NOV 06, 2020 9:30 AM PST

300 Million Planets in the Milky Way May Be Habitable

WRITTEN BY: Annie Lennon

Researchers have found that there could be at least 300 million habitable worlds in the Milky Way galaxy. This could mean that almost half of the stars similar to our sun may have a habitable planet in their orbit. 

For the study, a team led by Steve Bryson from NASA’s Ames Research Center examined observations by Kepler, which operated between 2009 and 2018, alongside data from the European Space Agency’s Gaia spacecraft, which aims to map a billion stars in the Milky Way. 

The researchers used the data to estimate occurrence rates for rocky planets (planets with diameters between 0.5 and 1.5 times that of Earth) in the habitable zones of stars similar to our sun (defined as having surface temperatures between 8,180 and 10,880 degrees Fahrenheit). 

Most stars that met these requirements were either G dwarfs, the same type of star as our sun, making up 7% of the stars in the Milky Way, or K dwarfs, which are almost twice as common as G dwarfs, although slightly smaller in size. 

In the end, the researchers calculated two occurrence rates- one ‘conservative’ and one ‘optimistic’. In the conservative scenario, they estimated between 0.37 and 0.6 planets in the habitable zone to exist per star. Meanwhile, in an optimistic scenario, they calculated each star to have between 0.58 and 0.88 planets capable of supporting life. 

Of note is that the researchers did not consider red dwarfs, which make up around 75% of the stars in the Milky Way. This comes even though a study from 2013 found that roughly 6% of these stars have an Earth-like planet in the habitable zone, including Proxima b, the nearest such world to our solar system, which orbits the red dwarf Proxima Centauri 4.2 light-years away. 

 

Sources: Space.comScience Alert

About the Author
  • Science writer with keen interests in technology and behavioral biology. Her current focus is on the interplay between these fields to create meaningful interactions, applications and environments.
You May Also Like
SEP 07, 2020
Space & Astronomy
An Unusual Black Hole Merges with Another
SEP 07, 2020
An Unusual Black Hole Merges with Another
A bulky black hole, which may have already been the product of a black hole merger, appears to have tangled with a more ...
SEP 10, 2020
Space & Astronomy
Could There Be Life on Venus?
SEP 10, 2020
Could There Be Life on Venus?
Venus is the hottest planet in our solar system, reaching 465 degrees Celcius- a temperature hot enough to melt lead. Wh ...
SEP 20, 2020
Space & Astronomy
Potential Signs of Life Spotted in the Clouds of Venus
SEP 20, 2020
Potential Signs of Life Spotted in the Clouds of Venus
Scientists were stunned to discover possible signs of life in the atmosphere of Venus. Their initial findings were confi ...
NOV 02, 2020
Space & Astronomy
Never-Found-Before Molecule Detected in Titan's Atmosphere
NOV 02, 2020
Never-Found-Before Molecule Detected in Titan's Atmosphere
Astronomers have detected Cyclopropenylidene (C3H2) on Titan, one of Saturn's 53 confirmed moons. While the molecule ...
NOV 09, 2020
Space & Astronomy
Icy Planet Between Saturn and Uranus Expelled from Solar System
NOV 09, 2020
Icy Planet Between Saturn and Uranus Expelled from Solar System
In mapping the original locations of Saturn and Jupiter in our Solar System, astronomers have found that there was once ...
DEC 28, 2020
Space & Astronomy
China Willing to Share New Moon Samples
DEC 28, 2020
China Willing to Share New Moon Samples
China has recovered the first new moon rock samples in decades, and from a previously unexplored part of the moon. Now w ...
Loading Comments...