Colstan
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Growing up as a child, there's a good chance that an educator or relative told you that we live in an average solar system, orbiting an average star, in an average galaxy. They would have been wrong.
Our Sun is a G-type main sequence star, quite large as galactic travelers go, and hovers around the 90% mark in stellar masses. Our Sun is not small, and only 7% of stars share a similar classification.
Similarly, the Milky Way is not average, either. Along with our galactic neighbor, Andromeda, these two galaxies dominate our neighborhood. While Andromeda is currently estimated to be roughly twice the mass of our home galaxy, most of the surrounding galaxies are dwarfs in comparison. Our other close neighbor, the Triangulum galaxy, is about 10% the mass of the Milky Way.
But what of Earth? What of our own solar system? That's where things get weird. NASA has, thus far, identified approximately 5,000 verified exoplanets around other star systems. We've been searching for an analog to our own system, and have come up short.
Most solar systems have planets that measure consecutively from small to large. Our solar system is a jumbled mess. As an example, imagine if the order of the planets were Mercury, Mars, Earth/Venus, Neptune/Uranus, Saturn, Jupiter. (Sorry, no Pluto, but it's still a real planet to me, damnit!) That's the typical configuration of an average solar system. The first few million years of our system's existence were unusually chaotic and violent.
Then there are gas giants. When astronomers first started spotting planets, they most commonly found what are known as "hot Jupiters", or large gas giants orbiting very close to the host star. With more precise observation, it appears that only about 10% of solar systems host large gas giants. We have two.
Then there are the most common types of planets found around other star systems. One type are what are known as super Earths, which are rocky planets that are generally two-to-three times as massive as our home planet. The other most plentiful exoplanets are called sub-Neptunes, small gas planets which often have a mass half that of Neptune. These two categories combine to make up about 75% of all planets discovered, yet our own solar system hosts neither a super Earth nor a sub-Neptune.
Our solar system, our host star, and our home galaxy are all atypical compared to what we've discovered in the cosmos. This unusual configuration has made it difficult to find a reasonably close twin to our own home planet, Earth.
The challenge in finding a world like Earth is the prevalence of M-type red dwarf stars, which make up about 75% of all stars in the universe. Compared to the Sun, they're small and dim. The habitable zone, where the orbit around the star allows for liquid water, is typically within the orbit of Mercury when compared to our host system. This results in planets that are tidally locked, meaning that they constantly face their host star, much like what happens with our moon. These "eyeball planets" would have dramatically different atmospheres than the Earth.
The second major issue with red dwarfs, is that they are very active during the first billion or so years of their existence, with violent outbursts of ultraviolet radiation bathing any planets within the habitable zone, which may completely strip the atmosphere from those worlds.
Which brings us to the much famed Trappist-1, a star system that has made headlines for years now, because it features seven rocky planets, with at least two of them in the habitable zone. Trappist-1 is only 40 light years away from us, so it makes for a good candidate for observation.
With the aid of the new James Webb space telescope, astronomers are finally able to glimpse the atmosphere of one of these rocky worlds, the innermost planet, Trappist-1b. While not in the habitable zone, the detection of any atmosphere would give a good indication that there is hope for finding Earth-like worlds around red dwarfs. The early results have not been promising.
arstechnica.com
Webb has failed to find an atmosphere around Trappist-1b. These are early results, just a single planet, and definitely not final data. However, if confirmed, it would give an early indication that M-type red dwarfs are likely incapable of hosting habitable planets with a thick atmosphere, and thusly are unlikely to feature a planet similar to Earth, one which could be home to alien life.
While interesting from a scientific perspective, many astronomers believe that we should be searching similar G-type stars to our own, while expanding that search to less massive K-type stars, and hard pass on the red dwarfs. This would be particularly vexing, since our closest stellar neighbor, Proxima Centauri, hosts a rocky planet within the habitable zone.
The search continues, perhaps red dwarf systems will surprise us. However, it's more likely that they host planets that are nothing more than blasted hellscapes, barren planes of nothingness, baked for a billion years in ultraviolet light, rendering it a dark redoubt for eons. Regardless, the search continues for another Earth, but it's not likely orbiting Trappist-1.
