In search of another Earth

How many Earth-like planets and Sun-like stars are in our galaxy?

Planets that spend about as much time in orbit as the Earth, and are about the same size as the Earth, seem to appear near every fourth star, according to the latest findings.

The Kepler space telescope, which is no longer working today, searched for Earth-like planets orbiting Sun-like stars in the Milky Way since 2009.

Astronomers observed more than 530,000 stars and more than 2,500 planets.

In determining Earth-like planets, they took into account two characteristics: the size of the planet and the time it takes to orbit its star.

They found that the time of orbit of Earth-like planets was 237 to 500 days, with their size ranging between three-fourths and one-half that of the Earth.

Researchers wanted to better understand the process of planet formation and find those that would provide living conditions.

They were particularly focused on finding biomarkers in their atmospheres, molecules that could indicate that life is on these planets.

»But exploring life on exoplanets presents a difficult challenge that will require a much larger space mission,« says one of the leading researchers, Eric B. Ford.

The interest in Earth-like exoplanets is not new to astronomy. Two years ago, it was discovered that seven Earth-like planets revolve around the tiny star Trappist-1, 39 light-years away.

Points to Consider

1. How long does it take for Earth to circle the Sun?
2. Would our weight be the same on other planets?
3. Why is space research important?

***

The original version of this article was published on September 5th.

English translation courtesy of JL Flanner, Total Slovenia News, an English language website with news from and about Slovenia.