1pm – 6pm – Visitors Centre –University of Exeter at Goonhilly 60
What do we know about space and how can we use it to improve life on Earth?
What are exoplanets and how do we find them? All will become clear as our astrophysicists will demonstrate – using a range of fun and quirky methods that you can get involved in. Which are filled with gas and which are rocky? You’ll be able to work this out for yourself with this hands-on activity.
You can also learn about how we use digital twins for the space sector.
Come and take part in a range of interactive activities that demonstrate our space-related research and how our academics use satellite observation to find out more about the environment on Earth and how it is changing, with the aim of providing solutions to climate change and creating pathways towards net zero.
Our experts are on hand to answer all your questions.
The University of Exeter is a leading research-intensive University with campuses in Cornwall and Devon. Come and meet their experts in the visitor centre between 1-6pm to find out how their space-related research can be used to provide solutions to climate change. Or learn what an exoplanet is and how they can be detected from Earth. Get hands-on with their range of interactive activities that demonstrate the science in a fun and interesting way.
On the UoE side of the stand, we will have:
- TV showing videos about remote sensing, digital twins for the space sector, and Environmental Intelligence
- Water Clarity Demonstration
Simple demonstration on measuring water clarity using a mini-Secchi disk. A Secchi disk is a white disk that is lowered into the water and the depth at which it disappears from sight is proportional to the clarity of the water. It was invented in the 19th century, but is still used routinely today, and used for satellite validation of water transparency products. The demonstration involves a bin 3/4 full of water, some food colouring (to make the water a little opaque) and a mini-Secchi disk (see here Fig 9 of this paper https://www.mdpi.com/1424-8220/19/4/936/htm). Participants take turns doing it, to get the concept, and we can also use the data to look at variability between individuals.
The transit method is the most widely used technique for discovering exoplanets; planets outside of our solar system orbiting stars other than our Sun. Although we cannot actually see most exoplanets (yet), we can detect them by looking for dips in brightness of stars. This happens when the exoplanet goes between us and the star as it is orbiting, blocking out a small portion of the emitted light. In this activity you can see this for yourself. By looking at the `star` in the centre from the correct angle, you too can make by-eye transit measurements as the exoplanet orbits. At the University of Exeter, we use exactly this method with large space telescopes, such as Hubble and soon the James Webb Space Telescope (JWST), to discover and better understand exoplanets and their atmospheres.
Radial Velocity Activity
The radial velocity (RV) method is a method that is used to discover and study exoplanets; planets outside of our solar system orbiting stars other than our Sun. In the same way that stars gravitationally pull on planets, causing them to orbit, planets also gravitationally pull on the star. This means that in-fact both the planet and star are orbiting their common centre-of-mass, meaning that the star appears to wobble back and forth in the sky. In the same way that the siren of an ambulance travelling past you doppler shifts as it is moving toward (higher frequency) and away from you (lower frequency), the light from the star also gets doppler shifted as it orbits. The RV method uses these minute doppler shifts to discover and detect the planets exerting a gravitational pull on their host star.
At the University of Exeter, we are using the radial velocity method as part of the Terra Hunting Experiment to detect an Earth-mass exoplanet in an Earth-like orbit around a Solar-like star. This activity demonstrates how both the planet and the star both orbit their common centre of mass, or barycentre.
Planets orbiting stars other than our Sun, known as exoplanets, are incredibly diverse. This activity shows some of the exoplanets that have been discovered with accurate densities and their sizes to scale. What are they made of? Are they terrestrial and rocky, or a gas giant? See if you can guess.