Why does the earth support life

The line dividing day and night cuts through South America, with night about to fall on the western half of the continent. Earth is one special planet.

Why does the earth support life

What makes a planet habitable? Using their online toolyou can help NASA in their search for new planets. Astrobiologists estimate that the Milky Way has habitable planets, which fit the following criteria: This just-right distance is called the "habitable zone.

They are good candidates for having a protective atmosphere. The atmosphere holds carbon dioxide and other gases that keep the planet warm and protect its surface from radiation. What about intelligent life? Even today, most Earth life is microbial.

And microbes have been here for at least 3. Given the number of potentially habitable planets within our home galaxy, chances are good that microbial life exists elsewhere. Whether more-complex life forms like plants and insects exist elsewhere is a bigger question.

Multicellular, macroscopic algae and animals came onto the scene about million years ago. The oldest fossils of our species, Homo sapiens, are less thanyears old.

If, like on Earth, intelligent life takes much longer to evolve than microbial life, it might be rare. But some galaxies and solar systems are much older than ours, so maybe other intelligent life has formed; however, it may be long dead.

Finding living intelligent beings is a matter of both space and time. Looking for signs of life past or present Left Evidence that there may have once been liquid water on the surface of mars. Right Fossilized remains of underwater colonies of bacteria, called stromatolytes.

Just as conditions on Earth have changed drastically over time, so have conditions on other planets. When astrobiologists evaluate a planet, they look not just at its current conditions, but for signs that it could have been habitable in the past. Liquid water leaves behind a kind of footprint.

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Mars, for example, has what looks like dry river and lake beds, making astrobiologists wonder if the cold, dry planet could have once been covered with life. If it was, there may be enough remaining liquid water to sustain microbial life deep underground or under the frozen ice caps.

Living things change their environment, leaving behind certain physical and chemical signatures. Even a planet that is lifeless today could have fossil evidence of ancient life forms. Fossils and chemical remnants can tell us a lot about what extinct life might have looked like.Energy from the Sun that makes its way to the Earth’s surface can have trouble finding its way back out to space.

This is because of a natural process called the greenhouse timberdesignmag.comt the greenhouse effect, Earth’s temperature would be below freezing.

ANSWER: Venus can NOT support life as we know it. Living organisms cannot survive on Venus. The planet is toxic to carbon-based life. A thick atmosphere rich with carbon-dioxide envelopes Venus and creates a greenhouse effect. Clouds composed of droplets of sulfuric acid hover over the rocky, ocean-less surface.

Air pressure bears down at a force 90 times that of Earth’s, quickly crushing. no Venus could not support lifeVenus cannot support life.

Why does the earth support life

The question of whether the planet Mars can support life has entranced lay people and scientists for years. New research suggests that dust devils and storms on the Red Planet produce oxidants that would render its surface uninhabitable for life as we know it.

"As a consequence, any nascent life. The atmosphere supports life on Earth by protecting it from dangerous electromagnetic radiation, by creating and controlling weather and climate and by providing the gases that plants and animals need to breathe.

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The atmosphere is composed of the troposphere, the tropopause, the stratosphere, the. Kavan Marambe Physical Science Summer 13’ Why Does Earth Support Life? Research Paper Introduction Earth is where all of us live in.

Earth is the 3rd Planet from the sun, as well as the 5th largest planet in our solar system.

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