A compelling new study has revealed potentially life-harboring worlds mostly along the distant galactic peripheries of the Milky Way.
Based on a complex simulation study, researchers from the University of St. Andrews have pinpointed possibly inhabitable celestial neighborhoods with the potential to harbor extraterrestrial life within the dark confines of countless outlying stellar systems.
According to the study, the likelihood of identifying ‘life-sustaining’ star systems improves the farther away one treads from the bustling galactic core, where perpetually imploding stars and colliding star-clusters render any prospect of alien life unsustainable. The galactic center, home to the grandest concentration of stars is therefore among the least likely hot-spots for extraterrestrial evolution. The study advances that many stars sprinkled across the inner spiral arms of the Milky Way may in fact foster potentially habitable worlds but most of these are likely to endure the wrath of punishing stellar explosions from time to time.
The study accentuates the exceedingly inhospitable and destructive character of the Milky Way as opposed to other giant elliptical galaxies which are more three-dimensional in nature and devoid of structure with stars exhibiting random orbits around the center. According to physicist Duncan Forgan, who lead the study, computer simulations modeled an entire Milky Way galaxy and the neighboring Andromeda and Triangulum galaxies.
“We’re the first to look at how the history of galaxies affects their habitability. Basically every star has a planet, on average, which is pretty mind-boggling”
However, a recent study probing 150,000 neighboring galaxies has disclosed that the Milky Way galaxy can hardly be dubbed “a cradle of life” with the power to spawn habitable, Earth-like worlds. On the contrary, the most likely candidates are possibly the larger, obscure, and more distant galaxies.
A galactic habitable zone is the region of a galaxy from where life is most likely to originate. According to Harvard University Researcher Abraham Loeb, “The habitable zone is commonly defined in reference to a distance from a luminous source, such as a star whose heat maintains the surface of a rocky planet at a temperature of 300K, allowing liquid water to exist and the chemistry of ‘life as we know it’ to operate”
One of the most basic prerequisites for the existence of life around a star is the potential of that star to produce a terrestrial planet of sufficient magnitude to sustain it. Such planets need to retain liquid water on their surface, observe a precise orbiting pattern around their parent star and provide a long-term habitat for animal-like aerobic life in order to be characterized as “habitable.”
We know from research that every star perishes at some point. Star systems closest to the center of most spiral galaxies are generally bereft of life as their scorching suns invariably expand into Giants. However, drifting farther outward and inhabiting the fringes, newly-spawned stars and planets are quite capable of nurturing extraterrestrial life.
According to Astronomer Neil Gehrels of NASA’s Goddard Space Flight Center, rare radiation erupting from “Gamma Ray” bursts constitutes a far more portentous threat to habitable planets than supernova explosions.
“There may be some uncertainty in the distance range and rate of supernovae. But their basic idea has got to be right that there are regions in our galaxy where there’s too much star formation going on”.
The simulation study also ventured into the obscure depths of galactic evolution, attempting to explore the staggering influence of gravity upon neighboring galaxies, effectively setting them on a cataclysmic collision course against each other. For instance, it has already been established that the Milky Way and Andromeda galaxies are doomed to collide in roughly 4 billion years from now.
Some experts believe that scientists have yet to capture the details of individual stars and their planetary systems in order to derive plausible conclusions. Until then, they can only rely on probable estimations about stellar explosions and their ensuing impact on potentially habitable worlds.
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