We live in a very exciting time: answers to some of the oldest questions humanity has conceived are within our grasp.
One of these is whether #Earth is the only place that harbours #life.
In the last 30 years, the question of whether the Sun is unique in hosting a planetary system has been resoundingly answered: we now know of thousands of #exoplanets orbiting other #stars.
But can we use telescopes to detect whether any of these distant worlds also harbour life?
A promising method is to analyse the gases present in the #atmospheres of these #planets.
Astonishingly, we can identify #molecules present in the atmospheres of exoplanets.
Quantum mechanics causes each atmospheric chemical to have its own distinct barcode-like pattern, which it leaves on the light passing through it.
By collecting starlight that has been filtered through an #exoplanet’s atmosphere, telescopes can see the barcodes of the molecules making up that atmosphere.
To take advantage of this, the planet needs to #transit – pass in front of – the star from our point of view.
#astronomy #astrobiology
https://theconversation.com/how-astronomers-plan-to-detect-the-signatures-of-alien-life-in-the-atmospheres-of-distant-planets-272821