Potentially Habitable Earth-Sized World Discovered Just 40 Light-Years Away

A world that bears more than a passing similarity to Earth has just been discovered orbiting a star just 40 light-years from the Solar System.

This exoplanet has a very similar radius to our home planet, suggesting a similar rocky composition. Tantalizingly, Gliese-12b, as the exoplanet is named, is at a distance from its host star that could be habitable to life as we know it.

"In my opinion, this planet will give us the clearest answer yet for any potentially habitable planet as to whether it could support habitable conditions," astrophysicist Shishir Dholakia of the University of Southern Queensland in Australia tells ScienceAlert.

"Its host star is inactive, it's extremely nearby and therefore very characterizable."

What we don't yet know is whether Gliese-12b has an atmosphere. That's the factor that could make a huge difference to whether the world is hospitable to life like Earth, or a scorching hell planet like Venus.

"Gliese-12b represents one of the best targets to study whether Earth-size planets orbiting cool stars can retain their atmospheres, a crucial step to advance our understanding of habitability on planets across our galaxy," Dholakia explains.

Over 5,600 planets outside the Solar System, or exoplanets, have been discovered to date, but we're yet to find an Earth 2.0. Most of the worlds we find are larger.

That's not to say that we've not found those with similar sizes and masses to Earth. We've found quite a few, but finding Earth-sized exoplanets that meet the conditions for habitability is a little more difficult.

One of those conditions is that the exoplanet needs to be within a specific distance range from the star, known as the habitable or Goldilocks zone. This is defined by the temperature inflicted on the exoplanet by the star. The exoplanet needs to be close enough for any water on the surface to be liquid, not frozen; but not so close that any water would evaporate clean away.

potentially habitable earth-sized world discovered just 40 light-years away

An artist's impression of the Gliese-12 system, with the exoplanet retaining a thin atmosphere. (NASA/JPL-Caltech/R. Hurt, Caltech-IPAC)

In the Solar System,

potentially habitable earth-sized world discovered just 40 light-years away
. Venus is a bit too close to the Sun. Mars is right at the outer limits, and proof that just sitting in the habitable zone doesn't guarantee habitable conditions – but it's a starting point for identifying worlds that we should examine more closely for other signs of habitability.

This is what we have with Gliese-12b. It was found in data from the TESS exoplanet-hunting telescope, and Dholakia, his co-lead author Larissa Palethorpe of the University of Edinburgh and University College London, and their team followed up with a number of different telescopes to confirm that the TESS detecting was legit.

They found that the exoplanet has a radius almost exactly the same as Earth's, and orbits its host star once every 12.76 days. Here in the Solar System, that would be way too close for comfort – but the star Gliese-12 is a red dwarf, much cooler and dimmer than the Sun; the radiation the exoplanet receives is about 1.6 times the radiation Earth gets from the Sun.

The estimated surface temperature of the exoplanet is 42 °C (107 °F). Earth, by comparison, has an average surface temperature of 15 °C (59 °F).

Whether or not the exoplanet has an atmosphere could play a huge role in what the surface conditions are like, though.

"We are quoting the planet's 'equilibrium temperature', which is the temperature the planet would be if it had no atmosphere," Dholakia says.

"Much of the scientific value of this planet is to understand what kind of atmosphere it could have. Since Gliese-12b gets in between the amount of light as Earth and Venus get from the Sun, it will be valuable for bridging the gap between these two planets in our Solar System."

potentially habitable earth-sized world discovered just 40 light-years away

An illustration with different interpretations of Gliese-12b compared to Earth, from a bare rock, to a thick, Venus-like atmosphere. ( NASA/JPL-Caltech/R. Hurt, Caltech-IPAC )

Gliese-12b gets about 85 percent of the radiation received by Venus – but Venus is covered in a thick, choking atmosphere that generates a greenhouse effect, resulting in an average surface temperature of 464 °C (867 °F).

"It is thought that Earth's and Venus's first atmospheres were stripped away and then replenished by volcanic outgassing and bombardments from residual material in the solar system," Palethorpe says.

"Earth is habitable, but Venus is not due to its complete loss of water. Because Gliese-12b is between Earth and Venus in temperature, its atmosphere could teach us a lot about the habitability pathways planets take as they develop."

Due to its proximity to Earth, radius, position at the edge of the habitable zone of its host star, and low flare activity of that star, Gliese-12b represents possibly the best candidate yet for studying the emergence and evolution of habitability.

The researchers hope that they'll be able to recruit JWST for a closer look, to see if it has an atmosphere, and what that atmosphere is made of.

