A team of scientists discovered a new Earth-sized exoplanet in a planetary system previously thought to have only two planets. The newly discovered planet is, nevertheless, extremely hot and young. The object, known as HD 63433 d, is also tidally locked on its axis, which means that one side is always facing its Sun-sized star, while the other side is always dark. The planetary system is thought to be 500 million years old, with HD 63433 d exoplanet being the youngest Earth-sized planet nearest to the Earth, at 400 million years. The planetary system known as HD 63433 is approximately ten times younger than our solar system.
The exoplanet is tidally locked
Since the exoplanet is tidally locked, experts believe the scorching temperatures on the dayside could be comparable to other lava worlds in the space. The team behind this discovery even thinks that the planet’s dayside could be a “lava hemisphere.” The system’s star is also a G-type star. Such a star has 0.9 to 1.1 solar masses and an effective temperature ranging from 5,300 to 6,000 K. Our own ‘Sun’ is a G-type star. The scientists, lead by Benjamin Capistrant and Melinda Soares-Furtado, used data from NASA’s TESS (Transiting Exoplanet Survey Satellite) to find a third unknown object in the solar system. Muting signals from the two known exoplanets allowed scientists to discover the presence of a third planet during a ‘transit,’ which occurs when a planet passes in front of its star, obscuring a small portion of the brightness.
This enabled them to see an additional signal: a tiny transit that occurred every 4.2 days. After additional study, they discovered that this was actually a third, smaller planet. The planet is so near to its star that the dayside surface temperature can reach 1,257 Celsius. It’s eight times closer to its star than Mercury is to the Sun. Some experts believe the planet lacks a considerable atmosphere.
