On the Footsteps of W.P. Fleming Unveiling a Mystery of the Past

At last they were ready. I was holding in my hands all three finder charts for the suspected variables that no one really had observed so far. It took me almost three months to complete this task, which I took on for myself simply out of curiosity, and with a desire to solve a mystery of the years long gone.

It all started when my copy of the Journal of the AAVSO, volume 26, number 2, came in the mail in early 1999. As I always do, I started going through its pages. I went through it in about half an hour and put it in a pile of similar astronomical journals and bulletins to stay there until my next "curiosity moment" when I would be in the mood to read and do more research.

Williamina P. Fleming
Born and raised in Scotland, Williamina Fleming had been a pupil-teacher before coming to America in the latter half of the 19th century. She worked closely with Prof. E. C. Pickering at the Harvard College Observatory and is credited with discovering hundreds of variable stars and helping establish the Pickering-Fleming system - a method of arranging photographic spectra.

I do not remember how long it had been after my first reading of that journal. It occurred to me that I wanted to have another look. I took the journal to work where, during the lunch break, I started to read it, carefully this time. When I turned to page 132, something caught my eye. There it was: a two-page paper by Dr. E. Dorrit Hoffleit of the Yale University Department of Astronomy and Director Emeritus of the Maria Mitchell Observatory. Dr. Hoffleit read the paper at the AAVSO's annual meeting held on October 25, 1997. On the left-hand page she discussed several variables that, due to their spectral peculiarities, were discovered by the astronomer Williamina P. Fleming and her team from the Harvard College Observatory between 1900 and 1911. On the right-hand page there was a table listing fourteen similar variables, which were considered to be favorable candidates for a more extensive investigation.

I was hooked. I immediately started checking to find out whether or not there were variables within the reach of my telescopes (a 3.1" refractor and a 4.25" reflector), and also to see if any one of the variables was visible from mid-northern latitudes (I currently live in Boston).

After about five minutes I was convinced that three suspected variables were easy targets for me and deserved further research: NSV 3379, NSV 11792, and NSV 11913.

The idea of pursuing such an investigation was not new to me. I had made observations of U Gem on November 23, 1990, for a coordinated observing session of the IUE satellite (http://members.aol.com/himenali/astro/article.html). As a variable star observer since 1983, and after joining the ranks of my amateur colleagues at the AAVSO in 1984, one of my dreams had already been realized through this active participation. I realized a second dream on December 1, 1999, when I was one of just ten observers around the world who confirmed the discovery of Nova Aquilae 1999 number 2, V1494 Aql (http://www.aavso.org/alerts/alert264text.shtml).

Now, as a first step in the Fleming variables project, I prepared a checklist of possible resources where I might find more information on these three stars long forgotten. Naturally, the reference list in Dr. Hoffleit's article was a good starting point, so I put some of those resources at the top of my checklist. They were:

• Fleming, W. P., and Pickering, E. C. 1907, Annals of Harvard College Observatory 47, part I, sequence nos. 34 and 150.
• Kholopov, P. N., et al. 1982, New Catalogue of Suspected Variable Stars.
• Walker, A. D., and Olmsted, M. "Identification Charts for 42 Variable Stars Discovered at Harvard." 1958, Pub. Astron. Soc. Pac. 70, 495.
• AAVSO preliminary chart for 1915+17 W Sagittae.

I also included the most contemporary resources in my checklist, such as:

• Millenium Star Atlas by Sky Publishing Corp.
• Space Telescope Science Institute's Digitized Sky Survey (http://stdatu.stsci.edu/dss/)
• Guide CD ROM version 7.0 by Project Pluto
• and of course, the vast Simbad database at the Strasbourg Observatory

As a result of initial checks in the resources I cited above, I found other resources of information on these three stars. These included the following:

• Pickering, E. C., Colson, H. R., Fleming, W. P., and Wells, L. D. "Sixty-four New Variable Stars." 1901, Astrophys. J. 13, 226-230.
• Kazarovets, A. V., et al. "The 74th Special Namelist of Variable Stars." 15 January 1999, Information Bulletin on Variable Stars (Budapest) 4659.
• Makarov, V., et al. "35 New Bright Medium- and High-Amplitude Variables Discovered by the TYCHO Instrument of the HIPPARCOS Satellite." 29 November 1994, Information Bulletin on Variable Stars (Budapest) 4118.
• and three more articles from Astrophysical Journal and Astronomy and Astrophysics.

1. European Space Agency's (ESA) HIPPARCOS satellite had confirmed the variability of both NSV 3379 and NSV 11792.
2. NSV 11792 had been renamed as V1445 Aquilae by the Commission of 27 of the International Astronomical Union.
3. NSV 3379 is one of the 5449 observed by the Infrared Astronomical Satellite (IRAS), and has indications for the existence of a dust shell caused by mass loss in late M-type stars.
4. Other research of OH/IR stars, including NSV 3379, suggested that there definitely is an enlarging dust shell around this variable.
5. MOST IMPORTANT OF ALL, NO ONE HAD EVER OBSERVED THESE VARIABLES VISUALLY!

However, the dice of fate had already been rolled. I was going with my wife, Gamze, to witness the last total solar eclipse of the second millenium from Turkey in August 1999. To coincide with this event, Turkish professional astronomers had decided to hold their annual convention in eastern Turkey, which was on the path of the umbra. While checking with them to select an observing site, Dr. I. Etham Derman (with whom I co-authored a book about Halley's Comet back in 1985) suggested that I submit a research paper on my initial findings on these Fleming variables during that meeting.

Haldun I. Menali has been a member and observer of the AAVSO since 1984. He currently lives in Boston, MA and can be reached at menali@email.com

Unfortunately, since that time, I have not had the chance to observe these stars visually through my scopes. As I am living under the heavily light-polluted skies of Boston, and due to my professional obligations, I am waiting for an opportunity to go under dark skies where I will be able to confirm my charts. Then I am going to observe these three Fleming variables in order to try to unveil the mystery that has lingered since their discovery about a hundred years ago. And this will absolutely result in the presentation of another research paper, as fate might have it!

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