New observations confirm Earth-like planet orbiting nearest star

Worlds without end: New observations have confirmed the existence of an Earth-sized planet orbiting the nearest star to our Sun, Proxima Centauri, only 4.2 light years away..

The planet, Proxima b, is estimated to have a mass 1.17 of Earth’s, and orbit the star every 11.2 days. Based on that orbit, the planet is also in the star’s habitable zone. Whether there is life there however remains unknown.

Although Proxima b is about 20 times closer to its star than the Earth is to the Sun, it receives comparable energy, so that its surface temperature could mean that water (if there is any) is in liquid form in places and might, therefore, harbour life.

Having said that, although Proxima b is an ideal candidate for biomarker research, there is still a long way to go before we can suggest that life has been able to develop on its surface. In fact, the Proxima star is an active red dwarf that bombards its planet with X rays, receiving about 400 times more than the Earth. “Is there an atmosphere that protects the planet from these deadly rays?” asks Christophe Lovis, a researcher in UNIGE’s Astronomy Department and responsible for ESPRESSO’s scientific performance and data processing. “And if this atmosphere exists, does it contain the chemical elements that promote the development of life (oxygen, for example)? How long have these favourable conditions existed? We’re going to tackle all these questions.

The research data also suggests there might be another planet in orbit around Proxima Centauri, though this conclusion is very preliminary.