Our research projects
Research is loosely organised into projects (established by project leaders, frequently with specific timeframes or goals) and programmes (established by programme coordinators, with ongoing goals and which may have related projects to investigate specific objectives).
Here’s the list of VSS research projects. Find a project that suits your interests, equipment and situation, and contact its project leader to find out about joining in.
BL Tel Project
Project Leader: Peter Williams
Visual observers are invited to participate in monitoring of BL Tel for which ongoing observations are required. BL Tel was the subject of a long-term visual study between 1983 and 2000 with 8 eclipses recorded during that time. Results of those eclipses are summarised in Publications 25 (C99) of the VSS RASNZ (2000). BL Tel is an Algol type system well suited to visual observation and need only be followed during the 3 months centred on the predicted date of mid eclipse.
Eclipsing Binaries – Insight into Stellar Evolution
Coordinator: Tom Richards
“Everybody knows” that wide, visually separated binaries provide an indispensable first step to astrophysics as well as the distance scale ladder. All we need to know is their distance by parallax methods, their orbital period P, and the apparent size of the orbit. True orbit follows, then their masses. Magnitudes at that distance give true luminosities which with their colour gives temperatures, thence their size. There’s no other way of making this first interstellar step.
QZ Carinae
Project Leader: Stan Walker
One of the most difficult observing targets in our galaxy is QZ Carinae, a massive EB system. It comprises four stars arranged in two pairs: an eclipsing secondary pair with a period of 5.99875 days and a non-eclipsing primary pair with a period of 20.74 days. Masses are 16.7 and 28.0, and ~40.0 and ~9.0 respectively. Separation of the two pairs is about 50 AU and the absolute luminosity about –7.5. It’s almost naked eye at 2500 parsecs!
V0454 Carinae spectroscopic and photometric campaign
Campaign Coordinator: Mark Blackford Professional Advisor: Ed Budding
Ed Budding and Roger Butland are currently investigating this relatively bright but neglected eclipsing binary (range 6.96 to 7.16 V Mag, period 0.980417d). They’ve measured radial velocities from high resolution spectra recorded with the HERCULES spectrometer on the 1m McLellan telescope on Mt John and proposed that V0454 Car is probably another quaternary system – not unlike QZ Car, but a bit less massive.
The RV curve of the close binary system (eclipsing pair) is well covered, and they can get a reasonably good picture of it from both its set of spectral lines. However, the third component shows unexpected short-term variations superposed on a much longer-term trend. They think that it is in a binary arrangement with a lower mass companion having a period of order a week or two. However, they don’t have enough information to form a very clear picture at the moment.