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Since the 20th century, astronomers have been searching for alien life and earth-like planets. This search starts with extra-solar planets or exoplanets and to date, we have come across more than 5000 of them. However, just 50 of them are potentially habitable.
A similar potentially habitable exoplanet has now been found in the Wolf 1069 planetary system by a team of astronomers in Germany. Wolf 1069 is a red dwarf star located in the constellation of Cygnus and is 31 Light Years away from Earth.
What are Dwarf Stars?
Dwarf stars are compact stellar remnants that are no longer stars. They are stars with small size and low luminosity, because of which they are brighter in the infrared region of light rather than the visible region. These stars are more likely to be detected by telescopes of infrared sensitivity. Their color can range from blue to red corresponding to their temperature.
The planet dubbed Wolf 1069 b was discovered in 2023 via radial velocity method. This method for detecting exoplanets relies on the fact that a star does not remain completely stationary when it is orbited by a planet. The star moves, ever so slightly, in a small circle or ellipse, responding to the gravitational tug of its smaller companion.
Why do astronomers search for dwarfs?
Dwarfs are smaller, fainter stars which lead to smaller planets orbiting around them. This means it is a great place to look for rocky, terrestrial planets like Earth. Dwarf stars are so much cooler, if those rocky planets were actually quite close to their star, they could still be in the habitable zone where it is not too hot or too cold. These planets make their detection easier by transiting meaning passing through their star which makes observing them easy.
Wolf 1069 b
According to astronomers Wolf 1069 b orbits its red dwarf star in mere 15.6 days which is a bit of a concern. The exoplanet rests at a distance equivalent to around one-15th of the separation between Earth and our Sun, similar to Mercury’s distance from the Sun. Wolf 1069 b is potentially rocky. The planet is estimated to be about 1.26 the mass of earth and roughly 1.08 the size. Wolf 1069 b is the sixth-closest known Earth-mass planet within a conservatively defined habitable zone.
Wolf 1069 b lies within its star’s habitable zone where it receives approximately 65% of the solar radiance that Earth receives. The surface of the exoplanet is cool which makes it appear orange. The exoplanet is tidally locked to its parent star which means one side is always exposed to daylight while opposite to darkness. This case is similar to our Moon as one face of the moon is visible to us (Earth) because the time period of the Moon’s rotation and revolution is approximately the same.
The team mentioned it is hard to predict the planet’s atmosphere since it does not transit (the planet passes between a star and its observer). Life on the planet like Wolf 1069 b would be impossible as its half side always faces the sun and details of the planet’s atmosphere are yet to be tracked down.
The astronomer group also added, “Wolf 1069 b is nonetheless a very promising target for future three-dimensional climate models to investigate various habitability cases,”
The team’s paper was published online in the journal Astronomy & Astrophysics.