The new study, using archived NASA data, demonstrates that these seemingly nearby structures are in fact distant, and giant versions of typical spiral galaxies, like our own. These rare super spiral galaxies sing a siren's song to curious researchers who try to find a solution to the intriguing mystery of how such behemoths could have arisen. The billions of starlit galaxies that inhabit our Universe today were born a very long time ago, and their stellar inhabitants lit up what was previously an ancient swath of featureless darkness. This brilliant cosmological fireworks display occurred less than a billion years after the Big Bang birth of the Universe almost 14 billion years ago. The prevailing, and most recent, explanation for the emergence of galaxies so very long ago--playfully referred to as the "bottom-up" theory--indicates that large galaxies were uncommon inhabitants of the ancient Universe, and that they finally attained their large and majestic sizes as a result of mergers occurring between considerably smaller, shapeless protogalactic blobs. Disk galaxies, such as our Milky Way, are famous for their starlit arms. However, there is another class of galaxies that display less well-defined structures, termed lenticular galaxies. Lenticulars, like their spiral cousins, sport flattened, circular regions composed of gas and dust. Indeed, lenticulars are defined by their display of pancake-shaped regions of dust and gas that distinguish them from their elliptical galactic relatives. In contrast to their spiral kin that display structure and organization, ellipticals are more three-dimensional, and show very little in the way of structure. The sparkling stellar constituents of ellipticals travel in, more or less, random orbits around the center of their host galaxies. Lenticular galaxies are considered to be intermediate structures between spirals and ellipticals. This is the reason why ellipticals are frequently referred to as "armless spiral galaxies," because they display a bulge, but no indication of pin-wheel-like spiral arms. According to the bottom-up theory of galactic birth, large galaxies ultimately attained their enormous and majestic sizes as a result of mergers between smaller proto-galaxies zipping around in the ancient Universe. The earliest galaxies furiously gave birth to brilliant and sparkling neonatal proto-stars. Primordial star-burst galaxies were only about one-tenth the size of our Milky Way, but they were just as fabulously fiery with blasts of starlight because of these amazingly furious episodes of starry fireworks. Galaxies were born in the featureless, dark swath that was the primordial Universe when opaque clouds of primarily hydrogen gas gathered together along massive filaments of invisible dark matter. Even though scientists have not as yet determined the identity of the particles that compose the dark matter, it is generally thought that it is not composed of so-called "ordinary" atomic matter, termed baryonic matter. The very badly misnamed "ordinary" atomic matter is the truly extraordinary material that composes stars, planets, moons, and people literally all of the atomic elements listed in the familiar Periodic Table. The very extraordinary "ordinary" atomic matter composes a mere 4.6% of the Universe, while dark matter accounts for a considerably more abundant 24% of it. The lion's share of the Universe 71.4% of it is made up of the truly weird and mysterious dark energy. Dark energy is a bizarre substance, thought by many scientists to be a property of space itself--and it is causing the Universe to speed up in its relentless expansion. In the very ancient Universe, especially dense regions of dark matter exerted an irresistible gravitational pull on wandering, floating clouds of pristine gas. Dark matter does not interact with atomic matter or electromagnetic radiation except through the force of gravity. However, because it does interact with "ordinary" atomic matter, and it warps and bends the path light takes (gravitational Lansing), it shows its ghostly presence in the Cosmos despite its haunting invisibility. Gravitational lending was first proposed by Albert Einstein when he came to the realization that gravity had the ability to warp and bend traveling light and therefore exert lens-like effects. Ghostly and strange, the invisible dark matter trapped clouds of pristine gas. Thus, these clouds of ancient gases became the strange cradles of the first generation of brilliant newborn stars that lit up the previously dark and featureless Universe. The massive filaments of dark matter that spun a mysterious Cosmic Web throughout Space and Time, snatched up its baryonic prey until the trapped clouds of gas formed blobs that sunk down, down, down like black sequins into the centers of these phantom-like, ghostly, and invisible halos of dark matter. Slowly, relentlessly, the swirling sea of primordial gases and the haunting, eerie, phantom-like dark matter, floated throughout the primordial Universe, combining together to ultimately create the distinct and familiar structures that we observe today. Areas of greater density within the filaments of dark matter, weaving the mysterious Cosmic Web, flowed through the entire early Universe and became the precious seeds from which the galaxies emerged. The gravitational lure of those primordial seeds slowly embraced the ancient gases, which then formed ever tighter and tighter clouds. Most astronomers think that these clouds of gas began to gather together in clusters, and that these proto-galaxies, both large and small, performed a strange dance together that created increasingly larger and larger galactic structures. The proto-galaxies danced around together as the result of gravity, forming increasingly vast structures destined to become the enormous, majestic galaxies of our Cosmos. Like bits of dough in the hands of a pastry chef, the proto-galaxies smacked into each other to form ever-larger masses. The early Universe was much smaller then it is now and extremely crowded. Therefore, the proto-galaxies frequently bumped into one another and stuck together.
No comments:
Post a Comment