2019 – Posted in: Daily News

FINGERPRINT OF EARTH’S ATMOSPHERE

For: Mains

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Astronomers at Canada’s McGill University have made a “fingerprint” for the Earth.

These could be used to identify a potentially life-sustaining planet beyond the solar system.
With the data and observations collected by SCISAT Satellite, researchers have constructed a transit spectrum of Earth – detail on the fingerprint-like unique composition of our planet’s atmosphere.

It is a Canadian satellite designed to make observations of the Earth’s atmosphere.
It was launched on August 12, 2003.
The satellite helps scientists to improve their understanding of the depletion of the ozone layer by looking at particles in the atmosphere as sunlight passes through them.
With its help, astronomers can tell what molecules are found in a planet’s atmosphere by observing the changes in starlight as it shines through the atmosphere.

For making this observation, the satellite’s instruments must wait for a planet to pass over the star.
If the telescopes are sensitive enough, astronomers can potentially identify chemicals in such planets like carbon dioxide, oxygen, or water vapour which are molecules that improve the chances that a planet is habitable, or even inhabited.

The findings can help scientists determine the kind of signals called ‘biosignatures’ that astronomers need to look out for in order to find Earth-like planets outside our solar system.
The fingerprint includes the simultaneous occurrence of both ozone and methane, which happens only when there is an organic source of these compounds on the planet.