NASA Discovers Planet In Habitable Zone; How ‘Super-Earth’ Compare With Our Earth? - India Bytes

This artist’s concept contrasts our familiar Earth with the exceptionally strange planet known as 55 Cancri e. While it is only about twice the size of the Earth, NASA's Spitzer Space Telescope has gathered surprising new details about this supersized and superheated world. Astronomers first discovered 55 Cancri e in 2004, and continued investigation of the exoplanet has shown it to be a truly bizarre place. The world revolves around its sun-like star in the shortest time period of all known exoplanets – just 17 hours and 40 minutes. (In other words, a year on 55 Cancri e lasts less than 18 hours.) The exoplanet orbits about 26 times closer to its star than Mercury, the most Sun-kissed planet in our solar system. Such proximity means that 55 Cancri e's surface roasts at a minimum of 3,200 degrees Fahrenheit (1,760 degrees Celsius). The new observations with Spitzer reveal 55 Cancri e to have a mass 7.8 times and a radius just over twice that of Earth. Those properties place 55 Cancri e in the "super-Earth" class of exoplanets, a few dozen of which have been found. However, what makes this world so remarkable is the resulting low density derived from these measurements. The Spitzer results suggest that about a fifth of the planet's mass must be made of light elements and compounds, including water. In the intense heat of 55 Cancri e's terribly close sun, those light materials would exist in a "supercritical" state, between that of a liquid and a gas, and might sizzle out of the planet's surface. Only a handful of known super-Earths, however, cross the face of their stars as viewed from our vantage point in the cosmos. At just 40 light years away, 55 Cancri e stands as the smallest transiting super-Earth in our stellar neighborhood. In fact, 55 Cancri is so bright and close that it can be seen with the naked eye on a clear, dark night.

New Delhi: The National Aeronautics and Space Administration (NASA) has discovered a planet that can potentially support life, located a not-too-distant (by astronomical standards) 137 light-years away.

“A ‘super Earth’ ripe for further investigation orbits a small, reddish star that is, by astronomical standards, fairly close to us — only 137 light-years away. The same system also might harbour a second, Earth-sized planet,” the American space agency said in a press release.

Dubbed TOI-715 b, the planet is around one-and-a-half times as wide as Earth, and completes a full orbit (a year) in just 19 days.

Its orbit is within the “conservative” habitable zone around the parent star, possibly indicating that it may form liquid water on its surface, according to NASA.

NASA added that several other factors will have to fall in place for surface water to be present, especially having a suitable atmosphere.

“But the conservative habitable zone — a narrower and potentially more robust definition than the broader ‘optimistic’ habitable zone — puts it in prime position, at least by the rough measurements made so far. The smaller planet could be only slightly larger than Earth, and also might dwell just inside the conservative habitable zone,” NASA stated.

“Much will depend on the planet’s other properties, including how massive it is and whether it can be classed as a ‘water world’ – making its atmosphere, if present, more prominent and far less difficult to detect than that of a more massive, denser and drier world, likely to hold its lower-profile atmosphere closer to the surface,” NASA said.