In the search for life on other planets, a few promising leads have just opened up: Astronomers have identified two worlds with Earth-like masses that sit in the habitable zone around a red dwarf star called GJ 1002.
The habitable zone around a star is the sweet spot between a planet that is too hot or too cold to support life. To be in this region, planets would have to orbit their star at a distance where, in theory, there could be liquid water on their surface.
“GJ 1002 is a red dwarf star, barely one-eighth the mass of the Sun,” says astrophysicist Vera Maria Basinger of the Canary Islands Astronomical Institute (IAC) in Spain. “It is a rather cold and dim star. This means that its habitable zone is very close to the star.”
While we’re still a long way from confirming the existence of extraterrestrial life or even running water, GJ 1002b and GJ 1002c so far tick all the boxes — and just 16 light-years from our solar system, they’re close to Earth. They are in the universe, astrologically speaking.
Two space observing instruments — Espresso (Spectrometer for rocky exoplanets and stable spectral observations) and Carmen (Calar Alto’s high-resolution search for exo-Earth M dwarfs with Echelle’s near-infrared and optical spectrometer) — were to be used in tandem to locate the star. and its planets.
Indeed, the weak light emitted by GJ 1002 required instruments of great sensitivity and precision to recognize its signatures. The research team used 139 spectral observations (deep space radiation measurements) taken between 2017 and 2021 to discover the planets.
Until now, we don’t know much about these celestial bodies except where they are. GJ 1002b is closest to its star and takes just over 10 days to complete an orbit; GJ 1002c is farther out, with an orbit of just over 20 days.
The good news is that the relative proximity of GJ 1002b and GJ 1002c means it’s easier to make more detailed observations. The next step will be to assess the atmosphere based on the light it reflects or the heat it emits.
“The future ANDES spectrograph of ESO’s ELT telescope, in which IAC is involved, can study the presence of oxygen in GJ 1002c’s atmosphere.” says astrophysicist Junay González-Hernandez of IAC.
We are now in the total of 5,000 exoplanets – planets outside Earth’s – that have been detected. As telescopes and data processing algorithms improve, we can identify objects that are smaller and farther from Earth.
Thanks to these technological improvements, we are getting closer to being able to measure the chemical signatures of life on those distant planets, even though they are light years away in space.
“Nature seems determined to show us that Earth-like planets are very common,” says astrophysicist Alejandro Suarez Mascareño of IAC. “With those two, we now know of seven in planetary systems fairly close to the sun.”
Research published in Astronomy and astrophysics.