Astronomers have discovered 85 possible planets set outside the solar system that could sustain life.

It's believed that the planets are similar in size to Jupiter, Saturn and Neptune, and were discovered using data from NASA’s Transitioning Exoplanet Survey Satellite (TESS).

TESS helps scientists observe dips in the brightness of stars, known as transits, caused by objects passing in front of them.

Often at least three transits need to be seen to discover an exoplanet in this way, to determine how long they take to orbit their star.

However, the new study shows researchers looked at systems that only transit twice, resulting in planets with longer periods of orbit, enabling the discovery of exoplanets at cooler temperatures.

Researchers discover 85 potential new planets

The 85 candidate exoplanets take between 20 and 700 days to orbit their host stars, whereas most exoplanets observed by TESS have orbital periods of 3-10 days.

Bournemouth Echo: Faith Hawthorn and Dr Sam Gill at the Marsh Observatory on the University of Warwick campus.Faith Hawthorn and Dr Sam Gill at the Marsh Observatory on the University of Warwick campus. (Image: PA)

Researchers say that some of the planets are far enough away from their host stars that they could be at the right temperature to sustain life.

The exoplanets still need to be confirmed but the researchers hope this will be achieved with future observations.

Out of the 85 exoplanets, 60 are new discoveries while 25 have been detected in the TESS data by independent research teams using different techniques.

Faith Hawthorn, PhD researcher at the University of Warwick, said: “We ran an initial algorithm searching for transits on a sample of 1.4 million stars.

“After a painstaking vetting process, we whittled this down to just 85 systems that appear to host exoplanets that transit only twice in the dataset.”

Professor Daniel Bayliss, also involved in the research, added: “It’s very exciting to find these planets, and to know that many of them may be in the right temperature zone to sustain life.”

He added: “Encompassing the collaborative spirit of the TESS mission, we have also made our discoveries public so that astronomers across the globe can study these unique exoplanets in more detail. We hope this will drive further research into these fascinating exoplanets.”

Dr Sam Gill, second author of the study, noted: “Detecting exoplanets from just two transits is a clever way to find longer period exoplanets in transit surveys. It allows us to find planets that are much cooler than can be found with traditional transit searches.”

The international collaboration led by Ms Hawthorn at the University of Warwick was published on Wednesday in the Monthly Notices Of The Royal Astronomical Society (MNRAS).