According to astronomers, the new "super-Earth" is called HD 40307g and is located in what is believed to be a habitable "Goldilocks" zone, reported Yahoo! News
The discovery of HD 40307 g was made by a team of international astronomers, led by Mikko Tuomi, University of Hertfordshire, and Guillem Anglada-Escude, University of Goettingen.
Originally the six-planet system of dwarf star HD 40307 was only believed to contain three planets, however "by avoiding fake signals caused by stellar activity, the researchers have identified three new super-Earth planet candidates also in orbit," reported Astrobiology Magazine
“We pioneered new data analysis techniques including the use of the wavelength as a filter to reduce the influence of activity on the signal from this star," said Tuomi. "This significantly increased our sensitivity and enabled us to reveal three new super-Earth planets around the star known as HD 40307, making it into a six-planet system.”
HD 40307 g is said to be
the sixth planet from its sun and orbits 55.8 million miles (90 million kilometers) from the star; the planet's year length is 197.8 days.
The new exoplanet is described as being about seven times larger than Earth and rotating on its own axis during orbit, creating day/night effects. HD 40307 g is located 42 light-years away from Earth, which means it is close enough where researchers may one day be able to collect direct images as technology progresses and newer telescopes are built.
Space.com interviewed Tuomi via email and he said that there is a 50/50 chance that HD 40307 g would be a rocky planet like Earth, stating, "But the truth at the moment is that we simply do not know whether the planet is a large Earth or a small, warm Neptune without a solid surface."
Over time scientists have found a few planets considered to be in "Goldilocks" zones, such as Gliese 581 g
, which is rated as the exoplanet most likely to harbor life forms. Gliese 581 g was discovered in Sept. 2010.
“The star HD 40307, is a perfectly quiet old dwarf star, so there is no reason why such a planet could not sustain an Earth-like climate," said Angla-Escude.