Imagine if an Earth-sized planet was placed in close orbit around an M dwarf star. Because M dwarfs are some of the most common stars, it’s more than a question.
A group of astronomers are studying the planet. GJ 1252bThe answer is not pretty, but it was found.
This planet receives a lot heat because it is so close to its star. It is also dangerous because of its proximity to its star.
Michelle Hill, University of California Riverside astrophysicist who co-authored a recent paper, stated that “the pressure from the star’s radiation is immense. Enough to blow a world’s atmosphere apart.” PaperGJ 1252b was the focus.
It is 65 light-years away from Earth. It orbits its star twice per 24 Earth hours. This planet is inhospitable due to the star’s heat.
This isn’t too dissimilar to MercuryIn our solar system. There is no atmosphere on Earth and it rotates around the Sun. Actually, Earth loses some atmosphere due to solar activity.
But, other processes and volcanism release gases back into the atmosphere. Earth is fortunate; planets such as Mercury and GJ 1252b, however, are not. That has huge implications when searching for life-friendly universes.
What do you think about M Dwarf Stars
Our galaxy contains millions to millions of M dwarf star clusters. They are about one-tenth to two thirds the size of the Sun. They can also be active and send outbursts or flares through their systems. Many have at least one planet within their habitable zone, and many others scattered across the sky.
This is not a good combination if you are trying to find life on these planets. The stellar activity that destroys planetary atmospheres also eliminates any chance of life on these worlds.
Due to the sheer number of M dwarfs, the number planets that do support life may be reduced. This is not good news for planets such as GJ 1252b.
Hill stated that it was possible for this planet’s conditions to be a negative sign for other planets further away from the star.
“This is something that we’ll be learning from the James Webb Space Telescope, which will be looking for planets similar to these.”
Although M dwarfs can be a threat to the atmosphere, it is not all doom.
For example, M dwarfs are common among the 5,000 stars of Earth’s Solar Neighborhood. Even if only a small fraction of them destroy their planets to uninhabitability, at least 1,000 other stars (not all of which are M dwarfs), could create conditions conducive for life on these worlds.
“If a planet is sufficiently far from an M dwarf, it may retain an atmosphere. Hill stated that we cannot yet conclude that all rocky planets surrounding these stars are subject to Mercury’s fate.
“I remain optimistic.”
GJ 1252b Atmosphere
Interesting science lies behind the mysterious situation at GJ1252b. Astronomers used Spitzer Space TelescopeData to evaluate the infrared radiation of the planet due to a secondary eclipse that blocked its light.
These measurements revealed that the star blasts planets. Daytime surface temperatures range around 1,227 degrees Celsius (2,242 degrees Fahrenheit). It’s hot enough for melting copper, gold, and silver.
Due to the assumed low surface pressure and heat, researchers concluded that there wasn’t an atmosphere. Let’s pretend for a second that there was a carbon dioxide atmosphere. It would trap heat and possibly allow the blanket to continue to exist.
It turns out, however, that GJ 1252b doesn’t have the same luck.
“The planet could have 700x more carbon than Earth, but it wouldn’t have an atmospheric layer.” It would accumulate initially, but then gradually taper off, and erode away,” Stephen Kane, UCR physicist and co-author of the study, said.
If this study is true for a large number of M dwarf stars, it will shift the search to find habitable planets towards other candidates.
This article was originally published in Universe Today. Learn more Original article.
