The stars of St. John’s
Church Lunenburg, a mystery that I unwittingly discovered and solved after
being approached in June 2004 to provide assistance in designing a replica of
the original star scene that graced the chapel ceiling of the Church. The story
had a long life on the Discovery Channel’s Daily Planet feature, but the
full details were described in a story I wrote for Cassiopeia, the
newsletter of the Canadian Astronomical Society. To view an expanded version of
the story, click here. 
Research interests:
Young
to intermediate age open clusters. Most of my research involves very sparse
clusters and groups associated with Cepheid variables, but I am also interested
in very young clusters that contain Wolf-Rayet stars or pre-main-sequence
objects. Steve Shorlin, who recently (1998) completed his M.Sc. thesis under my
supervision, searched a field in Carina as part of his thesis research, and
discovered a previously undetected young cluster associated with two Wolf-Rayet
stars, one of type WN6 and the other of type WC4. It is the first instance of
both types of objects being found in the same cluster. To view a sample of open
clusters of interest to me, click here. 
Intrinsic
properties of
Cepheid variables and the galactic distance scale. Click here
for a list of open clusters and groups that contain Cepheids as potential
members. In recent years, undergraduate students working with me (Andrew
Horsford, Joseph MacMillan, and Stephen Goobie) have observed Cepheids with the
CCD camera on the 0.4-m telescope of the Burke-Gaffney Observatory, and have
added valuable data on period changes for these stars. The derived period
changes primarily reflect stellar evolution through the Cepheid instability
strip, but also help to specify the pulsation modes of the stars. For more
details on our use of the campus telescope, click here. 
Observable properties of interstellar and circumstellar extinction. Much of my
early work focused on the use of the variable-extinction method to derive
values for the ratio of total-to-selective extinction, R, in open
clusters and associations. Roughly 60 or so open clusters yield fairly normal
values of R = 3.1, plus or minus 0.4, but there are a few regions where
anomalously large values of R, i.e. 4 or 5, seem to exist.
Galactic structure, when I can find time for it.
Honours:
Clockwise from upper left: President’s Award for Excellence in Research
presented by President Dr. Kenneth Ozmon at Saint Mary’s University’s Fall
Convocation (October 1997), Service Award of the Royal Astronomical
Society of Canada presented by Randy Attwood (June 2001), Founding Member
Special Award of the Sudbury Astronomy Club presented during the Club’s
20th Anniversary celebrations (November 2001), Distinguished Alumnus of the
Year award by Renison College (University of Waterloo) at its 45th Founders’
Day ceremony (January 2004), Asteroid 27810 Daveturner (= 1993 OC2) (not
exactly as illustrated) named by Carolyn Shoemaker and David Levy (November
2003).
(Hi Brandi!)
Email: turner(“at”)ap.smu.ca
Phone: (902) 420-5635
Fax: (902) 496-8218
Recently Published Articles:
2020
Usenko, I. A., Miroshnichenko, A. S., Danford, S., Kovtyukh, V. V., and
Turner, D. G. 2020, Spectroscopic Investigations of the Polaris (α UMi)
System: Radial Velocity Measurements, New Orbit, and Companion Influence for the
Cepheid Polaris Aa Pulsation Activity, Odessa Astronomical Publications,
33, 65-71
Usenko, I. A., Kniazev, A. Yu., Katkov, I. Yu., Kovtyukh, V. V., Mishenina,
T. V., Miroshnichenko, A. S., and Turner, D. G. 2020, Spectroscopic
Investigations of Galactic Clusters with Associated Cepheid Variables. IV.
Collinder 394 and BB Sgr, Odessa Astronomical Publications,
33, 58-64
Turner, D. G. 2020, The Lost Planets: Peter van de Kamp and the
Vanishing Exoplanets Around Barnard’s Star (John Wenz: M.I.T. Press, 2019),
Journal of the Royal Astronomical Society of Canada, 114, 234-237
2019
Usenko, I. A., Kniazev, A. Yu., Katkov, I. Yu., Kovtyukh, V. V., Mishenina,
T. V., Miroshnichenko, A. S., and Turner, D. G. 2018, Spectroscopic
Investigations of Galactic Clusters with Associated Cepheid Variables. III.
