Object of the Week,October 14, 2012 - Cassiopeia A SNR

[RolandosCY]

I saw it few hours ago in my 18" f/4.4 under 6.2 mag skies. Easy to detect at 143x (Denkmeier 14mm) with an OIII filter - looked like a thick arc with even surface brightness.

Good to know Powel! Charts have been prepared, ready for attack tomorrow night if the weather cooperates!

[Uwe Glahn]

Cool object Howard,

better and easier than expected.

10", 143x, UHC, NELM 6m5+
nothing without filter; UHC brings out an round plob in just the place of the brighter arc; a friend and I could hold the glow easily with averted vision; [OIII] to dark

16", 180x, [OIII], NELM 6m5+
brighter arc already without filter; with [OIII] the brighter arc is visible as a curved glow with brighter and thicker E end; two stellar peaks; S arc not visible
CasA.jpg

27", 172x, [OIII], NELM 6m5+
bright even without filter; brighter N arc totally mottled with five stellar peaks; only detail from the S arc is the brightest spot, which could be detected as a very faint stellar spot; no laminar detail

[RolandosCY]

Good to know Powel! Charts have been prepared, ready for attack tomorrow night if the weather cooperates!

Weather 1 - RolandosCY 0!

We started out with excellent conditions at our high altitude site (1300m), with SQM readings peaking at 21.37 overhead in Aries. I had my best ever views of M31, M32, M110, M33, NGC 891, and Taffy 1 galaxies (OOTW Sept 30). Even the Horsehead nebula was detectable without a filter although Orion was just clearing the mountains to the east. Unfortunately, by the time I arrived at this object, the sky grew noticeably brighter (down to 20.90 in Cassiopeia). What's more, even with 18", a lot of objects (especially diffused ones) simply disappeared from the sky. I was totally unable to spot Cas I, and although I made a new, detailed sketch of the Taffy 1 galaxies (with the "hook" plainly visible), after checking them out again they just were not there! Later on during the day I found out from the local Met Office that a thick layer of high-level humidity moved in around 01.00 local time ahaead of a major low pressure system, thus reducing contrast considerably and rendering lsb and faint targets practically invisible. Oh well... We'll give it a go in two weeks!