On Tuesday, 25th of November, Professor Lewis Dartnell came to Marlborough to deliver an Astrobiology workshop and the annual Blackett Lecture. He is currently working at the University of Westminster, researching the age-old question, is there anybody out there? He specifically focuses on the search for microbial life on Mars, although his talk covered a wide range of celestial bodies where life could be, or might have been, present.
The workshop was a fascinating, well-tailored event, focusing on the detection of exoplanets, and how astronomers can deduce various things about them, such as mass, orbital radius, and composition, using radial velocity and observing transits. The most interesting conundrums came when observing a system with multiple planets, and how to differentiate the data given by each. The key to many of these problems it seems, is to plot the data on a graph. A light curve graph of a transit can give the planet’s radius, time period and orbital speed, and a graph of redshift and blueshift in the star’s light can give mass and time period, so comparing these values can also give us density, which can help when determining composition. Using spectroscopy as a planet transits can also give us the composition of the atmosphere, when compared to the star’s usual spectrum.
In the main talk, Professor Dartnell covered more of the search for life within our own Solar System, first defining life, then where it might be able to develop. He talked about drilling on Mars, with the Rosalind Franklin rover’s two-metre-long drill. This is a major development, and will reveal so much more than previous drillings down to only 15cm. He also talked about the liquid hydrocarbon seas on Titan, underground liquid water on Europa, and possible fly-throughs of cryovolcano plumes on Enceladus. Finding life in our Solar System would be an incredible achievement, not only because it would be the first extraterrestrial life we’ve seen, but also because it would suggest that life is more common than we thought.
Overall, this was an amazing and incredibly informative event, with something to interest everybody!
Pupil review by Rhea S
