kepler telescope glimpses population freefloating

Its “year” is just over 11 days and its orbit may be circular or significantly elongated. So what to make of Proxima b? It is at least as massive as Earth, and may be several times more massive.

The variety and tenacity of Earth-bound life encourages astrobiologists to imagine that life can exist not only on Earth-like exoplanets, but also on strange, exotic worlds. Life also requires sufficient time to originate and evolve, but on Earth it has proven resilient to calamities as trivial as a thunderstorm or as traumatic. The habitable zone is a map of where liquid water could exist on the surfaces of rocky, Earth-like planets, hence its status as the first requirement for a planet to be habitable. The limiting factor from an astrophysical perspective is that water must be in its liquid phase. The first two ingredients are very abundant throughout the universe, as is the water molecule. Regardless of how extreme the environment, all life on Earth requires three basic ingredients: energy, nutrients and liquid water. Life on Earth has established itself in a stunning diversity of habitats, including acidic hot springs, the deepest reaches of the oceans, microscopic channels in sea ice, and the deepest levels of Earth’s crust. To evaluate the possibility of life on Proxima b, we must begin with the only habitable planet we know, Earth. Whether Proxima b is a sterile wasteland or teeming with life, we are now embarking on an unprecedented era of discovery, one that may finally provide an answer that age-old question “Are we alone?”. This difference is frustrating, in that it will make our initial interpretations challenging, but also exciting, as it offers the chance to learn how Earth-sized planets evolve in our universe.

If Proxima b is in fact habitable, meaning it possesses liquid water or even inhabited, meaning life is currently present, then it will have traversed a very different evolutionary path than Earth. The discovery of Proxima b has me very excited, but being Earth-sized and in the habitable zone are just the first two requirements for a planet to support life, and the list of requirements is much longer for planets orbiting red dwarfs than for stars like our Sun. My research involves building computer models that simulate how planetary interiors and atmospheres evolve, how stars change with time, and how planetary orbits vary. The possibilities are varied and depend on phenomena usually studied by scientists in fields that are considered distinct, but an integrated perspective - an astrobiological perspective - can provide a realistic assessment of the possibility that life could have arisen and survived on the closest exoplanet.Īs an astrobiologist and astronomer at the University of Washington, and a member of NASA’s Virtual Planetary Lab, I have investigated the habitability of planets orbiting red dwarfs for years. However, we can extrapolate from the worlds of our Solar System, as well as employ theoretical models of galactic, stellar, and planetary evolution, to piece together realistic scenarios for Proxima b’s history. But is Proxima b habitable? Is it inhabited? These questions are impossible to answer at this time because we know so little about the planet. This planet may represent humanity’s best chance to search for life among the stars. The planet is not much bigger than Earth and resides in the “habitable zone” of the Sun’s nearest stellar neighbor. The discovery of Proxima b is the biggest exoplanet discovery since the discovery of exoplanets.

Kepler telescope glimpses population freefloating