NASA's planet-hunting spacecraft, the Transiting Exoplanet Survey Satellite (TESS), discovered a second planet the same size as Earth and suspected that there was water flowing on its surface. The two planets orbit the same star.
TESS was launched in April 2018 and the mission has so far discovered 285 exoplanets and more than 6,000 candidates. One of the most interesting planets is TOI 700 d, which is about the size of Earth and is located in the habitable zone of its star.
So apparently, the planet has a neighboring planet that is quite similar in condition, which is named TOI 700 e. "We saw it and our response was like, 'Is this real?'" Emily Gilbert, astronomer at NASA's Jet Propulsion Laboratory.
Gilbert and colleagues presented the research at the 241st meeting of the American Astronomical Society. TESS finds planets by staring at stars, looking for dips in brightness that would indicate a planet passing between the star and the telescope. From there, astronomers can estimate the size of the planet and its orbital hours.
The newly discovered planet, named TOI 700 e, isn't exactly in the habitable zone, but that definition is constantly changing. Especially after astronomers realized that Venus and Mars may have had water on the surface.
It is estimated that TOI 700 e is about 95% the size of Earth and is likely rocky. Researchers are still continuing to research the planet to find out more about its condition.
"We have other efforts being made to find out more about this planet. There are no results yet, but interesting things will come," said the research team as quoted by us from Space.com.