Under what circumstances can life begin on a planet? Is water an essential ingredient? What is the correct temperature? Is the atmospheric composition ideal? How about the size and geology of the planet? These are questions that have been asked by scientists over and over again, and they can never been agreed upon to any extent. According to a new study, however, there might be a new type of theory that explains a celestial situation that could bring about alien life.
Alien life on diamond planets
According to a new study by the publication Monthly Notices of the Royal Astronomical Society, it is theoretically possible that life could blossom without an iron- and silicate-based planet. Carbon planets, which are composed of graphite, diamonds, and carbides could possibly be host to alien life as well.
Scientists have suggested that searching for a rare class of star might help find these “diamond worlds.” Carbon-enhanced metal-poor stars, or CEMP stars, formed before heavy metals crucial for life on Earth, were spread throughout the universe.
These stars may have aided in forming carbon planets through the “clumping” of carbon dust grains. While these planets lack iron and other metals generally considered essential to life, these “black-tar” worlds with similar size and mass to other Earth-like planets are still potentially capable of sustaining life.
Although these starts are lacking in iron and other heavy elements as compared to our Sun, CEMP starts have way more carbon than expected at their age. This abundance is what influenced planet formation as the “fluffy” carbon dust grains clump together to form these worlds.
“This work shows that even stars with a tiny fraction of the carbon in our solar system can host planets,” says Natalie Mashian, a graduate student at Harvard University and the study’s lead researcher. “We have good reason to believe that alien life will be carbon-based, like life on Earth, so this also bodes well for the possibility of life in the early universe.”
Fossils of the early universe
These CEMP stars are relics of the early days of the universe, so there aren’t many left, though there are still some out there. Finding these potentially habitable worlds orbiting these CEMP starts requires using the “transit technique.” This technique requires careful observation of any large objects that pass in front of the field of view of these starts, and by observing the dimming and brightening of the light as the object passes. This technique has already been utilized by the Kepler missions in finding exoplanets.
Researchers have stated that a dedicated search for exoplanets around CEMP stars can be conducted using the transit technique. “This is a practical method for finding out how early planets may have formed in the infant universe. We’ll never know if they exist unless we look,” added Mashian.
This is exciting news in the scientific world, as this new theory allows for an expanded search of what circumstances are required to support extraterrestrial life. Through research and discovery, scientists now have a much wider range of celestial bodies to study and analyze.
“These stars are fossils from the young universe,” says Mashian’s Ph.D. thesis advisor Avi Loeb from the Harvard-Smithsonian Center for Astrophysics. “By studying them, we can look at how planets, and possibly life in the universe, got started.”