MSU professor, NASA team, discover new planet that could sustain life

Mark Johnson
Lansing State Journal
An illustration of the newly discovered Earth-size planet TOI-700e orbiting within the habitable zone of its star. Its Earth-size sibling, TOI 700d, can be seen in the distance. Joey Rodriguez, an assistant professor in MSU’s Department of Physics and Astronomy, is part of the team of researchers working with NASA’s Transiting Exoplanet Survey Satellite that discovered the planet.

EAST LANSING — After more than a year of extra-stellar detective work, a Michigan State University professor has helped NASA confirm the existence of a new planet about 100 light years away that could be capable of supporting life.

The newly confirmed planet, TOI-700e, is the third discovered in the TOI-700 solar system by Joey Rodriguez, an assistant professor in MSU’s Department of Physics and Astronomy, and a team of researchers working with NASA’s Transiting Exoplanet Survey Satellite, a space-based telescope that observes millions of stars and looks for planets passing in front of the stars. 

The team announced the discovery Tuesday at the American Astronomical Society meeting in Seattle. In 2020, Rodriguez and his team first confirmed the existence of the TOI-700 solar system and at the time confirmed the existence of three planets — TOI-700b, TOI-700c, and TOI-700d. But there was some indication that there could be a fourth planet, Rodriguez said. 

After another year of observation and studying the TOI-700 star, researchers were able to confirm TOI-700e, the solar system’s fourth-known planet. Because of TOI-700e's location within the star’s habitable zone, Rodriguez and his team believe the newly discovered planet could be capable of supporting life. 

“We don’t know a ton about the planet,” Rodriguez said on Friday. “We know how big it is. We know how far away from the star it is. We know how long its year is. It’s at a distance where the energy of the star … that it should be at the temperature for liquid water to exist.”

Liquid water is a crucial ingredient needed to sustain life on a planet, he said, and TOI-700e sits at a distance in proximity to the solar system’s star to where the liquid water could be possible. 

One way scientists can confirm their suspicions that the planet can indeed sustain life is by studying the planet’s atmosphere, pressure and looking for biological signatures, like oxygen or other molecules that could confirm that conditions exist on the planet that would allow for life. 

It’s an issue Rodriguez expects will be debated for decades. Even if a biological signature is identified in the planet’s atmosphere, which is very difficult to determine, some chemical signatures could be explained by non-biological sources, according to the press release. 

“We need to look for the evidence that there’s the right biology on the planet (to conclude that it could sustain life),” Rodriguez said. 

Researchers also suspect that TOI-700d could be capable of sustaining life because it too orbits within the star’s habitable zone. Rodriguez compared the two newly discovered planets to Earth and Venus — TOI-700d sits in a similar proximity to its star as Earth does to the sun, and TOI-700e sits similar to where Venus is on the edge of the habitable zone. 

There are no signs that the solar system is home to any more planets that have yet to be discovered, but Rodriguez didn’t rule out the possibility as researchers continue to study the TOI-700 system. 

“This is one of only a few systems with multiple, small, habitable-zone planets that we know of,” said Emily Gilbert, a postdoctoral fellow at NASA’s Jet Propulsion Laboratory in Southern California, who is leading the project, in a press release. “That makes the TOI-700 system an exciting prospect for additional follow-up.”

Neither humans nor satellites will be traveling anywhere close to the new planet any time soon. The technology needed for a 100-light year trip does not yet exist, Rodriguez said, but that won’t keep him and the team of researchers from continuing to study the solar system and the planets they’ve discovered.

Rodriguez, who has been doing this work for 12 years, hopes there are more planets to find. 

“There’s so much parameter space and places where planets could exist,” he said. “We’ll probably find more things, but they’ll be more difficult to discover.”

Contact Mark Johnson at majohnson2@lsj.com. Follow him on Twitter at @ByMarkJohnson.