Father and son amateur astronomers discover two gaseous exoplanets

Cesar Rubio and his seven-year-old son Miguel like talking about stars at night, the father says that he tries to nurture that curiosity in his son. By day, Rubio is a machinist from California who makes parts for mining and power generation equipment. The father and son team has now helped scientists discover planets.

Cesar Rubio is one of the thousands of volunteers who participate in the Planet Hunters TESS citizen science project that searches for evidence of exoplanets in data gathered by the TESS mission. The project has more than 29,000 participants worldwide and has announced the discovery of two new exoplanets listing Rubio and more than a dozen other citizen scientists as co-authors.

The newly discovered planets orbit a star called HD 152843 that is about 352 light-years away from Earth. The star the worlds orbit are about the same mass as the Sun but are about 1.5 times larger and somewhat brighter than our star. Planet b is approximately the size of Neptune, making it about 3.4 times larger than Earth. It completes an entire orbit around its host star in approximately 12 days.

Planet c is the outer planet, and it's about 5.8 times larger than Earth, placing it into a "sub- Saturn" category. It orbits the host star at a rate of between 19 and 35 days. If both of these planets were placed inside our solar system, they would be within the orbit of Mercury which takes about 88 days to circle the sun.

TESS is the Transiting Exoplanet Survey Satellite launched in 2018. The team has used data from the observatory to identify more than 100 exoplanets and 2600 candidates awaiting confirmation. Volunteers on the TESS project look at graphs showing the brightness of different stars over time. They note which of the plots show a brief decrease in brightness of the star and then an upward swing to the original level. That rise and fall in brightness can happen when a planet crosses the star's face, known as a transit.