The closest exoplanet similar to Earth has been found – only 22 light years away
Дата: 19.11.2023 05:10
A group of scientists from the United States has confirmed that just 22 light years away there is an exoplanet that closely resembles our Earth. This is the closest Earth-like exoplanet in the entire history of observations, which makes it possible to study the diversity of planets similar to our Earth.
The planet LTT 1445 Ac was discovered by the TESS telescope in 2021. It was discovered by the transit method, as an object passing in front of its star and reducing its brightness. But at that time, observing the exoplanet was difficult because it was orbiting a dwarf star in a triple system. The other two stars in the system influenced the radial velocity and brightness of the third, around which the coveted planet revolved.
To more accurately determine the transit parameters, the researchers connected the Hubble Space Telescope to observe LTT 1445 Ac. With its help, it was possible to determine with the highest accuracy the characteristics of the event, namely the orbital period of the exoplanet, how it passes across the disk of the star and its effect on the radial velocity of the host star. Knowing this information, scientists easily calculated the radius and mass of the exoplanet. The exoplanet LTT 1445 Ac turned out to be approximately 1.37 times heavier than the Earth, and its radius was only 1.07 times the radius of our planet.
The calculated density of the exoplanet LTT 1445 Ac turned out to be 5.9 g/cm3. The density of the Earth is 5.51 g/cm3. It is not difficult to understand that the composition and structure of the exoplanet are very close to those of Earth. What’s sad is that there is no biological life known to us on Earth there. The orbital period of rotation of the world LTT 1445 Ac is only 3.12 days. Even taking into account the fact that the home star of this planet is a dim red dwarf much fainter than our Sun, the temperature on the surface of LTT 1445 Ac reaches 260 °C. Theoretically, the life we know can be there in the twilight zone on the border of light and shadow, if this world does not rotate around its axis. This is a common occurrence at such a close location to the star.
The location of the exoplanet LTT 1445 Ac, which is quite close to us, opens up the horizon of possibilities for studying Earth-sized planets. Its passage across the star’s disk, for example, will make it possible to determine the chemical composition of the atmosphere by analyzing the absorption of lines in the star’s spectrum. The James Webb Telescope can do this. For such research in the future, new telescopes are being prepared that will specifically study the worlds closest to us with the greatest meticulousness.