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Searching for Arakelian

How to add Obscure Objects to your SkyTools 3 Observing List

Astronomical designations are one of the more fun and interesting aspects of our hobby.  But the large number of obscure or arcane catalog identifiers can lead to frustration when creating your own SkyTools observing list.  This guide will explain how to go about dealing with this problem.

But first a little perspective.  Why doesn't SkyTools simply have all the catalog designations in it so I can type in Arakelian 320 and get my galaxy directly?  The answer has to do with how professional astronomers work and how designations come about in the first place.

The Swartz Galaxies

Once upon a time there was a graduate student at the University of Illinois names Swartz.  His dissertation had to do with modeling the rotational velocities of galaxies.  He spent many late nights eating pizza and Top Ramen at his desk creating a computer model.  In order to test his computer model his advisor got him time on a big telescope in Texas.  But first he needed targets: galaxies that are very close to being edge on.  Swartz poured through the catalogs and online databases looking for appropriate galaxies and compiled a list as he went.  All of these galaxies were already known and had designations such as NGC, UGC and MCG.  Eventually he finished his dissertation and published his work in the Astrophysical Journal.

Years later an amateur astronomer named Jones got to talking to a woman at a star party.  She had gone to school with Swartz.  They were observing a nice edge-on galaxy in Jones' Dob.  One thing lead to another and she mentioned that Swartz had compiled a list of edge-on galaxies.  When Jones got home he looked up Swartz's paper and ended up writing an article for Sky & Telescope titled, "Observing the Swartz Galaxies."  His table in the article naturally listed these galaxies as Swartz 1 through Swartz 24 and he gave positions and other data for each.

Meanwhile Swartz's original table published in the ApJ ended up in the hands of a guy who works for the NASA/IPAC Extragalactic Database project (otherwise known as NED).  He diligently went about adding the Swartz galaxies by number to NED.  But he ran into a problem.  Another astronomer named Swartz had already created a "catalog" of objects and the Swartz designation was already in use.  So he shortened Swartz to Swz for this new catalog, listing Swz 1 through Swz 24 in the database.

Along comes a guy named Andy who is really excited about creating an observing list for his club's nationally recognized star party.  He comes across the article about Swartz galaxies in Sky & Telescope and decides to add Swartz 13 to his list, which is published prior to the event.

Finally we have Paul.  Paul recently bought SkyTools 3 and he's excited about using it at the upcoming star party.  He sets about creating a SkyTools observing list with the objects that Andy selected.  But when he comes across Swartz 13, SkyTools can't find it.  So he asks a friend what to do and his friend suggests using NED, which can be accessed online.  He types Swartz 13 into NED and gets a galaxy that isn't even visible from the latitude of the star party.  Why? Because NED uses "Swartz" to identify another catalog. So where the heck is the real Swartz 13 and how does he get it into SkyTools?

Variations of the above fictional scenario play out continually, leading to large numbers of obscure catalog identifiers that normally wouldn't ever be used in practice, but for one reason or another are included in a list of objects to observe.  Often it's simply that the author finds the obscure designation (like Swartz 13 or Arakelian 320) to be more interesting so he uses it in his article.  In his mind he's published everything the observer needs to find it because he included the position.  But with the increasing use of software planning tools the author has in fact left the reader to make an involved search for the object by not including the more common identifier.

How to add Obscure Objects to your SkyTools Observing List

There are three reasons why SkyTools might not recognize an object designation:

  1. The designation isn't formatted the way SkyTools expects
  2. The catalog is so obscure that cross references are not included for it
  3. The object is so obscure that it is missing from the SkyTools database entirely

To the first issue: from my fictional example above one can see that there is no standard for catalog identifiers.  It could be Swartz or Arakelian  or it could be Swz or Ark, or even something else.  We try to be as accommodating as possible, so that both will be recognized, but it is always an evolving and ongoing process.  To see the format expected for designations in SkyTools open the Object Requestor, select the type of object you are looking for and browse the designations available.  A list will appear for each type on the right.  If you can format the designation the way it appears you will have a high chance of success via the Quick Search.

Sometimes an object with a well-known designation is referred to only by an obscure designation that SkyTools does not recognize.  There are two online tools available that can help you look up the object via the obscure designation.

SIMBAD is an extensive database of all types of astronomical objects.  It has most of the obscure designations but there are so many that they are often given very obscure  formats such as, ZW VII 421.  So it can take some effort to use this tool to find your object.

NED is an extragalactic database best used for galaxies and quasars.  It is limited to these types of objects but is more complete and more definitive than SIMBAD. 

If you can find your object using one of the above tools, enter one of the many cross identifications they list into SkyTools and go from there.

If you cannot find a cross reference to a catalog identifier recognized by SkyTools then the next approach is to use the coordinates provided.  Open the Interactive Atlas.  Click on the target hypertext.  Select the Enter Coordinates tab.   Often you can copy and paste the coordinates into this dialog via the Paste button.  You can also copy/paste the R.A. and Dec. separately by right-clicking in the appropriate edit window and selecting Paste.  Coordinates can of course be typed into the dialog as well.  Click Accept.  Click Ok.

Your object should now appear near the center of the chart.  Double-click on it to see the Object Info. In the case of Arakelian 320 it turns out to be the galaxy UGC 6732.   Select Add Object to Observing List from the Action Menu.

If no object appears at the coordinates, click the Magnitude Limits button on the button bar.  For the type of object you are searching for move the slider all the way to the right.  Check the chart again.  Has it appeared?  If not, then the object isn't in the SkyTools database.  Don't forget to return the magnitude limit to the default.

Finally, you can add objects to SkyTools as a Supplemental Database object .  Open the Data Manager.  Select the Supplemental Data tab.  Select the type of object you wish to add.  Click the Enter New Object button.  Enter the object data and click Ok to close the editor. 

Now open the Designation Search tool and type the designation for the object you created (such as "Swartz 13") into the quick search and press enter.  It should be found.  Now add the object you your list in the usual manner.