In billions and billions of planets throughout the universe, it's difficult to believe there's not one out there with potential for some kind of life.
Astronomers have long been scouring the cosmos for a habitable planet. Conveniently, it appears that one exoplanet with potential is just a close neighbor of Earth: Proxima Centauri b, which orbits the closest star to the sun, Proxima Centauri.
A Planet That Could Host Life
There are a lot of exoplanets to consider, but Proxima Centauri b stands out for its projected capabilities of holding water.
For the research paper published in the journal Astrobiology, scientists used computer models to show that the exoplanet can sustain broad areas of liquid water. With the presence of water, living organisms could potentially develop in this planet.
"The major message from our simulations is that there's a decent chance that the planet would be habitable," Anthony Del Genio, lead author and a planetary scientist at the NASA Goddard Institute for Space Studies, tells Live Science.
Astronomers have had their eyes set on Proxima Centauri b for years, although data is quite scant on this neighbor. Its parent star, Proxima Centauri, is only about 4.2 light-years away from the sun.
Proxima Centauri b is believed to be at least 1.3 times Earth's mass, and it completes an orbit around its star in 11 days, according to Live Science. Perhaps more significantly, it is located in its system's habitable zone, which is the sweet spot where water would not freeze on its surface.
The exoplanet is believed to be extremely close to Proxima Centauri, though, which means it's tidally locked, with only one side facing the star at all times.
This setup could prove to be tricky for a habitable scenario, as it is unlike Earth's conditions. In a paper published in 2016, scientists suggest that the star-facing side of Proxima Centauri could be scorched in the face of constant, near heat, while the space-facing side could have an ocean that's completely frozen.
However, the newly published paper show simulations where a dynamic, circulating ocean transfers heat from one side of the planet to the other via movement of the ocean and the atmosphere.
"Even though the night side never sees any starlight, there's a band of liquid water that's sustained around the equatorial region," Del Genio explains.
A Trip To Proxima Centauri
Future human colonization of the universe, MIT Technology Review points out, would start with trips to nearby cosmic destinations. Proxima Centauri is a practical choice, as it's quite close to the solar system with a number of exoplanets that have been dubbed as potentially habitable, including Proxima Centauri b.
However, it's not a quick and simple trip, especially with existing state-of-the-art technology, according to the work of Frédéric Marin of the University of Strasbourg and Camille Beluffi of the research company Casc4de.
The trip is to Proxima Centauri, a star 4.2 light-years away. Using the fastest known spacecraft available today — the Parker Solar Probe, which travels at over 700,000 kilometers per hour — the journey will take 6,300 years.
This is many generations in the making, with a pool of individuals who should be able to reproduce on their way to the "nearby" star. A minimum of 98 crew members should be aboard, all carefully selected for genetic diversity.
For now, humankind is not quite ready for such an undertaking.