About Project

Project name: Binary Systems of South and North (BSN-Project)

Selecting binary systems:
  1. W UMa binary system type.
  2. Range greater than 0.2 magnitudes (easier for inexperienced observers to record useful data)
  3. Period less than 0.4 day (so full the light curve can be recorded in a few nights)
  4. Brighter than V magnitude 13 at minimum.
  5. Observing in more than 2 filters. Especially V and B bands.
  6. Select systems whose light curves have not yet been studied or have been studied in the far years ago.
Project aims:
  1. Times of Minimum to refine period (VSS already has a project on southern eclipsing binaries with this aim, results published annually).
  2. Full light curves in one or more filters for light curve modelling.
  3. O-C diagram to look for apsidal motion, period change, third bodies, etc. (this would require repeated observations over many years).
  4. Understudied or newly discovered eclipsing binaries (surveys such as ASAS, ASAS-SN, SWASP, etc. have discovered many EB’s that should be observed to confirm the type, period, etc.).
  5. Publishing one or more joint papers.

Scientific Committee

  • Atila Poro (Astronomy Department of the Raderon Lab., Burnaby, BC, Canada)
  • Mark G. Blackford (Variable Stars South, Congarinni Observatory, Australia)
  • Edwin Budding (Carter Observatory, New Zealand)
  • Areg Mickaelian (Byurakan Astrophysical Observatory, Armenia)
  • Fahri Alicavus (Çanakkale Onsekiz Mart University, Turkey)
  • Robert (Bob) H. Nelson (Prince George, BC., Canada)
  • Raul Michel Murillo (The Institute of Astronomy, UNAM, Mexico)
  • Mehmet Tanriver (Erciyes University, Turkey)


  • Congarinni Observatory, Australia
  • Byurakan Astrophysical Observatory, Armenia
  • Astronomy Department of the Raderon Lab., Burnaby, BC, Canada
  • Observatory of Adana Çukurova University, Turkey
  • Complejo Astronomico El Leoncito (CASLEO), San Juan, Argentina
  • Variable Star and Exoplanet Section of Czech Astronomical Society, Czech Republic
  • Astrophysics Research Centre and Observatory, Çanakkale Onsekiz Mart University, Çanakkale, Turkey
  • The Institute of Astronomy, UNAM, Mexico
  • Erciyes University, Astronomy and Space Science Observatory Application and Research Center, Kayseri, Turkey


  • Poro, A., Alicavus, F., Fernández-Lajús, E., Davoudi, F., MirshafieKhozani, P., Blackford, M.G., Budding, E., Jalalabadi, B.Z., Rahimi, J. and Farahani, F.A., 2020. BVRI Photometric Observations, Light Curve Solutions and Orbital Period Analysis of BF Pav. Research in Astronomy and Astrophysics, Vol. 21 No. 8. DOI: 10.1088/1674-4527/21/8/203
  • Poro, A., Blackford, M.G., Davoudi, F., Mohandes, A., Madani, M., Rezaei, S. and Bozorgzadeh, E., 2021. The New Ephemeris and Light Curve Analysis of V870 Ara by the Ground-Based and TESS Data. Open Astronomy, 30(1), pp.37-44. DOI: 10.1515/astro-2021-0004
  • Poro, A., Blackford, M.G., Salehian, S.R., Jahangiri, E., Dastjerdi, M.S., Gozarandi, M., Karimi, R., Madayen, T., Bakhshi, E. and Hedayati, F., 2022. The First Photometric Study of AH Mic Contact Binary System. Research in Astronomy and Astrophysics. DOI: 10.1088/1674-4527/ac6417
  • A. Poro, E. Paki, M. G. Blackford, F. Davoudi, Y. Aladag, S. Zamanpour, S. Sarabi, A. Halavati, N. Aksaker, H. Bagis, J. Rahimi, H. Guilani, A. Akyuz, F. Jahediparizi, O. Doner, Z. Ashrafzadeh, 2022. The Photometric Study of Six W UMa Systems and Investigation of the Mass–Radius Relations for Contact Binary Stars. Publications of the Astronomical Society of the Pacific. DOI: 10.1088/1538-3873/ac71cd


Atila Poro: