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(meteorobs) Hale Bopp nucleus



About the nucleus of Hale Bopp
> February 16.42UT: Coma's magnitude (m1) = 1.5 with unaided eye, while
> 16-inch reflector @170x shows two subsidiary nuclei or mass ejections,
> first 9" from the primary nucleus in p.a.195 (S), the other 21" from
> nucleus in p.a. 225 (SW). These are at opposite edges of the bright 
dust
> fountain coming off the primary nucleus.
> J.Bortle
>I was out this morning observing the comet through my 16". I can verify
>what Mr. Bortle is saying as the nucleus looked doubled and somewhat
>"potato-shaped" at high magnifications. The south end had an intense
>fountain of material creating the brightest portion of the dust tail.
>The yellow color has faded somewhat to a "creamy off white". It was too
>bright to estimate tail length but the naked eye magnitude of the coma
>was estimated at +1.4.
>Bob Lunsford

The (pseudo) nucleus of Hale Bopp seems to show a cyclical variation 
in shape. On 28 January observing with my 8" reflector  (around 
06.00UT) I noticed an elongated nucleus, then 31 January, an almost stellar 
looking nucleus. February 3rd the nucleus looking elongated again.
Presumably this must reflect some rotatory movement of the nucleus concealing
and revealing a major jet. February 5 the nucleus was irregular 
and fuzzy looking.
Observing 14 Februaryat 06.24UT there was a bright jet coming from the 
southern side of the  nucleus, which turned a right angle within a 
tens of seconds of arc of emergence. At first it looked very 
puzzling. I watched as the sky brightened and more detail emerged in 
the brightest parts of the coma/nucleus (07.10UT). The bright jet contained a 
sharp oval  condensation like a second nucleus at the point where the 
right angle bend was and at the end of the brigh jet a fuzzier 
condensation.. I may have been mistaken  but the jet seemed to get a 
little bigger and fuzzier as time went on. By February 15 the jet was 
still there and right angled but broader. Several other jets were 
visible in the inner coma.   
It would be interesting to compare everyones' observations and to see 
if there are similar indications of a  rotation period corresponding to the 
changes in the  appearance of the nucleus.
Nick Martin
Ayrshire, Scotland