These exoplanets have the potential to be habitable, and maybe replace Earth one day

Science has identified hundreds of planets outside our solar system, called exoplanets. Some seem very similar to ours and appear to fulfill the conditions to be habitable.

Several space agencies have studied exoplanets, but none has been confirmed as habitable. However, new tools are helping to further understand them.

Image: Poster compilation from NASA Exoplanet Exploration Program-JPL/exoplanets.nasa.gov

Like Earth, a planet must meet many conditions to be considered potentially habitable. The scale used to classify the planets is the Earth Similarity Index (ESI).

Planets must be rocky to host life as we know it. Two types of exoplanets meet this condition: Super-Earths, more massive than our planet, and Terrestrial planets, similar to ours.

According to NASA, the habitable zone is the distance from a star at which liquid water could exist on a planet's surface. Being in the habitable zone is fundamental to host life.

A similar atmosphere to Earth is also fundamental for life as we know it. That is why newer projects like the James Webb space telescope study exoplanets' atmospheres.

The University of Puerto Rico and its Planetary Habitability Laboratory has a catalog of habitable exoplanets, for which researchers consider all the factors we have mentioned.

Here are the planets that are most likely to host life according to their list, arranged by their similarity to Earth. All the images are artistic interpretations.

Teegarden's Star B is slightly larger than Earth and has an ESI of 0.95/1. It completes an orbit every 4.9 days. It was discovered in 2019, and it is 12 light years away.

Image: NASA / Exoplanet Catalog

TOI-700 d was the first Earth-size habitable-zone planet discovered by NASA's Transiting Exoplanet Survey Satellite (TESS). It is located 100 lightyears away and has an ESI of 0.93.

Image: NASA's Goddard Space Flight Center - https://www.jpl.nasa.gov/spaceimages/images/largesize/PIA23408_hires.jpg

Kepler-1649 c is located about 300 lightyears away from Earth. It has an ESI of 0.92. The image is an artistic impression of how the planet might look.

Image: NASA/Ames Research Center/Daniel Rutter - https://images.nasa.gov/details-ACD20-0044-002

TRAPPIST-1 d is about 30% of the mass of the Earth. It is located in the TRAPPIST-1 system, approximately 40 lightyears away, with six other rocky planets orbiting closely to its star. Its ESI is 0.92.

Image: NASA/JPL-Caltech - Cropped from PIA22093: TRAPPIST-1 Planet Lineup

LP 890-9 c (ESI of 0.91) orbits near the inner edge of its star's habitable zone. It is located 105 lightyears away in the Eridanus constellation. It is slightly bigger than the Earth and was discovered in 2022.

Image: NASA / Exoplanet Catalog

Proxima Cen b is the closest potentially habitable exoplanet. It orbits Proxima Centauri, which is part of the triple star system Alpha Centauri, 4.2 lightyears away. Its ESI is 0.87

Image: ESO/M. Kornmesser - (https://www.eso.org/public/images/ann16056a/)

K2-72 e orbits within the habitable zone of the red dwarf star K2-72, and has an ESi of 0.87. It is located about 217.1 lightyears away from Earth in the Aquarius constellation. It is rocky and has a mass of 2.2 Earths.

Image: NASA / Exoplanet Catalog

GJ 1002 b mass is 1.08 Earths. It takes 10.3 days to complete one orbit of its star and is located 16 lightyears away. It was discovered in 2022. Its ESI is 0.86.

Image: NASA / Exoplanet Catalog

GJ 1061 d is a super Earth exoplanet: its mass is 1.64 Earths. It takes 13 days to complete one orbit around its red dwarf star. It is 12 light-years away from Earth and has an ESI of 0.86.

Image: NASA / Exoplanet Catalog

Right next to GJ 1061 b is GJ 1061 c, another super Earth exoplanet with the same ESI. Its mass is 1.74 Earths, and it completes an orbit in 6.7 days. It sits closer to its star than its brother GJ 1061 d.

Image: NASA / Exoplanet Catalog

Ross 128 b (0.86 ESI) has a mass of 1.4 planet Earths. It completes an orbit around its star every 9.9 days. It is 11 light-years away.

Image: NASA / Exoplanet Catalog

GJ 273 b is almost triple the size of Earth. It is 19 light-years away, which means it would take 22 million years to get there by jet. It completes an orbit every 18.6 days, and its ESI is 0.85.

Image: NASA / Exoplanet Catalog

Kepler-296 e is almost triple the size of Earth. It takes around a month to complete an orbit and is 545 light-years away. Its ESI is 0.85.

Image: NASA / Exoplanet Catalog

TRAPPIST-1 e is slightly smaller than Earth and has an ESI of 0.85. It orbits the same system as Trappist-1 d, right next to it. It completes an orbit every 6.1 days and is 41 light-years away.

Image: NASA / Exoplanet Catalog

Kepler-442 b's mass is 2.36 Earths. It takes 112.3 days to complete one orbit of its star, and its ESI is 0.84. The only problem is that it is a thousand light-years away. It would take 7 billion years to get there at the speed of a bullet train.

Image: NASA / Exoplanet Catalog