Notes on the Active Galactic Nuclei Observing Program
Active Galactic Nuclei (“AGN”) are a special class of galaxies that have especially active cores, or nuclei. You can read more about them here and here. Though there are several type of AGNs, three of the main types are included in this program: Quasars, Seyfert Class Galaxies, and BL Lacertae Objects. While some of the galaxy targets in this program are quite large, others a very small — so small they are difficult to identify in a regular astro photo.
The larger galaxies are easy to track down and identify. To identify the smaller ones, I used a process called “plate solving” that uses sophisticated software to compare the photo in question to a database of the entire sky to identify the location and objects in the photo. For the larger galaxies, I turned to the online resource Nova Astrometry. For smaller galaxies, I used the plate solving and annotation scripts in Pixinsight. I also used Pixinsight to stack, improve, and enhance the photos. When feasible, I identify galaxies or stars that are adjacent to the target galaxy.
I have taken these photos using a remote photo service called Slooh. Slooh employs a number of telescopes but I have found I got the best results with the “Slooh 2” scope in Santiago, Chile, which is designated “SC 2” in the photo notes. You can read about the scope and camera here. In a few cases I utilized a Slooh scopes in the Canary Islands called “Canary 3.” I designate these as “CL 3” in the photo notes. You can read about the scope and camera here.
I have also included links to SIMBAD (the Set of Identifications, Measurements, and Bibliography for Astronomical Data) operated by the Centre de Données astronomiques de Strasbourg (CDS), and links to Wikipedia. (Wikipedia does not have pages for some of the dimmer targets. In those cases I simply omit the Wikipedia link.) These provide additional information about the object in question.
The notes that accompany each photo contain the following information: Identifier(s) of the galaxy, its visual magnitude, its position in the sky (using Right Ascension and Declination identifiers), its distance from planet Earth, the telescope used to take the photo, the date and time of the exposure, and at the Simbad and Wikipedia links.
NB: A note about filters. Slooh telescopes and cameras operate on fixed filter / exposure formulas based on the type of target in question. Sometimes it takes luminance-only shots and at other times it takes separate L,R,G, and B photos. I used a variety of integration techniques for the photos in this program. In general, if the photo has color in it, it is RGB. If it is monochrome, it is a luminance shot. In all cases, Slooh returns Luminance shots with 50 second exposures and R, G, and B shots with 20 second exposures.