[AZ-Observing] Re: McNeil's Nebula Images

McNeil recently posted an excellent follow up image to
alt.binaries.pictures.astro he took of  M78 and Hartmut Frommmert of SEDS
brought up the fact the nebula was found in earlier photographs.  McNeil
posted this reply pointing out that although it is not 'new', noone else
noticed it:


----- Original Message ----- 
From: "Jay McNeil" <icnebulae@xxxxxxxxxxx>
Newsgroups: alt.binaries.pictures.astro
Sent: Thursday, February 19, 2004 3:53 PM
Subject: Re: Re: ASTRO: Messier 78 with new neb


 Hi Hartmut,

 Thanks for the kudos, and...
 Yes, the object is obviously visible on the Kreimer's 1966
 image.  Furthermore, on the far-red/nir plate scans one can
 see a very faint stellar counterpart to IRAS 05436-0007. As
 a matter of fact, this object is very bright on the older
 2MASS images. Furthermore, HH 22 (which happens to lie in
 the exact same direction as part of the new nebula)also
 shows as a small nebulous "blob" on deep images taken of
 the area with infrared sensitive equipment. HH22 is
 actually _just_ visible on the downloadable red scans even.
 The fact that the young "stellar" object presently
 undergoing eruption has existed and been known about for
 some time is not a matter of argument--the fact that it
 (and the resulting nebula) went from being all but invisible
 in the optical range to one of the more conspicuous objects
 in the entire field over a period of less than 3 months is
 what's so striking and phenomenal about the discovery!

 And regarding the earlier (1960's) images that distincly
 show the object, it has been speculated for some time now
 by Reipurth, Herbig, and others that such pre-main sequence
 eruptions are indeed periodic in nature. The fact is,
 however, that so "few" of these eruptions have ever been
 captured this early on--I had read somewhere that the going
 rate is one such observation every 6 to 7 years thus far.
 Now, let's combine that with our complete lack of knowledge
 regarding these speculated "periods" between such eruptions
 for a given young stellar object. FU Ori went form mag 16
 to 10 (where it still hovers nearly 70 yrs later) in just a
 few months. Meanwhile, V1515 Cyg took several decades to
 increase by only 4 mags. The rise and fall times of such
 eruptions thus far recorded vary dramatically, just as the
 periods between subsequent eruptions are specualted to vary
 as well. So, in essence, it would actually make sense if
 this star underwent a similar eruption some other time
 within the past century. If this is proven so, then I
 personally don't see that as being any sort of "negative"
 aspect to my finding--just a very staggering achievement in
 the calculation of such outbursts.<g>

    With all sincerety, I was simply looking at the right
 place at the right time--as with most amateur discoveries.
 On the other hand, I have learned through experience
 that "anyone" with enough money (to purchase the proper
 equipment) and patience can take a suprisingly good CCD
 image.  However, knowing exactly what is going on inside
 your image enough to realize that a peculiar 1' diameter
 object doesn't "normally" belong there is not something
 that I take for granted.  After all, if the guy snapping
 the Palomar Optical Sky Survey shots would've known that
 George Abell would come along shortly after and find some
 2712 new galaxy clusters and 86 new nebulae using his
 prints, he would've likely been waiting outside the
 darkroom door with a magnifiying glass in hand as the
 plates were being developed!  <G>

 Jay McNeil

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