Did you know that for every five Sun-like stars in our Milky Way galaxy, there might be one Earth-like planet? Recent studies have changed how we see potentially habitable worlds – which we call the habitable exoplanets. With over 5,000 confirmed exoplanets and many more being checked, finding another Earth could be closer than we think. Which planet is most like Earth, though? Do we have a contender?
NASA’s Transiting Exoplanet Survey Satellite (TESS) recently made a big find about this. They discovered an Earth-size world named TOI 700 e in its star’s habitable zone. This planet, 100 light-years away, is 95% the size of Earth and likely rocky. It’s in a system with other small, possibly habitable planets. It’s a hot spot for more research.
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This discovery was among the many discoveries we made about the planets that resemble the Earth. But which planet is most like Earth? There is more than one answer to this. TOI 700 e is one, but several Kepler planets are extremely similar to Earth and can potentially have life in them.
The Search for Planets Like Earth
Since 1995, scientists have found 160 exoplanets. The smallest one, OGLE-2005-BLG-390Lb, is 25,000 light-years away from us. It takes 10 years to orbit its star, which is three times farther than Earth is from the Sun.
Scientists look for certain features in the search for planets like Earth to determine if a planet is actually habitable and is like Earth. These include a rocky surface, temperatures right for liquid water, and an atmosphere. A magnetic field is also key for life. Scientists use certain sizes and masses to spot possible Earth-like planets.
Kepler and James Webb’s roles
The Kepler telescope is one of the biggest developments in space research after the James Webb Space Telescope – thus, the research on which planet is most like Earth. It has helped a lot in discovering these potential Earths. It found over 40 billion Earth-sized planets in our galaxy alone! The James Webb Space Telescope recently found LHS 475 b, an Earth-like exoplanet.
Kepler-452b: Earth’s Bigger, Older Cousin
Kepler-452b is one of those planets that is extremely close to Earth and has the highest potential to be an Earth for us. It’s a super-Earth that orbits a star similar to our Sun. It takes Kepler-452b about 385 days to go around its star, which is almost as long as Earth’s year. Its orbit is just a bit bigger than Earth’s, putting it in the right spot for life to exist.
The star that Kepler-452b orbits is very much like our Sun. However, it’s about 1.5 billion years older. This gives us a peek into what our solar system might be like in the future.
Key Differences and Potential Habitability
Kepler-452b is often seen as the most Earth-like planet found so far. But it’s not identical to Earth. It’s about 60% bigger in diameter, making it a super-Earth. Its star is also 20% brighter and 10% larger than our Sun.
The chance for life on Kepler-452b can be quite high. It’s in the right spot to have liquid water on its surface. But being bigger might mean a thicker atmosphere, which could cause a greenhouse effect. The biggest problem is that it’s so far away. When we look at Kepler-452b from the Earth, we see 1,400 years into the past. It’s not much, but it still can affect what we see.
TOI 700 e: A New Earth-Sized World
TOI 700 is the newest popular thing among scientists, and it is a planet most like Earth. It’s an Earth-sized planet, 100 light-years away in the Dorado constellation. It’s in a system with other planets that could support life.
TOI 700 e is almost as big as Earth, at 95% of our size. It goes around its star every 28 days, which puts it in a good spot for life. This spot is where water might be liquid on its surface, similar to Earth.
NASA’s TESS found TOI 700 e by watching the sky for stars with planets. It looks for small drops in starlight when a planet passes by. After a year of watching, TESS confirmed that TOI 700 e is real.
The TOI 700 system is special because it has more planets that could support life. There’s TOI 700 d, another planet in a good spot for life. These discoveries help us learn about the kinds of planets that could be out there.
Proxima Centauri b: Our Closest Earth-like Neighbor
Proxima Centauri B is the closest earth-like planet we’ve found so far. It orbits Proxima Centauri, the star closest to our Sun, just 4.22 light-years away. This rocky world has caught the eye of astronomers because of its star.
Proxima Centauri B was discovered in 2016 and is quite interesting. It’s a bit bigger than Earth, with at least 1.3 times our planet’s mass. It’s in the habitable zone, where water can be liquid. It orbits its star every 11.2 Earth days, much faster than our year.
NASA plans to send a probe to the Alpha Centauri system in 2069 to look for life signs. But, there are hurdles. Proxima Centauri has strong flares that could affect the planet’s ability to support life. In 2021, a flare 100 times stronger than our Sun’s was recorded. This kind of limits the possibility of water – which we thought there could be. Water is the first sign we look for when looking for life outside of Earth. At least, life is similar to ours.
Recent discoveries have found more planets around Proxima Centauri. Proxima c is bigger, and Proxima d is tiny. All in all, Proxima Centauri could host a planet or more that is potentially habitable. Maybe not Proxima B, but another planet.
Which Planet Is Most Like Earth?
Finding an exoplanet most like Earth is hard. Kepler-452b is a top choice because it’s big and old, like Earth’s twin. Kepler-452b is a super-Earth, 60% bigger than our planet. It goes around a star like the Sun, 1,400 light-years away in Cygnus. Its year is almost as long as ours, and its gravity is stronger. It might be a bit cooler than Earth. But it’s not all the same. It’s much bigger and gets more energy from its star. The system it’s in is also older, about 6 billion years old.
