NASA DISCOVERS NEW SOLAR SYSTEM

Key observations were made by the Trappist robotic telescope at La Silla, Chile which gives the system its name.  Three planets – classified as TRAPPIST-1e, f and g – orbit in the “habitable” or so-called “Goldilocks” zone where temperatures are suited to surface oceans of liquid water.

The star at the center of the solar system has a temperature of 2550K and is at least 500 million years old. In comparison, the Sun is about 4.6 billion years old  and has a temperature of 5778K. The six inner planets lie in a temperate zone where surface temperatures range from zero to 100C.

Nasa’s Hubble Space Telescope is already being used to search for atmospheres around the planets. Future telescopes, including the proposed European Extremely Large Telescope and the James Webb Space Telescope, may be powerful enough to detect markers of life, such as oxygen, in the atmospheres of exoplanets.

Prof Sara Seager, an expert in planetary science and physics at the Massachusetts Institute of Technology, said: “In this planetary system, Goldilocks has many sisters.

We have made a giant accelerated leap forward in the search for habitable worlds and life in other worlds,” she said. The Spitzer telescope, which uses infrared technology, was able to track how fast each of the planets crossed TRAPPIST-1 and completed an orbit.

From this the research team calculated how far the planets were from their star, and therefore how likely they are to be habitable. They were assisted by astronomers from Liverpool John Moores University, operating a ground-based telescope in the Canary Islands.

British astronomer Dr Chris Copperwheat, from Liverpool John Moores University, who co-led the international team said: “As a robotic telescope and the largest in the world, the Liverpool telescope is very sensitive to the small, less than 1 per cent, dips in brightness through which the planets are discovered.”

The new planets are very close to each other and Dr Gillon said a person standing on the surface of one would have a view of its neighbours, similar to seeing the Moon from Earth.

The first exoplanet was confirmed to have been discovered in 1992, since when a total of 3,577 have been found. Of these, less than a dozen are thought to be well suited to supporting life, and Nasa said only three previously known exoplanets were as ideal as those in the new solar system.

Around a fifth of Sun-like stars are thought to have an Earth-sized planet in their habitable zones. Astronomers estimate there could be as many as 40 billion potentially habitable worlds in our galaxy, the Milky Way. Prof Zurbuchen said that now was a “gold-rush phase” in the search for these exoplanets.

“This is going forward at a rapid pace not just because of the telescopes there, but the telescopes we are launching soon,” he said.

Dr Copperwheat, added: “The discovery of multiple rocky planets with surface temperatures which allow for liquid water make this amazing system an exciting future target in the search for life.”

A robotic telescope operated by Liverpool John Moores University played a major role in the discovery reported in the journal Nature.

It was one of a number of ground-based instruments that supported observations made by American space agency Nasa’s orbiting Spitzer telescope.

The Liverpool telescope helped detect the planets as they passed in front of their star.

The planets were found using the “transit” method that looks for tiny amounts of dimming caused by a world blocking light from its star.

The Liverpool Telescope is located on La Palma in the Canary Islands.

Astronomer  Royal Sir Martin Rees thinks he discovery of these new worlds is just the start. There are many more life-supporting planets out there waiting to be discovered he says…