An Earth-sized exoplanet, named LTT 1445 Ac, has been discovered just 22 light-years away, making it the closest Earth-sized world to our Solar System. Researchers in the United States identified the exoplanet, which orbits a small red dwarf star and has approximately 1.37 times the mass and 1.07 times the radius of Earth. While the planet is too hot to support life, its resemblance to Earth offers an opportunity to explore the factors influencing the evolution of such planets.
The discovery relied on data collected by the TESS exoplanet-hunting telescope in 2021, presenting challenges in observations that made it difficult to ascertain certain properties of LTT 1445 Ac. Notably, the exoplanet is part of a trinary system, orbiting one of three gravitationally bound stars. Studying exoplanets in systems with multiple stars introduces complexities, as the gravitational influence of stellar companions affects the light emitted by each star.
Understanding the properties of an exoplanet involves two key measurements: transit data and radial velocity data. Transit data detects small dips in starlight when an exoplanet passes between its star and Earth, providing information on the exoplanet’s radius. Radial velocity data measures the gravitational tugs of an exoplanet on its star by recording changes in the starlight’s wavelength, indicating the exoplanet’s mass.
The combination of mass and radius determines the exoplanet’s density, offering insights into its composition. Low density suggests a gaseous atmosphere akin to a gas giant, while higher density implies a rocky composition, similar to Earth, Venus, Mars, or Mercury. This methodology helps scientists classify and understand the nature of exoplanets and their distinct characteristics.
Post Your Comments