The search for exoplanets – planets orbiting other stars – has been one of the most exciting developments in astronomy and space science in recent years. The first couple exoplanets were found in 1992, and now over 3,400 have been confirmed, with over 5,000 additional candidates. Some of these are smaller rocky worlds similar in size to Earth, bringing scientists close to finding “Earth 2.0” – another planet with water and, perhaps, life. Yesterday, NASA announced another key discovery, bringing us even closer to finding another living world – a star with not just one or two Earth-sized planets orbiting it, but seven. Three of those planets are in the star’s habitable zone, where, depending upon other surface conditions, lakes or oceans of liquid water could exist.
NASA media advisory:
“NASA will hold a news conference at 1 p.m. EST Wednesday, Feb. 22, to present new findings on planets that orbit stars other than our sun, known as exoplanets. The event will air live on NASA Television and the agency’s website.
The Kepler K2 mission has now resumed after a delay of three days, NASA has reported. The Kepler Space Telescope is currently in Campaign 11, during which it is observing a total of 14,250 new targets, including the Galactic Center as well as two of Saturn’s moons, Enceladus and Titan.
Now that we know the closest star system to us has at least one planet, an Earth-mass and potentially habitable one at that, there is one big question a lot of people are asking: Can we go there? Could we send a probe to Proxima Centauri? The answer is… maybe. There have long been ideas and plans for such a mission, but now that at least one planet has been verified there, interest is at an all-time high. It’s doable, but not necessarily easy.
Astronomers today announced one of the most exciting exoplanet discoveries yet: an Earth-mass rocky world orbiting the nearest star to the Sun, Proxima Centauri. There had been hints before of such a world, but nothing was confirmed, until now. The planet, called Proxima b, is not only just slightly more massive than Earth, it orbits within the star’s “habitable zone.” The estimated temperatures of the planet could allow liquid water to exist on its surface. Not only is this planet potentially habitable, depending on other factors, it is also now the closest known exoplanet.
Over the past couple decades, astronomers have been discovering a seemingly endless variety of exoplanets orbiting other stars. Some are rather similar to planets in our own Solar System, while others are more like ones depicted in science fiction, ranging from rocky worlds about the size of Earth and larger, to massive, searing hot planets larger than Jupiter orbiting very close to their stars. Tatooine is another well-known example – the desert planet orbiting two suns in the Star Wars films. Now astronomers have found a similar world, using direct imaging, but which orbits within a system of three stars.