On The Sky at Night in 2022, George Dransfield shared her Antarctic astronomy adventure. She tells us how her research has gone since then
The Sky at Night TV show, past, present and future
The last time I wrote for ‘Inside the Sky at Night’, in the May 2022 issue, I spoke about my then-recent mission to Antarctica. I travelled to Concordia Station as a PhD student to install some software on ASTEP (the Antarctic Search for Transiting ExoPlanets), a 40cm telescope on the Antarctic Plateau. It’s been a good 20 months since I returned home. So how has ASTEP been changing the world ever since?
In the months after I returned to working in normal temperatures – including gaining my doctorate – I was privileged to lead ASTEP’s first planetary discovery paper. The system we discovered was examined as part of the TESS follow-up programme, and is a super-exciting three-planet system with the super-unexciting name of HD 28109. The three planets range from two to four times the size of Earth and all orbit their host star fairly slowly. This is exactly the kind of planetary system that is tailor-made for ASTEP. The telescope’s unique Antarctic location provides a combination of extremely long nights, dry air and low atmospheric pressure that makes it perfect for detecting the infrequent transit events of these planets. Multi-planet systems orbiting Sun-like stars like HD 28109 are always thrilling to discover, as they help us inch ever closer to finding something that resembles our own Solar System. As well as leading our own discoveries, we contributed data to the detection of dozens of new planets led by other groups. We also have some very exciting new discoveries in the pipeline (including some world firsts) due out in 2024 – watch this space!
As I mentioned in my previous column, we need automatic data analysis software for ASTEP as the Antarctic internet connection is unbearably slow. Instead, the annual summer service missions provide an opportunity to bring the previous season’s raw data home. I was given one of two sets of hard drives containing several terabytes of images taken during the preceding three seasons, and tasked with getting them back to the UK. Quite a big responsibility! Fortunately, the data made it home intact.
Aside from our main gig of hunting for new planets beyond the Solar System, a lot can be done with our images as we observe a portion of
