The so-called exoplanet — or a planet outside our Solar System — has about the same mass as Earth but it circles its star much closer than Earth does the sun.
The hunt for planets like our own has come up with a striking discovery: There’s a planet about the same size as Earth in the nearby Alpha Centauri system.
As Light Years reports, the newly found planet, which orbits a star called Alpha Centauri B, is about 4 light-years, or 23.5 trillion miles, away.
The planet is a rocky world and not gaseous, said Xavier Dumusque of the Geneva Observatory in Switzerland. He and his colleagues published the findings in the journal Nature.
Scientists used an instrument called the High Accuracy Radial velocity Planet Searcher. HARPS, located at the European Southern Observatory’s La Silla Observatory in Chile, which searches for planets outside our solar system using a radial velocity method.
This instrument works in the following way: when a planet orbits a star, the star wobbles back and forth slightly because of the planet’s gravitational force. So, scientists are looking at how fast the star is moving toward or away from Earth.
They measure this through the wavelength of the light from the star, which gets shifted if there’s a planet present (similar to the Doppler effect).
It is thought that the newfound planet is unlikely to harbor life, or at least life as we know it.
It’s located extremely close to its parent star – Earth has a 365-day orbit around our sun, and this other planet orbits its star in only three days. Scientists think that temperatures on the surface could be in the area of 1300 degrees Fahrenheit. The surface is likely to be lava.
There is hope for life in that neighborhood: Small-mass planets like the one orbiting Alpha Centauri B are usually not alone with their sun.
Commenting on the find, University of California astronomer Greg Laughlin said: “This is our back yard, so to find out that planet formation occurred there is just extraordinary.”
As it is known, astronomers have speculated about planets orbiting these suns since the 19th century. But little planets like this are hard to find and instruments have only recently become sensitive enough to detect them.
According to CNN’s ight Years, the next step would be to continue monitoring the shifts in light from the star, looking for other planets.
Time is of the essence, however: As Alpha Centauri B and another star, Alpha Centauri A, move closer to each other, finding any planets in the area will become more difficult. Proxima Centauri, the closest star to Earth besides the sun, may be related to this binary system.
So, when a planet similar to the Earth is discovered, the next step is to start characterizing its atmosphere, looking for elements such as carbon and oxygen that are familiar to life on our own planet.
The discovery gave scientists hope that there are still more exoplanets to discover. Also this discovery might renew dreams of space travel and the discovery of life on planet’s more like our own.