China searches for ‘Second Earth’ with space telescope project

The space telescope named Earth 2.0 – “Earth version 2.0” of China is expected to be deployed about 1.5 million km from Earth, orbiting the Lagrange 2 point of the Sun – Earth. The project aims to find planets with life and conditions like Earth but located outside the Solar System.

“Earth 2.0” consists of seven telescopes pointing towards the center of the galaxy. With the mission of tracking dim lights and looking for signs of planets as they pass through the space between the parent star and Earth. The telescope will measure the sizes and orbital periods of these planets in search of a “second Earth” version of the hunt for life.

Talking to Space.com, Professor Ge Jian from SAO said that these planetary “candidates” could be tracked with ground-based telescopes to obtain radial velocity measurements from which to determine the radial velocity. determine their mass and density. Others revolve around bright stars that can be further observed spectroscopically to further study the composition of the atmosphere.

The field of view of “Earth 2.0” coincides with the field of view of NASA’s Kepler telescope, but the Earth 2.0 Telescope will have a much larger field of view, helping to observe a wider area and many stars. than. Earth 2.0 telescope covers an area of ​​500 square degrees, 5 times wider than Kepler’s field of view. In which, 6 telescopes 30 cm aperture, together observing 1.2 million stars.

Over the past 9 years, the Kepler telescope has observed more than 500,000 stars and discovered 2,392 planets, but none of them are suitable to be “Earth twins”.

Prof Ge said that the transit method is a statistical game, the more Sun-like stars we look for, the higher our chances of discovering Earth version two.

“If the occurrence rate of Earth 2.0 is 10%, then we need to look for about 2,000 stars similar to the Sun, bright and quiet to follow the movement of Earth 2.0.”Professor Ge said.

The 7th telescope will be a highly sensitive gravitational-gain telescope for surveying wandering planets that do not orbit any stars and exoplanets as distant from their host stars as Neptune and the planet Neptune. small planet like Mars.

The Earth 2.0 telescope mission helps find Earth-sized worlds in orbits similar to our own. However, a planet’s radius and orbit are not indicative of surface conditions and signs of habitability.

Elizabeth Tasker, associate professor at the Japan Aerospace Exploration Agency says: “A new planet could resemble the habitat of Venus or Mars even more alien. To determine if the planet has the same index and vital signs as Earth, scientists science would have to probe the planet’s atmosphere and surface properties as well.”

Proposed Earth 2.0 is part of the space science satellite program of the Chinese Academy of Sciences. It is expected that the final designs will be finalized and evaluated by a group of experts in June. According to the plan, the project will be deployed and launch Long March rocket by the end of 2026.