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Obtaining Charts.
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A method for identifying a possible supernova in the target
area. The target area that we are concerned with in this study has a few
problems....in that there isn't an abundance of literature available for
the individual to access in search of photographs of the target galaxies,
and magnitude sequencing of stars around these galaxies. Ah! but there is
an alternative....however, a bit of work is involved to acquire these
tools.
The process involved has been used for years by the master visual supernova discoverer...The Rev. Robert O. Evans of Coonabarabran, Australia. In fact his inspiration has been passed on to Dana Patchick of California (discoverer, 1987L) who accomplished a similiar feat....this utility is the photographing of the Palomar Sky Survey (in Rev. Evans case additional surveys were also made available to him) into a slide format! The idea is to have access to an astronomical library that has a collection of the POSS (Palomar Sky Survey) plates, then construct a macro lens attached to a 35mm-camera to accomplish close-up views and snapshots of individual galaxies. In proceeding in this manner you cut down on the costs of actually having to purchase the charts (available from Cal-Tech for $36 for 6 plates[note: this price may have gone up, but that was the price a few years ago]. Rev. Evans has thousands of such slides, Dana has spent a year getting several hundred to a thousand images for use at the telescope and for reference. The main idea for this project was to have a ready reference available in the event some star was spotted that appeared "out of place" near or involved in some galaxy. Like any experienced observer these gentlemen have enough skill to be able to visually estimate [within a few tenths of a magnitude] a particular star. (that is why the experienced observer would stand a better chance at this project than one who is not familiar with making magnitude estimates). While this regimen has some pitfalls it provides a "rough" ready reference that will give the observer some satisfaction that he is able to "weed" out any stars that might already exist near some galaxy, and that he will not have to call someone long distance on the telephone to verify some spurrious object....in essence you then become somewhat self-sufficient in the verification department. In the event that some object is observed that is not part of the photo then the excitement to call other verifiers is initiated.(one note of caution to photographic initiatives....photographic aperature photometry is not a valid method of magnitude sequencing unless you have had some experience. Even then this is not recommended as a difinitive solution to stellar sequencing estimation ). OTHER REFERENCE SOURCES Reference photographs (no sequencing) of the target galaxies (with the exception of 27 galaxies) can be found in the Deep Space CCD Atlas: North, by John C. Vickers.(6) They are images which employed a 14" SCT, and exposed for, from 30 to 90 seconds using a CCD camera. If making your charts proves too tiresome you can check the ![]() |