After sending robots to the moon, landing on Mars and building its own space station, China is now monitoring distant solar systems. This month, scientists will release detailed plans for the country’s first mission to detect extraterrestrials.
The mission aims to explore the planets in other parts of the Milky Way outside the Solar System, with the aim of locating the first Earth-like planet orbiting in the habitable zone of a star like the Sun. Astronomers believe that such a planet, called Earth 2.0, would have the perfect conditions for the existence of liquid water – and perhaps life -.
More than 5,000 asteroids have already been detected in the Milky Way, most likely by NASA’s Kepler telescope, which ran out of fuel in 2018 and was in use for 9 years. Some planets were rocky earth-like bodies orbiting small red-dwarfs. Stars, but nothing applies to the definition of Earth 2.0.
With current technology and telescopes, it is very difficult to detect the signal of small, Earth-like planets, whose host stars are a million times heavier and a billion times brighter, says Jesse Christiansen, an astronomer at the NASA Exoplanet Science Institute in California. Technology company based in Pasadena.
A Chinese mission called Earth 2.0 hopes to change that. It will be funded by the Chinese Academy of Sciences and will complete its initial design phase. If the designs are sent to a panel of experts for review in June, the mission team will receive funding to begin developing the satellite. The team plans to launch the spacecraft on the Long March rocket by the end of 2026.
The Earth 2.0 satellite is designed to carry seven telescopes that will monitor the sky for four years. Six telescopes will work together to study the Cygnus-Lyra galaxy, the same area as the Kepler telescope. Astronomer Jian Ji, who led the Earth 2.0 mission at the Shanghai Astronomical Laboratory of the Chinese Academy of Sciences, said, “The Kepler field is a low-hanging fruit because there is so much better data from there.
Telescopes look for outer planets by detecting small changes in the brightness of a star, which indicates that a planet has passed in front of it. Using multiple small telescopes together gives scientists a broader vision than a single, large telescope like Kepler. Earth Telescope’s 6 telescopes observe about 1.2 million stars in 500 square degrees, 5 times wider than Kepler’s view. At the same time, Earth 2.0 can observe fainter and farther stars than NASA’s Transiting Exoplanet Survey Satellite (TESS), which studies bright stars near Earth.
“Our satellite will be 10-15 times more powerful than NASA’s Kepler telescope,” says Gee.
The seventh instrument of the satellite will be the gravitational microlensing telescope to study rogue planets – freely orbiting celestial bodies that do not orbit any star – and even exoplanets far away from a star such as Neptune. The gravitational pull of a planet or star detects changes in starlight when it changes the light of the background star that goes ahead of it. The telescope will target the center of the Milky Way, where a large number of stars are located. If successfully launched, it will be the first gravitational microlensing telescope to operate from space.
“Our satellite will be able to conduct a census that identifies extraterrestrials of different sizes, masses and ages. This work will provide a good set of exoplanet models for future research,” he says.
Doubling the data
NASA launched Kepler in 2009 to find out how common Earth-like planets are in the galaxy. To confirm that an asteroid is similar to Earth, astronomers need to measure the time it takes to orbit its Sun. Such planets must be identical in time to Earth and orbit the Sun once a year. According to Chelsea Huang, an astronomer at the University of Southern Queensland in Toomba, scientists need at least three transits to create an accurate orbital period, which takes about three years of data, and sometimes even data breaks.
But four years after Kepler’s mission, parts of the instrument failed, and the telescope could no longer gaze at a portion of the sky. Huang, who worked as a data simulation consultant with the Earth 2.0 team, says Kepler was keen on finding some Earth-like planets.
With Earth 2.0, astronomers could still hold up to four years of data, coupled with Kepler’s observations, to help confirm which Exoplanets is truly Earth-like. “I’m very excited about the opportunity for Kepler to return to the field,” says Christiansen, who hopes to read Earth’s 2.0 data if it’s available.
Ge hopes to find a dozen Earth 2.0 planets. He says they plan to release the data within a year or two of the collection. “There will be a lot of data, so we need all the hands we can get,” he says. The group already has about 300 scientists and engineers, mostly from China, but Ge hopes that more astronomers worldwide will join. “Earth 2.0 is an opportunity for better international cooperation.”
The European Space Agency is also planning an Exoplanet mission – known as Planetary Transit and Oscillations of Stars (PLATO) – which is scheduled to launch in 2026. There are 26 telescopes in Plato’s design, which means they have a much larger field of view than Earth 2.0. . But the satellite will change its view every two years and observe different parts of the sky.