"JWST will probably be able to give us a clear picture of what its atmosphere looks like. Right now, the atmosphere of a planet is probably the greatest significant unknown that makes or breaks any claims of habitability," Dholakia tells ScienceAlert. "In other words, the hypothesis that this planet is habitable is very exciting, but it's particularly exciting that we can actually test this hypothesis clearly. We can also extend these findings to other potentially habitable planets around red dwarfs – the most common kind of star in our galaxy."

The research has been published in the Monthly Notices of the Royal Astronomical Society.

OTHER NEWS

17 minutes ago

Apple exec explains why you wouldn't want to run Apple Intelligence on your older iPhone

17 minutes ago

Queen’s LIVE: Tennis scores with Andy Murray in deciding set after Carlos Alcaraz win

17 minutes ago

Pogacar's army: Yates, Almeida, and Ayuso ready for Tour de France with strong UAE team management

17 minutes ago

This hasn’t happened to restaurant spending since the pandemic

17 minutes ago

Raiders training camp report dates revealed

17 minutes ago

Germany wary of 'under pressure' Hungary, says Nagelsmann

17 minutes ago

People call these perfumes 'basic' but I fundamentally disagree—in fact, these 9 smell really luxurious

17 minutes ago

Chiefs star Isaiah Buggs accused of 'dragging the mother of his child down stairs and injuring her' after domestic violence arrest

17 minutes ago

Andy Murray drops fresh retirement hint less than TWO WEEKS before Wimbledon... as three-time Grand Slam winner beats Alexei Popyrin at Queen's in his 1,000th match

17 minutes ago

Video: Tartan Army invasion warms the heart of hosts and even a sobering on-field surrender can't dampen the mood

20 minutes ago

Outdoor maze and twilight markets coming to Mandurah for winter school holidays

20 minutes ago

State Goverment reveals Thomas Dambo’s Giants of Mandurah exhibition a towering success for Peel region

20 minutes ago

Notre Dame staff parking bays to be made available to public outside of teaching hours

20 minutes ago

Scientists calling for protection of Rockingham’s hammerhead sharks similar to whales

21 minutes ago

Is Sha'Carri Richardson running in the 2024 Paris Olympics? Latest on star sprinter

21 minutes ago

FIFA, UEFA oppose Italian plan to oversee club finances, says FIGC chief

21 minutes ago

Jake Paul to fight Bare Knuckle's Mike Perry

21 minutes ago

Hungary must be perfect to even get a draw against Germany, says coach

21 minutes ago

HSBC breached money laundering rules in Switzerland, watchdog says

21 minutes ago

Royal Ascot 2024: have racehorses reached peak speed?

21 minutes ago

Lakers News: Jeanie Buss Under Fire Amid Coaching Search

21 minutes ago

Thousands of England fans left stranded on platforms

21 minutes ago

Summer solstice 2024: Chicago's longest day of the year takes place Thursday

22 minutes ago

Here’s what Stocks & Shares ISA investors are buying today!

22 minutes ago

A Mysterious Object Is Emitting Microwaves in Deep Space. It's Unlike Anything Ever Known.

22 minutes ago

Inflation expected to hit 2% target - what it means for interest rates

22 minutes ago

Five things that lower your sperm count and how to boost it

22 minutes ago

The Spurs roster is reaching a tipping point

22 minutes ago

Tips On How To Increase Distance By Controlling The Spin Driver

22 minutes ago

Supreme Court strikes down bump stock ban: Letters to the Editor — June 18, 2024

22 minutes ago

Mysterious monolith appears on hiking trail near Las Vegas - sparking wild speculation about where it came from

23 minutes ago

Ajax consider cut price deal with Burnley for Netherlands striker Wout Weghorst

26 minutes ago

ABS challenge system set to be used in Triple-A starting June 25

26 minutes ago

Oilers' goal to win Game 5 vs. Panthers, 'drag them back to Alberta'

26 minutes ago

ABS challenge system set to fully be used in Triple-A

26 minutes ago

Sky-Fever with Angel Reese, Caitlin Clark tops WNBA ratings

26 minutes ago

Assault on US avocado inspectors in Mexican state led to suspension of inspections

26 minutes ago

Judge in Trump classified documents case to hear validity of special counsel's appointment, gag order request

28 minutes ago

Lawmakers prepare to grill Boeing CEO David Calhoun in new hearing as planemaker flounders

28 minutes ago

“People Are Going To Turn Into A**holes”: ‘SNL’ Boss Lorne Michaels On Fame, Retirement & Cost-Cutting