NASA astronomers announced the discovery of the closest rocky planet beyond the solar system through the use of the Spitzer Space Telescope. The new planet is believed to be larger than the planet Earth and could provide researchers with a treasure trove of scientific data.
The America space agency said that the newly discovered exoplanet, named HD 219134b, is located around 21 light-years away from Earth. It orbits its star too closely to be able to sustain any form of life.
Despite not being directly visible even through the use of telescopes, the rocky planet's star can be seen to the naked eye during dark evening skies in the constellation of Cassiopeia, close to the North Star.
The HD 219134b is considered to be the nearest planet to Earth outside the solar system to ever be observed crossing in front of its own star, also known as transiting. This makes the exoplanet an ideal subject for extensive scientific research.
Spitzer mission scientist Michael Werner at the Jet Propulsion Laboratory (JPL) in California explained that such transiting exoplanets are vital to scientists because they can be studied extensively. He said that the HD 219134b planet will be one of the most researched exoplanets in the coming decades.
The HD 219134b exoplanet was first discovered by the Galileo National Telescope's HARPS-North instrument located in the Canary Islands. It has been the subject of a study that is set to be published in the Astronomy & Astrophysics journal.
Ati Motalebi, a researcher at Switzerland's Geneva Observatory and co-author of the study, said that the new exoplanet is a suitable subject for research for the James Webb Space Telescope in 2018.
Motalebi said that the Webb and other future massive, ground-based facilities will allow researchers to study the planet in better detail.
The Earth's relative orientation makes it difficult for scientists to observe exoplanets transiting their stars. When it reaches a more suitable orientation, the exoplanet's orbit sets it between the Earth and its own star, considerably dimming the light from it. This dimming of the star's light is what allows observatories, such as the Spitzer, to identify the planet's size and provide data on its composition.
Lars A. Buchhave, an astronomer at Massachusetts Harvard-Smithsonian Center for Astrophysics and co-author of the study, said that compared to other exoplanets that are found hundreds of light-years away, the HD 219134b is relatively close to the Earth.
Spitzer scientists said that the HD 219134b exoplanet is approximately 1.6 times larger than the Earth. By combining the planet's mass and its size, the researchers found that its density is 3.5 ounces per cubic inch, confirming that it is a rocky planet.
