The newly discovered planet, Proxima b, has been found in the Habitable Zone around Proxima Centauri, the closest star to our Sun, meaning it could potentially support life and surface water. Proxima Centauri itself is part of a triple system of stars in the neighbouring Solar System of Alpha Centauri, some 4.2 light years away from Earth (approximately 25.2 trillion miles) and also the target of humankind’s first attempt to travel to another star system, the StarShot project.
Dr Mikko Tuomi, from the Centre for Astrophysical Research at the University of Hertfordshire, said: ‘According to the findings the planet has a rocky surface and is only a fraction more massive than the Earth. It is the closest possible exoplanet to us and may be the closest to support life outside the Solar System.’
The announcement of the new found planet has been a long time in the making. Professor Hugh Jones from the University of Hertfordshire explained: ‘Initial observations of the planet were made more than 15 years ago in March 2000. We first submitted a scientific paper presenting the planet’s existence back in February 2013. My colleague Dr Mikko Tuomi had discovered the planet's fingerprints in archived data taken before 2009, but we didn’t have enough evidence to conclusively support such a major discovery. Dr Guillem Anglada-Escudé then joined the University of Hertfordshire team and coordinated major observing campaigns. These gave us enough observations to unequivocally confirm the planetary signal with several independent datasets.’
A crucial aspect was to be sure the signal was due to a planet. This was established by Dr John Barnes, also formerly a researcher at the University of Hertfordshire now based at the Open University and Dr James Jenkins, a former University of Hertfordshire PhD student, now at the University of Chile. Dr Barnes said: ‘Once we had established that the wobble wasn’t caused by star spots, we knew that that there must be a planet orbiting within a zone where water could exist.’
The final campaign involved the University of Hertfordshire working as part of the ESO project called The Pale Red Dot, a coordinated international effort involving more than 30 scientists from eight different countries across three continents. As a result, the University of Hertfordshire’s Bayfordbury Observatory now has a major monitoring programme aimed at other nearby stars like Proxima.
Speaking on the possibility of life being found on the planet, Dr Tuomi, said: ‘If Proxima b has an atmosphere and if there is water there, and these are big ‘ifs’, it is intriguing to think that the simple ingredients - water, carbon dioxide, and rock - that are needed for the formation of biochemical cycles that we call life, could all be present and interacting on the planet’s surface. But we do not really know. We need to study this system a lot more over the coming decades in order to be able to start answering such questions. However, it is a great place to start looking for life outside the Solar System and it is a very exciting discovery.’
Dr Guillem Anglada-Escudé, now based at Queen Mary, University of London added: ‘Many exoplanets have been found and many more will be found, but searching for the closest potential Earth-analogue and succeeding has been the experience of a lifetime for all of us. Many people’s stories and efforts have converged on this discovery. The result is also a tribute to all of them. The search for life on Proxima b comes next.’
Universities, Science, Research and Innovation Minster, Jo Johnson, said: 'The discovery of Proxima b adds to what has already been a momentous year for UK space research, and our global leadership in science and innovation. It is yet another prime example of the pioneering and collaborative work of the scientists and researchers across the UK, and government’s commitment to increase our science budget will help support them to make even more exciting discoveries.'
Business and Energy Secretary, Greg Clark, said: 'Following the record-breaking experiments conducted by Tim Peake on board the International Space Station, the discovery of Proxima b is another significant step forward for our understanding and knowledge of space. And this latest development is testament to the hard work and scientific endeavour of UK institutions who are leading the charge and making discoveries that could change lives and inspire millions around the world.'