When humans began looking into the sky, the first thought that popped the scientific curiosity was are we alone in the universe? In time, we discovered planets around the Sun, separated by billions of kilometers, forming our solar system. Nasa has gone a step beyond that cosmic boundary and confirmed there are more than 5,000 worlds waiting to be explored in deep space.
With the discovery of 65 new planets, Nasa has confirmed the presence of over 5000 such planetary bodies around stars beyond our solar system, marking a new milestone in space exploration. The Nasa exoplanet archive got 65 new candidates to be studied that could harbour compositions that might support the presence of water, microbes, gases on the surface or even life.
“The archive records exoplanet discoveries that appear in peer-reviewed scientific papers, and that have been confirmed using multiple detection methods or by analytical techniques,” Nasa said adding that each one of them is a new world, a brand-new planet.
OVER 5000 NEW WORLDS BEYOND OUR SOLAR SYSTEM
The 5000 exoplanets discovered so far have varied ranges when it comes to their composition and characteristics. These include small, rocky worlds like Earth, gas giants many times larger than Jupiter, and hot-Jupiters in scorchingly close orbits around their stars. There are “super-Earths,” which are possible rocky worlds bigger than our own, and “mini-Neptunes,” smaller versions of our system’s Neptune.
Meanwhile, planets orbiting two stars at once, and planets stubbornly orbiting the collapsed remnants of dead stars have also been discovered in the last three decades. “It’s not just a number. I get excited about everyone because we don’t know anything about them,” said Jessie Christiansen, science lead for the archive and a research scientist with the NASA Exoplanet Science Institute at Caltech.
Astronomers have long said that the Milky Way Galaxy has hundreds of billions of such planets and that’s just one galaxy. An image clicked recently by the James Webb Space Telescope shows thousands of galaxies in a single frame, each rife with the possibility for more such unique unexplored worlds.
HOW DO WE DISCOVER PLANETS?
The discovery of planets is a long, painstaking process that requires years of observations peering into data from ground-based and space-based telescopes. The first planet detected around a Sun-like star, in 1995, turned out to be a hot Jupiter: a gas giant about half the mass of our own Jupiter in an extremely close, four-day orbit around its star. A year on this planet, in other words, lasts only four days.
Finding small, rocky worlds more like our own required the next big leap in exoplanet-hunting technology: the “transit” method. This method is one of the most commonly used methods to spot planets or planet-like candidates. Astronomer William Borucki came up with the idea of attaching extremely sensitive light detectors to a telescope, then launching it into space. The telescope would stare for years at a field of more than 170,000 stars, searching for tiny dips in starlight when a planet crossed a star’s face.
If these dips are constant over a period of time it indicates something coming in the way of the star blocking the starlight confirming the presence of a planetary object.
ARE WE ALONE?
So far, YES.
Astronomers the world over believe that there is a big possibility that we might find something resembling life in deep space in the near future as the number of these planetary candidates grows exponentially. So far, we haven’t been able to study these planets in depth.
“I get a real feeling of satisfaction, and really of awe at what’s out there. None of us expected this enormous variety of planetary systems and stars. It’s just amazing,” says Astronomer William Borucki, principal investigator of the now-retired Kepler mission.
With the advent of science and new telescopes like the James Webb beginning observations, the chances are high that we might find something interesting out there.