Scientists have discovered an Earth-sized exoplanet, LTT 1445Ac (shown as the black dot in front of the star in the picture), only 22 light-years away from Earth. This is an artist’s rendering. (NASA, ESA)
[The Epoch Times, November 20, 2023](Epoch Times reporter Chen Juncun reported) Scientists have discovered an Earth-sized exoplanet with a diameter 1.07 times that of the Earth. This planet is only 22 light-years away from Earth and is the closest exoplanet known to be Earth-sized. But the planet’s surface temperature is too high for human survival.
The National Aeronautics and Space Administration (NASA) pointed out on November 16 that the agency’s Transiting Exoplanet Survey Satellite discovered a planet named LTT 1445Ac in 2022, but the satellite’s optical analysis It’s not fast enough to determine what the planet’s orbital plane looks like relative to its parent star. This may result in the planet’s diameter not being correctly known.
Fortunately, the observation capabilities of NASA’s Hubble Space Telescope can make up for the shortcomings. Scientists used the telescope to measure the diameter of LTT 1445Ac.
Observations from the telescope showed that LTT 1445Ac made a normal transit, completely crossing its parent star. It’s a rocky planet, just like Earth. Its diameter is 1.07 times that of Earth, which is about the same as Earth, and its surface gravity may also be similar to Earth’s.
However, the surface temperature of LTT 1445Ac is as high as about 260 degrees Celsius. For currently known life, such temperatures are too high to survive.
LTT 1445Ac’s parent star is called LTT 1445A, and this star has two other planets orbiting it, both of which are larger than LTT 1445Ac.
LTT 1445A is one of a three-star system consisting of three red dwarf stars. This three-star system is located in the constellation Eridanus, 22 light-years from Earth. The other two red dwarfs are LTT 1445B and LTT 1445C, which are about 4.7 billion kilometers away from LTT 1445A.
Observations by the Hubble Space Telescope also found that all stars and planets in this three-star system are on the same plane.
Emily Pass, an astrophysicist at the Harvard-Smithsonian Center for Astrophysics in Massachusetts, said transiting planets excite scientists because they can detect them through Spectroscopic analyzes using the James Webb Space Telescope or James Webb Space Telescope were used to characterize the atmospheres of these planets.
“Our measurement is important because it tells us that this may be a very nearby terrestrial planet,” Paz said. “We look forward to follow-up observations that will give us a better understanding of planets around other stars.” Diversity.”
Laura Kreidberg, a scientist at the Max Planck Institute for Astronomy in Germany who was not involved in the study, added that the Hubble Space Telescope still plays a key role in characterizing the atmospheres of planets. character of.
Claydberg said there are a handful of Earth-like planets like LTT 1445Ac that scientists can learn about the composition of their atmospheres. In astronomical terms, LTT 1445Ac, 22 light-years away and right next door to Earth, is one of the best planets for studying atmospheric properties.
Editor in charge: Ye Ziwei#
