By Helen Wright, Reporter
Thursday, November 8, 2012
A new super-Earth planet which may be capable of supporting life has been discovered around a nearby star by an international team of astronomers led by the University of Hertfordshire.
The planet, named as HD 40307g, is at least seven times bigger than Earth and exists in the habitable zone of a nearby star - HD 40307 - which is part of a six-planet system.
The system was previously thought to contain three planets in orbits too close to the star making it hot to support liquid water and therefor life as we know it to exist.
The new planets were found after analysising images taken from the HARPS 3.6 metre wide telescope in the Atacama desert in Chile, South America.
Dr Mikko Tuomi, a researcher, said: “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.
“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.”
Of the new planets discovered, the one of greatest interest is HD 40307g which has the outermost orbit from the star.
Its orbit around the host star is a similar distance to Earth’s orbit around our Sun, so it receives a similar amount of energy from the star as the Earth receives from the Sun - increasing the probability of it being habitable.
This is where the presence of liquid water and stable atmospheres to support life is possible and, more importantly, the planet is likely to be rotating on its own axis as it orbits around the star creating a daytime and night-time effect on the planet which would be better at creating an Earth-like environment.
Hugh Jones, University of Hertfordshire, added: “The longer orbit of the new planet means that its climate and atmosphere may be just right to support life.
“Just as Goldilocks liked her porridge to be neither too hot nor too cold but just right, this planet or indeed any moons that it has lie in an orbit comparable to Earth, increasing the probability of it being habitable.”
Mikko Tuomi carried out this work as a member of the European science network RoPACS (Rocky Planets Around Cool Stars) - an initiative with a research focus on the search for planets around cool stars.
RoPACS has pan-European membership and is led from the University of Hertfordshire by Professor Hugh Jones – Professor of Astronomy, said: “Discoveries like this are really exciting, and such systems will be natural targets for the next generation of large telescopes, both on the ground and in space.”