According to Sara Seager, we shouldn’t get excited about signs of life on other planets. However, a genuine discovery of life beyond Earth would be extraordinary. 

Some signs of life on other planets include: 

• Water 
• Carbon dioxide 
• Oxygen or ozone 
• Methane 

NASA’s Nancy Grace Roman Space Telescope and the Wide-Field Infrared Survey Telescope can detect these signs of life. However, the search for life could take decades. 

Here are some examples of signs of life on other planets: 

• K2-18b Researchers detected methane and CO2 in the atmosphere of this planet, which is 120 light years away. The detection of these gases could indicate that the planet has a water ocean. 
• Venus Scientists from Cardiff University detected signs of life on Venus. However, the only habitable portion of Venus is its clouds, which are full of sulfuric acid clouds that could destroy organic molecules. 
• Mars NASA’s Perseverance Rover has been investigating the Red Planet for decades. However, every hint of biology could be explained by an unfamiliar aspect of Mars’s geology or chemistry.

DON’T be excited,” says Sara Seager. She is talking about putative signs of life from observations of the atmospheres of other worlds, and her words are a sobering counterbalance to hyperbolic headlines.

A habitable planet is one that can support life for a long time. Life requires: Liquid water, Energy, Nutrients. 

Carbon dioxide is a good indicator that a planet is suitable for life. However, these are signs that a planet is conducive to life, not that any organisms actually live there. 

The general consensus is that if we find ozone, liquid water, and carbon dioxide simultaneously, it will be a very strong indicator of life.

A planet is habitable if it can support life for a long time. Some signs of a habitable planet include: 

• Distance from its star The planet should be far enough away to avoid the star’s heat and radiation, but not so far away that it’s too cold. 
• Orbit The planet should have a circular orbit so that conditions are constant throughout its year. 
• Temperature The planet should have a temperate temperature and a suitable temperature so that its surface water is liquid. 
• Water The planet should have some water, but not too much. Water vapor in the planet’s atmosphere is a strong indicator that the planet’s temperature is just right for life. 
• Atmosphere The planet should have an atmosphere with strong oxygen levels. It should also have a magnetic field to protect it from harmful solar radiation. 

Other signs of a habitable planet include: 

• Stable rotational axis 
• Plate tectonics 
• Moderate flora and fauna 
• Natural, safe, or biological water 
• Moderate magnetosphere

To determine if there is life on a planet, astronomers can analyze the light from the planet. A method called transit spectroscopy splits the light from the planet’s atmosphere into a rainbow spectrum. This spectrum can reveal the gases and chemicals in the planet’s atmosphere, including those linked to life. 

Astronomers can also look for the following signs of life: 

• Oxygen: Oxygen is abundant in Earth’s atmosphere because of the many plants and organisms that constantly produce it. 
• Biomarkers: These include DNA, RNA, or proteins. 
• Metabolic activity: This can be detected by measuring the production of gases like oxygen or carbon dioxide. 
• Microorganism growth: This can be observed microscopically.

Sara Seager is a Canadian-American astrophysicist and planetary scientist. She is a professor at the Massachusetts Institute of Technology (MIT). She is known for her work on exoplanets, which are planets that orbit stars other than the sun. She is also known for her work on extrasolar planets and their atmospheres

Seager is a professor of: 

• Physics 
• Planetary science 
• Aeronautics and astronautics 

She holds the Class of 1941 Professor Chair at MIT. She is also an Officer of the Order of Canada, one of Canada’s highest honors.

Sara Seager has written eight books, including: 

• The Smallest Lights in the Universe: A Memoir Published in 2020, this memoir explores grief, love, adventure, and heartbreak. It won the Los Angeles Times Book Prize. 
• Is there Life Out There? The Search for Habitable Exoplanets This non-fiction book answers common questions about exoplanets. 
• Exoplanet Atmospheres: Physical Processes Published in 2010 by Princeton University Press. 
• Exoplanets Published in 2010. 

Seager also has two academic books: 

• Exoplanet Atmospheres: Physical Processes 
• Exoplanets

https://bfaddqjkd5ntjx8e4hea-9n804.hop.clickbank.net

Best telescopes on discount on Amazon