection. Larger instruments
can
detect it as well, but it is very difficult. For best results use your
lowest magnification, largest field of view eyepiece.

Clear skies,
Greg

--
Greg Crinklaw
Astronomical Software Developer
Cloudcroft, New Mexico, USA (33N, 106W, 2700m)

SkyTools Software for the Observer:
www.skyhound.com/cs.html

Skyhound Observing Pages:
www.skyhound.com/sh/skyhound.html

Albert White MSc FRAS
Chairperson, International Dark Sky Association - Irish Section
www.darksky.ie/

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20 years 5 months ago #1255 by johnflannery
Replied by johnflannery on topic Re: Comet Encke
observed comet 2P/Encke last night from near Enniskerry (Cloon Wood car park) with 20x60mm binoculars. Time was 18:45UT.

it's very diffuse -- maybe 12 to 15 arc minutes in diameter -- and looks like a large ghostly greyish blur. The fact it's not far from the Coathanger cluster makes it easy to find at the moment by offsetting from the star group. I suspected a slight condensation a little off-centre to PA 80° (actual angle could be wrong) -- but it's easy to convince yourself you want to see something that may not be there.

with the large binocs it's hard not to miss it though slowly sweep to the area it's in because you could easily pass over the comet if a little impatient! Magnitude is just slightly above 8th.

Guy Ottwell's "Astronomical Calendar" for 2003 was saying this is the best apparition of the comet for northern hemisphere observers this century!

a nice clutch of satellites with the naked-eye too passing through Cassiopeia and into Andromeda -- four in quick succession through the area within 20 seconds or so of each other!

no aurora :( -- I think we were getting a little spoilt recently!


John Flannery
SDAS

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20 years 5 months ago #1259 by ei5fk
Comet Encke, No luck
Been out looking through 10*50 binoculars and an 85mm refractor+30mm eyepiece 4 nights recently, no luck whatsoever, However
Vulpecula has been far more interesting, A fox has been visiting my house frequently for the past few months and I have been hand feeding it chips, steak or chicken piceces by hand and milk also during observing sessions, check image at bottom right of linked page
www.qsl.net/ei5fk/astronomy.html

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