About the ALTAIR Group

Altair is a group of amateur astronomers, John Mallett, David Pulley, Ian Sharp and Sebastian von Harrach, whose interest is centred on the detection of circumbinary objects around short period, less than 1 day, binary systems. Our group formed in 2010 as part of an Open University S382 Astrophysics course. A sub-module of the course split us into groups, our group was Altair, to investigate a binary system using the University’s robotic telescope, PIRATE, located in the island of Mallorca, Spain. The Altair group chose the short period binary system TW CrB.

After completing the course, and in late 2010, four of the Altair group decided to continue observing TW CrB and publish our findings in the BAA Journal. We thank Dr Ulrich Kolb of the University’s Astronomy and Physics Department for assisting us in this process. The Altair group comprised of George Faillace, Carl Owen, David Pulley and Derek Smith.

After completing this first study, we were interested in continuing our investigations of eclipsing short period binaries and in particular explore whether claims for the existence of circumbinary planets by others was reliably founded on scientific data. In March 2012 we attended a talk on exoplanets at the Institute of Physics delivered by the Open University’s head of the Astronomy, Professor Andrew Norton. We discussed with him possible future projects and at his suggestion we embarked on a programme observing seven post common envelope sdB binaries, many of which had claims for the presence of circumbinary planets or brown dwarfs.

In the intervening seven years we have been fortunate to have published a number of related papers in the BAA Journal, Astronomy and Astrophysics, Monthly Notices of the Royal Astronomical Society and The Astronomical Journal. These papers are available at Cornell’s University open access arXiv repository: http://arxiv.org. Over this same period the Altair group has changed, welcoming new members Americo Watkins (2014), Sebastian von Harrach (2016), John Mallett (2018) and Ian Sharp (2019). We are all members of the British Astronomical Association (BAA). During this period we have said goodbye to Carl Owen (2014), Derek Smith (2018) and Americo Watkins (2019).

Sadly we record the passing of George Faillace in March of 2020.

Today, our interest has grown to eighteen binary systems and the work of observing and monitoring these fascinating systems continues.

The Altair Group ~ August 2021

A list of published papers by members of the Altair group follows. Please note that links to arXiv have been provided where it is not possible to provide direct access within a Journal's website.

Title Reference and Link
Eclipse time variations and the continued search for companions to short period eclipsing binary systems (2020 J. Br. Astron. Assoc. 130, 6)
An updated model for the circumbinary planets orbiting the sdB binary NY Vir (2019 Astron. Jour. 157, 184)
The quest for stable circumbinary companions to post-common envelope sdB eclipsing binaries Does the observational evidence support their existence? (2018 A&A. 611, A48)
Observing NY Vir and the quest for circumbinary planets (2016 J. Br. Astron. Assoc. 126, 4)
A new and improved ephemeris for the hot subdwarf eclipsing binary SDSS J082053.53+000843.4 (2016 J. Br. Astron. Assoc. 126, 2)
The eclipsing binary HS0705+6700 and the search for circumbinary objects (2015 J. Br. Astron. Assoc. 125, 5)
EL CVn-type binaries - Discovery of 17 helium white dwarf precursors in bright eclipsing binary star systems (2014 MNRAS. 134, 2, 1681)
Investigating the properties of the near contact binary system TW CrB (2013 J. Br. Astron. Assoc. 123, 2)