Designing an interactive educational activity for high contrast imaging using a real coronagraph

The study of exoplanets is one of the most well known topics when it comes to astronomy, and naturally captures people's attention and imagination. However, the methods to find these planets around their host stars and study them may be difficult to understand for the vast majority of the public. Having developed a portable coronagraph demonstration bench, we illustrate how an actual coronagraph works. This optical system is designed to be interactive for the public, which allows a closer and more personal exploration of the device. By adjusting mask locations into the beam of light, the user can experience how to eliminate the direct starlight to reveal a nearby faint planet. We have scripted an interactive demonstration, whose purpose is to engage the public. This activity includes an introduction of exoplanets, their diversity and the search for life, and physical manipulatives including the coronagraph demonstration bench and The Unbelievable Blinder Experiment (TUBE). These manipulatives illustrate the basic optical principles of why it is hard to see a faint source of light (planet) when it comes together with a brighter one (star). In particular, TUBE has proven itself to be very successful in the concept introduction to a general or younger audience, starting with a simpler example before moving to the full demonstration. The full routine aims at increasing awareness and excitement about exoplanets, and showing some of the technical challenges associated with seeing and studying them. The materials and equipment are adaptable to a wide range of audiences from children to undergraduate-level physics students. Beyond the specific scientific contents of the activity, the coronagraph bench offers the public an authentic experience with genuine scientific equipment.