Collinder 394 and BB Sgr, Odessa Astronomical Publications,
32, 91-96
2018
Usenko, I. A., Kniazev, A. Yu., Kovtyukh, V. V., Mishenina, T. V.,
Miroshnichenko, A. S., Turner, D. G., and Protsyuk, Yu. I. 2018,
Spectroscopic Investigations of Galactic Clusters with Associated Cepheid
Variables. II. NGC 5662 and V Cen, Odessa Astronomical Publications,
31, 117-122
Usenko, I. A., Miroshnichenko, A. S., Danford, S., Kovtyukh, V. V.,
Turner, D. G., Shul’ga, A. V., and Protsyuk, Yu. I. 2018, Spectroscopic
Investigations of Galactic Clusters with Associated Cepheid Variables. I. Polaris
Cluster and α UMi, Odessa Astronomical Publications, 31, 113-116
Majaess, D., Dékany, I., Hajdu, G., Minniti, D., Turner, D. G.,
and Gieren, W. 2018, Establishing the Galactic Centre Distance Using
VVV Bulge RR Lyrae Variables, Astrophysics and Space Science, 363,
127, 1-6
2017
Turner, D. G., Carraro, G., and Panko, E. A. 2017, On the Existence
of Young Embedded Clusters at High Galactic Latitude, Monthly Notices of the
Royal Astronomical Society, 470, 481-488
Carraro, G., Turner, D. G., Majaess, D. J., Baume, G. L., Gamen, R.,
and Molina Lera, J. A. 2017, Extinction in the Star Cluster SAI 113 and
Galactic Structure in Carina, Astronomical Journal, 153, 156, 1-11
2016
Majaess, D., Turner, D. G., Dékany, I., Minniti, D.,
and Gieren, W. 2016, Constraining Dust Extinction Properties
via the VVV Survey, Astronomy and Astrophysics, 593, A124, 1-7
Turner, D. G. 2016, The Scale of Reddening for Classical
Cepheid Variables, Revista Mexicana de Astronomía y
Astrofísica, 52, 223-239
Carraro, G., Seleznev, A. F., Baume, G., and Turner, D. G.
2016, The Complex Stellar Populations in the Lines of Sight
to Open Clusters in the Third Galactic Quadrant, Monthly Notices
of the Royal Astronomical Society, 455, 4031-4045
2015
Dambis, A. K., Berdnikov, L. N., Efremov, Yu. N., Kniazev,
A. Yu., Rastorguev, A. S., Glushkova, E. V., Kravtsov, V. V.,
Turner, D. G., Majaess, D. J., and Sefako, R. 2015,
Classical Cepheids and the Spiral Structure of the Milky Way,
Astronomy Letters, 41, 489-500
2014
Turner, D. G., Majaess, D. J., and Balam, D. D. 2014,
Testing New Ideas Regarding the Nature of Interstellar
Extinction, Canadian Journal of Physics, 92, 1696-1702
Majaess, D., Turner, D. G., Gieren, W., and Ngeow, C.
2014, Evidence for Photometric Contamination in Key Observations
of Cepheids in the Benchmark Galaxy IC 1613, Astronomy and
Astrophysics, 572, A64, 1-5
Turner, D. G. 2014, An Eclectic View of our Milky
Way Galaxy, Canadian Journal of Physics, 92, 959-963
Bartlett, D. J., and Turner, D. G. 2014, Einstein
versus Schwinger: Who is Right About Gravity?, Canadian
Journal of Physics, 92, iii
Majaess, D., Carraro, G., Moni Bidin, C., Turner, D. G.,
Bonatto, C., Moyano, M., Berdnikov, L., and Costa, E. 2014,
On the Crucial Cluster Andrews-Lindsay 1 and a 4% Distance
Solution for its Planetary Nebula, Astronomy and Astrophysics,
562, A1, 1-6
Berdnikov, L. N., Turner, D. G., and Henden, A. A. 2014,
A Search for Evolutionary Period Variations of Cepheids Using
the Harvard Plate Stacks: FF Aql, Astronomy Reports, 58,
240-248
Moni Bidin, C., Majaess, D., Bonatto, C., Mauro, F.,
Turner, D. G., Geisler, D., B., Chené, A.-N., Gormaz-Matamala,
A. C., Borissova, J., Kurtev, R. G., Minniti, D.,
Carraro, G., and Gieren, W. 2014, Investigating
Potential Planetary Nebula/Cluster Pairs, Astronomy
and Astrophysics, 561, A119, 1-14
2013
Turner, D. G. 2013, Towards a Determination of
Definitive Parameters for the Long Period Cepheid S
Vulpeculae , Odessa Astronomical Publications, 26, 115-119
Majaess, D., Carraro, G., Moni Bidin, C., Bonatto, C.,
Berdnikov, L., Balam, D., Moyano,M., Gallo, L., Turner, D. G.,
Lane D., Gieren, W., Borissova, J., Kovtyukh, V., and Beletsky,
Y. 2013, Anchors for the Cosmic Distance Scale: the
Cepheids U Sgr, CF Cas and CEab Cas, Astronomy and
Astrophysics, 560, A22, 1-8
Turner, D. G. 2013, Deriving Definitive Parameters
for the Long Period Cepheid S Vulpeculae, Journal of the
American Association of Variable Star Observers, 41, 390
(abstract)
Majaess, D. J., Turner, D. G., and Gieren, W. 2013,
On the Form of the Spitzer Leavitt Law and its Dependence on
Metallicity , Astrophysical Journal, 772, 130, 1-6
Majaess, D., Sturch, L., Moni Bidin, C., Soto, M., Gieren,
W., Cohen, R., Mauro, F., Geisler, D., Bonatto, C., Borissova,
J., Minniti, D., Turner, D. G., Lane, D., Madore, B., Carraro,
G., and Berdnikov, L. 2013, Anchors for the Cosmic
Distance Scale: the Cepheid QZ Normae in the Open Cluster NGC
6067, Astrophysics and Space Science, 347, 61-70
Turner, D. G., Kovtyukh, V. V., Luck, R. E., and Berdnikov, L. N.
