What do we need to find if we want to discover another Earth? If an exoplanet is too far away to directly look for water or certain biological signatures even with the most powerful telescopes, chances are it’s habitable. What else could it tell us about carbon dioxide? The answer could be carbon dioxide.
An international research team led by Amaury Triaud and Julien de Wit now suggests that CO does not exist.2 In a planet’s atmosphere, the possibility of liquid water on its surface may increase.Earth’s own atmosphere CO is depleted2. This is unlike Mars or Venus, which are dry planets with high concentrations of carbon dioxide.2 Our Earth’s oceans take in huge amounts of carbon dioxide from the atmosphere as gases in the atmosphere dissolve in water. C.O.2 The lack of an exoplanet’s atmosphere could mean the same thing.
Another molecule could be a sign of ozone, a habitable planet. Many organisms on Earth (particularly plants) breathe carbon dioxide and release oxygen. This oxygen reacts with sunlight and becomes O.3, or ozone, is easier to detect than oxygen in the atmosphere. The presence of ozone and the absence of carbon dioxide could mean a planet that is habitable and even habitable.
Will someone or something be there?
There is a difference between a planet orbiting within what is considered the habitable zone and its actual habitability. The researchers define habitability as “a planet’s ability to retain large amounts of surface liquid water.” study Recently published in Nature Astronomy.
There are various hypothetical ways to prove that water actually exists. The problem is that most existing telescopes, no matter how powerful, can’t do it all. Spotting liquid water from light years away isn’t as easy as seeing the glow of a lake, but it’s possible at close ranges like within our solar system. (When sunlight reflects off surface liquid, you see what scientists call a “glow.” This is how the lakes and oceans on Saturn’s moon Titan were discovered.)
In addition to water, there are several other factors that determine livability. In addition to atmospheric properties, these include (but are not limited to) the planet’s orbit, plate tectonics, magnetic field, and how the planet is influenced by its star.
When less is more
Tryaud, de Wit, and their team argue that it’s worth trying to identify potentially habitable planets in star systems similar to ours. If you have a system containing multiple terrestrial planets that are similar in size and have atmospheres, compare the carbon dioxide content of their atmospheres and find that one or more planets have a significant deficiency compared to the others. You can check if.
While CO2 The scarcity doesn’t guarantee the presence of liquid water on the surface, but it should give scientists a reason to take a closer look at the planet in question. You don’t have to look far from Earth to see why this makes sense. Not only is most of the carbon dioxide in Earth’s atmosphere depleted by the oceans, but plate tectonics also causes carbon dioxide to be buried in the Earth’s crust.The amount of carbon dioxide in the early Earth’s atmosphere that ended up trapped in rocks is about the same as the amount of carbon dioxide2 throughout Venus’ atmosphere.
Looking for this deficiency also has other benefits. Because it is a particularly strong absorber of infrared radiation, CO;2 It’s fairly easy to detect. Telescopes that currently exist, such as NASA’s James Webb Telescope and ESO’s Very Large Telescope, as well as his ESO’s upcoming Very Large Telescope, are equipped with infrared vision to easily search for CO.2 signature.
So what happens if we find a planet that exhibits CO deficiency?2 Does ozone exist? Researchers believe that the combination of both could mean, at least hypothetically, a habitable planet, rather than just a small number of microbial life forms.
‘Life on Earth shapes the planet’, says research team Said In the same study. “Life forming planets is what astronomers are really looking for.”
Natural Astronomy, 2023. DOI: 10.1038/s41550-023-02157-9