Our Sun is a G-type main sequence star, quite large as galactic travelers go, and hovers around the 90% mark in stellar masses. Our Sun is not small, and only 7% of stars share a similar classification.
Similarly, the Milky Way is not average, either. Along with our galactic neighbor, Andromeda, these two galaxies dominate our neighborhood. While Andromeda is currently estimated to be roughly twice the mass of our home galaxy, most of the surrounding galaxies are dwarfs in comparison. Our other close neighbor, the Triangulum galaxy, is about 10% the mass of the Milky Way.
But what of Earth? What of our own solar system? That's where things get weird. NASA has, thus far, identified approximately 5,000 verified exoplanets around other star systems. We've been searching for an analog to our own system, and have come up short.
Most solar systems have planets that measure consecutively from small to large. Our solar system is a jumbled mess. As an example, imagine if the order of the planets were Mercury, Mars, Earth/Venus, Neptune/Uranus, Saturn, Jupiter. (Sorry, no Pluto, but it's still a real planet to me, damnit!) That's the typical configuration of an average solar system. The first few million years of our system's existence were unusually chaotic and violent.
Then there are gas giants. When astronomers first started spotting planets, they most commonly found what are known as "hot Jupiters", or large gas giants orbiting very close to the host star. With more precise observation, it appears that only about 10% of solar systems host large gas giants. We have two.
Then there are the most common types of planets found around other star systems. One type are what are known as super Earths, which are rocky planets that are generally two-to-three times as massive as our home planet. The other most plentiful exoplanets are called sub-Neptunes, small gas planets which often have a mass half that of Neptune. These two categories combine to make up about 75% of all planets discovered, yet our own solar system hosts neither a super Earth nor a sub-Neptune.
Our solar system, our host star, and our home galaxy are all atypical compared to what we've discovered in the cosmos. This unusual configuration has made it difficult to find a reasonably close twin to our own home planet, Earth.
The challenge in finding a world like Earth is the prevalence of M-type red dwarf stars, which make up about 75% of all stars in the universe. Compared to the Sun, they're small and dim. The habitable zone, where the orbit around the star allows for liquid water, is typically within the orbit of Mercury when compared to our host system. This results in planets that are tidally locked, meaning that they constantly face their host star, much like what happens with our moon. These "eyeball planets" would have dramatically different atmospheres than the Earth.
The second major issue with red dwarfs, is that they are very active during the first billion or so years of their existence, with violent outbursts of ultraviolet radiation bathing any planets within the habitable zone, which may completely strip the atmosphere from those worlds.
Which brings us to the much famed Trappist-1, a star system that has made headlines for years now, because it features seven rocky planets, with at least two of them in the habitable zone. Trappist-1 is only 40 light years away from us, so it makes for a good candidate for observation.
With the aid of the new James Webb space telescope, astronomers are finally able to glimpse the atmosphere of one of these rocky worlds, the innermost planet, Trappist-1b. While not in the habitable zone, the detection of any atmosphere would give a good indication that there is hope for finding Earth-like worlds around red dwarfs. The early results have not been promising.

Webb Telescope confirms nearby rocky planet has no significant atmosphere
A close look at one of TRAPPIST-1’s planets shows it’s bare and baking.

Webb has failed to find an atmosphere around Trappist-1b. These are early results, just a single planet, and definitely not final data. However, if confirmed, it would give an early indication that M-type red dwarfs are likely incapable of hosting habitable planets with a thick atmosphere, and thusly are unlikely to feature a planet similar to Earth, one which could be home to alien life.
While interesting from a scientific perspective, many astronomers believe that we should be searching similar G-type stars to our own, while expanding that search to less massive K-type stars, and hard pass on the red dwarfs. This would be particularly vexing, since our closest stellar neighbor, Proxima Centauri, hosts a rocky planet within the habitable zone.
The search continues, perhaps red dwarf systems will surprise us. However, it's more likely that they host planets that are nothing more than blasted hellscapes, barren planes of nothingness, baked for a billion years in ultraviolet light, rendering it a dark redoubt for eons. Regardless, the search continues for another Earth, but it's not likely orbiting Trappist-1.