Scientists discover 95 new planets orbiting stars outside our solar system

The Kepler spacecraft was launched in 2009 and has discovered more than 5,000 candidate exoplanets over two missions.

Some 95 new exoplanets have been discovered by scientists at the University of Denmark (Z.Bardon/ESO/PA)

Nearly 100 planets orbiting stars outside our solar system have been discovered by scientists.

Researchers at the Technical University of Denmark’s National Space Institute analysed hundreds of potential exoplanets from data provided by the Kepler spacecraft.

Out of 275 candidate planets, scientists confirmed 95 were exoplanets.

The spacecraft, which is on the K2 mission to discover new exoplanets, has uncovered thousands of candidates since it was launched almost a decade ago.

Andrew Mayo, lead author of the study and PhD student, said: “We started out analysing 275 candidates of which 149 were validated as real exoplanets. In turn, 95 of these planets have proved to be new discoveries.”

Artist's cartoon view gives an impression of how common planets are around the stars in the Milky Way — Artist’s cartoon view gives an impression of how common planets are around the stars in the Milky Way (ESA/Hubble/ESO/M. Kornmesser/PA)

It is given a closer look before it is confirmed to be an exoplanet – but the task is not an easy one as scientists must differentiate between signals from a candidate and signals from other spacecraft.

Mr Mayo said: “We found that some of the signals were caused by multiple star systems or noise from the spacecraft.

“But we also detected planets that range from sub Earth-sized to the size of Jupiter and larger.”

His team found a planet on a 10-day orbit around a bright star named HD 212657. The discovery was deemed significant because the bright star enables the planets to be observed from “ground-based observatories”.

The work was published in the Astronomical Journal and researchers from Nasa, UC Berkeley and the University of Tokyo were involved in the study.

The Kepler spacecraft was launched in 2009 and was re-purposed by engineers and astronomers after a mechanical failure in 2013.

This gave way to the ongoing K2 mission to search for exoplanet transits.

Some 3,600 exoplanets have been found since the first one, 51 Pegasi b, was discovered orbiting a Sun-like star in 1995.

They range in size from Earth-like to Jupiter-sized.

Mr Mayo said: “Exoplanets are a very exciting field of space science. As more planets are discovered, astronomers will develop a much better pictures of the nature of exoplanets which in turn will allow us to place our own solar system into a galactic context.”

Upcoming missions will examine the rocky, Earth-sized planets which could support life.