2013, The Pulsation Mode and Distance of the Cepheid FF Aquilae, Astrophysical
Journal Letters, 772, L10, 1-5
Carraro, G., Turner, D. G., Majaess, D. J., and Baume, G. 2013,
The Distance to the Young Open Cluster Westerlund 2, Astronomy and
Astrophysics, 555, A50, 1-9
Turner, D. G. 2013, Deriving Definitive Parameters for the Long
Period Cepheid S Vulpeculae, American Association of Variable Star Observers,
Spring Meeting
Majaess, D. J., Turner, D. G., Gieren, W., Berdnikov, L. N., and Lane, D. J.
2013, On the Metallicity Dependence of Classical Cepheid Light Amplitudes,
Astrophysics and Space Science, 344, 381-388
Turner, D. G., Kovtyukh, V. V., Usenko, I. A., and Gorlova, N. I.
2013, The Pulsation Mode of the Cepheid Polaris, Astrophysical Journal
Letters, 762, L8, 1-4
Submitted papers and papers in preparation (for preprints contact author):
Turner, D. G., Usenko, I. A., Miroshnichenko, A. S., Klochkova,
V. G., Panchuk, V. E., Yang, S. L. S., and Gregory, P. C. 2016, The
Dynamical Challenges of the Polaris System, Celestial Mechanics and Dynamical
Astronomy, in preparation
Turner, D. G. 2016, Recovery of the Interesting Open Cluster
Collinder 464, Astronomische Nachrichten, in preparation
Previous Positions:
Postdoctoral Fellow, University of Toronto (1974-1976)
Assistant Professor, Laurentian University (1976-1978)
Assistant Professor, University of Toronto (1978-1980)
Assistant/Associate Professor, NSERC University Research Fellow,
Laurentian University (1980-1984)
Teaching (courses I have taught at Saint Mary’s):
ASTR 1100.2 Introduction to Astrophysics
AST 202.0 Introductory Astronomy for Science Students
AST 205.1 General Astronomy I
AST 206.2 General Astronomy II
AST 215.1(.2) The Sky and Planets
AST 216.1(.2) Stars and Galaxies
AST 306.1(.2) Observational Astronomy
AST 2100.1 Foundations of Astrophysics
AST 2312.1(.2) Foundations of Astrophysics
AST 2313.1(.2) Properties of Stars
ASTR 2400.2 Physics of Stars
AST 316.1(.2) Stellar Astronomy
AST 3412.1(.2) Interstellar Matter and Stellar Evolution
AST 3500.1(.2) Galaxies and Cosmology
AST 416.1(.2) Astrophysics II
AST 445.1(.2) Solar System Astronomy
AST 602.1(.2) Galactic Astronomy
ASTR 5500.1(.2) Galactic Astronomy
ASTR 5602.1(.2) Galactic Astronomy
AST 607.1(.2) Binary and Variable Stars
AST 611.1(.2) Directed Readings in Current Literature
AST 695.1(.2) Graduate Seminar I
ASTR 5695.1(.2) Graduate Seminar I
AST 696.1(.2) Graduate Seminar II
AST 697.0 Research Project in Astronomy
ASTR 5690.1 Research Methods I
AST 698.0 Thesis
ASTR 6698.0 Thesis
ASTR 8990.0 Doctoral Dissertation
PHY 210.1/211.2 University Physics I, II (various lab sections)
PHYS 1210.1/1211.2 University Physics I, II (various lab sections)
PHY 305.1(.2) Newtonian Mechanics
PHYS 2301.2 Newtonian Mechanics
PHYS 2305.1(.2) Newtonian Mechanics
PHY 500.0 Research Thesis
Updated December 2020.
David G. Turner, Professor Emeritus
Astronomical
phenomena that can be viewed with the unaided eye, such as sunrises, sunsets,
auroral displays, planetary conjunctions, first sighting of the thin crescent
of the Moon following New Moon (occasionally Ramadan in North America begins as
a result of a sighting through my office window), etc. A lot of
astronomy can be done without telescopes or binoculars. To view a sample
selection of images and drawings, click here. 
The Star of
Bethlehem, a subject in which I became interested during the six years I spent
as Director of the Doran Planetarium, Laurentian University, where each year I
scripted and produced Christmas Star shows for the general public. The
mystery of the Star of Bethlehem is an historical, as well as astronomical,
puzzle. To read a fictional article on the Star of Bethlehem that I wrote for
the Saint Mary’s Maroon and White, click here. 