A scientist claimed that the planetary systems that astronomers discovered are not the same as our own. Is it necessary that our solar system is unique? We haven't figured it out yet.
Nothing nearly like our home planet has been discovered among the hundreds of planets verified to be in orbit around other stars. Other planets in the same size range as Earth? By the bushel, of course. But what about orbital a star similar to our Sun at a similar distance? So far, it's just been one isolated occurrence. The one we're standing on.
The technological complexity of discovering a sister planet is likely to have a significant role.
Jessie Christiansen, a research scientist at NASA's Exoplanet Science Institute and an expert in exoplanet demography, does not believe "Earths" would be rare but says the scientific literature on the subject is "all over the place."
Scientists say that additional data is needed to estimate the frequency of planets that are comparable to Earth in size and condition.
Earth's Weirdness Doesn't Stop There
The strangeness of our solar system doesn't stop at Earth, SciTechDaily said. Our unique configuration - tiny, rocky worlds in the closest orbits, large gas giants further out - is also something we haven't seen anywhere else in close parallel. It's unclear if this is because they're actually rare or because they're difficult to find.
Every 12 years, Jupiter completes one orbit around the Sun. However, Jupiter-like planets in lengthy orbits are uncommon orbiting other stars, which might be significant. According to scientists, Jupiter may have actually paved the way for Earth to become a livable world. The massive planet's tremendous gravity might have sucked up tiny rocky fragments that would have otherwise slammed into Earth, sterilizing it just as the life began.
Future space telescopes might look for evidence of oxygen, methane, or carbon dioxide in the atmospheres of distant, rocky worlds - in other words, an atmosphere similar to our own.
For the time being, we are in the dark. There might be a lot of Earth-like planets around Sun-like stars. They might also be the galaxy's genuine oddballs.
Telescopes That Measure Planets' Weirdness
According to Bolly Inside, the telescopes, both in space and on the ground, use two basic ways to identify planets orbiting other stars: wobbles and shadows.
The radial velocity approach, often known as the "wobble" method (per SciTechDaily report), follows the slight back-and-forth motion that occurs as circling planets drag their star this way and then that due to gravity. The planet becomes "heavier" - that is, its mass increases - as the drag becomes stronger.
Planet-hunting telescopes look for a small drop in brightness when a planet crosses the face of its star - a crossing known as a "transit" - in the search for shadows. The broader the planet, the greater the dip.
Giant planets are easier to identify than tiny planets in both scenarios. Tiny, rocky planets the size of Earth show up considerably better against tiny stars known as red dwarfs during transits.
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They produce a larger shadow, which blots out proportionally more of a minor star's light, making it easier for sensors like NASA's TESS satellite observatory to discover them. When an Earth-sized planet passes by, a Sun-sized star dims less, making transits more difficult to detect.
There's also the problem of time to consider. One rotation of a planet orbiting a star at Earth's distance from the Sun would take around 365 days, precisely like our planet's "year." To validate such an orbit, your telescope would have to gaze at that star for 365 days to capture even one transit - and you'll need to observe at least two or three of these transit signals to be sure it's genuinely a planet.
Because of these challenges, such planets are mainly out of reach for today's technology. We've discovered a slew of tiny rocky planets, but they all circle red dwarf stars.
Red dwarfs are significantly more numerous in our galaxy than bigger yellow stars like the Sun. That still allows room for billions of Sun-like stars to orbit them, as well as perhaps a considerable number of livable, Earth-sized worlds.
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