We need better telescopes to learn more about Kepler-452b. That’s actually the biggest hurdle we have. It’s not like we just detect a planet like we do with many other exoplanets. We need to be able to determine whether an exoplanet is habitable based on a variety of things. We must look at this closely, but we can’t.
The Role of Technology in Exoplanet Discovery
Technology has changed how we look for Earth-like exoplanets. Since the 1990s, finding potentially habitable worlds has grown a lot. Back then, we first found an exoplanet. Kepler, James Webb, and many other missions launched by NASA and other bodies have helped us a lot. Technology made us aware of our surroundings in space more than anything ever did.
TESS and its contributions
The Transiting Exoplanet Survey Satellite (TESS) that was launched in 2018 has changed everything. It’s helping us learn more about exoplanets close to us. TESS has found exciting earth-like exoplanets like TOI 700 e.
Telescopes and missions
The James Webb Space Telescope (JWST) has taken us further than any other mission ever did, and it’s not even at the beginning yet. It will study exoplanets in mid-infrared and directly image young massive planets. It’s looking directly at the beginning of the universe, which can give us a detailed look at the planets as a whole. If we know which planets are new and old, we can estimate the probability of habitability more easily.
The Astro2020 survey suggests a new project for the 2040s. This Habitable Worlds Observatory will directly image earth-like exoplanets. Many telescopes and missions are currently working and will work in the future to determine a planet that could potentially host life. Right now, the James Webb Telescope is our best shot.
Implications of Finding Earth-like Planets
The discovery of Earth-like planets is one of the important parts of the search for extraterrestrial life. We now know that only 8% of potentially habitable planets were around when our solar system began 4.6 billion years ago. This means 92% of these planets are still waiting to be discovered.
Kepler’s planet survey found there could be 1 billion Earth-sized planets in the Milky Way. There are 100 billion galaxies in the observable universe, and the potential of habitable planets is just extraordinary.
Finding habitable planets isn’t just about how many there are. It’s about finding the right conditions for life (as I always like to say it, the life that we know). Of the 5,000 discovered exoplanets, only 93 are thought to be potentially habitable. These planets are in the habitable zone of their stars, where liquid water could exist on their surfaces.
It’s important to look for potentially habitable planets, but we generally forget something. We are looking for life that we know. The universe is so vast and so unpredictable that there might be life out there that we just can’t simply fathom. They may live without water or oxygen, or they may survive under lava. You never know – evolution is extraordinary.
Conclusion
Looking for which planet is most like Earth is definitely one of the top things to search for out there in space. So far, we have some good candidates. From Kepler-452b to TOI 700 e, there are really potentially habitable exoplanets that are extremely similar to Earth. It’s a hard task, though. Like, you just can’t simply look at a planet and determine whether it’s potentially habitable or not. For example, Venus might look similar to Earth at first, but it’s very different. It has extremely hot days and a thick atmosphere full of carbon dioxide. Earth is special because of its perfect tilt and atmosphere that supports life. It’s in perfect proximity to its Sun and has a Moon that is the perfect size.
We are looking for planets like that when we want to know which planet is most like Earth. Our search for earth-like exoplanets is far from over – with telescopes like the James Webb and new missions, it’s just starting. Scientists now also think smaller planets might be more likely to have moons that could support life. We don’t know. The life we know could be the one of its kind. We might need to look for other types of lives that may exist.
FAQ
What defines an Earth-like planet?
Earth-like planets have rocky surfaces and can hold liquid water. They also have atmospheres and magnetic fields. They are similar in size and makeup to Earth.
What roles have Kepler and the James Webb Space Telescope played in discovering Earth-like planets?
Kepler found over 2,000 confirmed planets, including super-Earths, in the habitable zone. The James Webb Space Telescope will study the atmospheres of nearby planets. It will also figure out their masses and what they’re made of.
How does Kepler-452b compare to Earth?
Kepler-452b is a super-Earth in the habitable zone of a star like our Sun. It’s 50% bigger than Earth and five times heavier. It gets more energy from its star than Earth does from the Sun, but it could still be like Earth.
What makes TOI 700 e an exciting discovery?
TOI 700 e is an Earth-size planet in its star’s habitable zone. It’s part of a system with other small, potentially habitable planets. It’s 95% the size of Earth and likely rocky, as found by NASA’s TESS.
Why is Proxima Centauri b a prime target for future exploration?
Proxima Centauri B is a rocky planet near Earth’s size in the habitable zone of Proxima Centauri. It’s close to us, making it a top choice for exploration. NASA plans to send a probe to Alpha Centauri in 2069 to look for signs of life.
Which planet is considered the most Earth-like?
Many exoplanets, like Kepler-452b, TOI 700 e, and Proxima Centauri b, could be like Earth. But we need more studies to determine which one is most like our planet. Each has its own features that make it similar to Earth in different ways.
What are the implications of finding Earth-like planets?
Finding Earth-like planets changes how we see the universe and the chance of life elsewhere. The Drake equation tries to figure out the odds of intelligent life in the universe. It looks at stars, planets like Earth, and life’s chance to evolve.