In the search for life on other planets, a couple of promising leads have just opened up: astronomers have identified two worlds with masses similar to Earth, located 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 being too hot or too cold to support life. To be in this zone, the planets must be orbiting their star at a distance where, theoretically, there could be liquid water on their surface.
“GJ 1002 is a red dwarf star, with just one eighth the mass of the Sun”, says astrophysicist Vera Maria Passenger of the Instituto de Astrofísica de Canarias (IAC) in Spain. “It is a rather cool and faint star. This means that its habitable zone is very close to the star.”
While we’re still a long way from confirming extraterrestrial life or even running water, GJ 1002b and GJ 1002c are ticking all the right boxes so far, and just 16 light-years away from our Solar System, they’re close to where we are in the Universe, astronomically speaking.
Two space observation instruments: ESPRESSO (Echelle Spectrograph for Rocky Exoplanets and Stable Spectroscopic Observations) and CARMEN IS (Calar Alto High-Resolution Search for M Dwarfs with Exo-Earths with Near-Infrared and Optical Echelle Spectrographs): Had to be used in tandem to detect the star and its planets.
This is because the faint light emanating from GJ 1002 requires highly sensitive and precise instruments to recognize their signatures. The research team used 139 spectroscopic observations (deep space radiation measurements) taken between 2017 and 2021 to detect the planets.
So far, we don’t know much about these celestial bodies, except where they are located. GJ 1002b is the closest to its star and takes just over 10 days to complete one orbit; GJ 1002c is further out, with an orbit of just over 20 days.
The good news is that the relatively close proximity of GJ 1002b and GJ 1002c means that more detailed observations are easier to make. The next step will be to evaluate your atmospheres based on the light they reflect or the heat they emit.
“The future ANDES spectrograph for the ESO ELT telescope, in which the IAC participates, could study the presence of oxygen in the atmosphere of GJ 1002c”, says astrophysicist Jonay I. González Hernández of the IAC.
We now have a total of 5,000 exoplanets, planets outside our Earth, that have been observed. As telescopes and data processing algorithms improve, we can detect 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 these distant planets, even though they are light years away through space.
“Nature seems hell-bent on showing us that Earth-like planets are very common.” says astrophysicist Alejandro Suárez Mascareno of the IAC. “With these two, we now know of seven in planetary systems very close to the Sun.”
The research has been published in Astronomy and Astrophysics.
