One of the most common types of island universes viewed during our journey
Space news (The Hubble Tuning Fork: barred spiral galaxies) – 55 million light-years from Earth toward the constellation of Coma Berenices (Berenice’s Hair) –
First documentedin the western world by German-British astronomer William Herschel, barred spiral galaxy NGC 4394 is a member of the most common type of galaxy viewed inthe Galaxy Zoo. Estimated by astronomers to be 55 million light-years from Sol, toward the constellation of Coma Berenices, this island universeis considered a member of the Virgo Cluster.
The prototypical barred spiral galaxy, NGC 4394 has bright spiral arms sprouting from the ends of a bar cutting through its middle bulge. Sprinkled with blue, young stars its spiral arms contain fuzzy regions where stars are being formed and dark filaments of cosmic dust. Near the center of this island universe lies a region of ionized gas known as a low-ionization nuclear emission-line region (LINER). An active region displaying a specific set of emission lines in its spectra, a LINER contains mainly weakly ionized atoms of oxygen, nitrogen, and sulfur.
LINERS have been viewed relatively often during the human journey to the beginning of space and time and they’re starting to piece together their puzzle. Astronomers still need to figure out where the energy comes from to ionize the gas. Presently astronomers believe it could be due to the influence of the supermassive black hole or extreme levels of star formation. In the case of NGC 4394, gas from a nearby galaxy has likely flowed into its central region, providing a new source to fuel the process, either way.
You can learn more about galaxies with a LINER here.
Astronomers are looking at NGC 3982 and other galaxies for a supernova to study
Put your name in the history books
Astronomy News – The Milky Way use to be thought of as a spiral galaxy, but recently collected data seems to suggest to astronomers that the Milky Way could, in fact, be a barred galaxy. Either way, the human “Journey to the Beginning of Space and Time” has revealed to astronomers a seeming infinity of galaxies beyond the celestial horizon we view from Earth. Spiral galaxies abound in amazing numbers in the universe, elliptical and barred galaxies have been viewed in endless numbers beyond the celestial horizon, and none of these galaxies look exactly the same. Beyond the horizon we view from Earth, the universe astronomers view goes on and on, without an end in sight, but everything we humans have experienced has an ending and beginning. Can the universe truly go on forever, or is it conceivable that somewhere beyond the celestial horizon there exists boundaries beyond which the known universe ends and another reality exists?
Astronomers using the Hubble Space Telescope recently journeyed to spiral galaxy NGC 3982 to look for clues to these questions and others that have fascinated humans since the time of the first-star gazers. A face-on spiral galaxy first discovered by William Herschel on April 14, 1789, NGC 3982’s spiraling arms are lined with pink star-forming regions of space and time glowing with hydrogen, newborn blue star clusters, and star dust capable of providing the raw material for future generations of stars. Astronomers believe hidden in the nucleus of NGC 3982 is a generation of older stars, which become more densely packed as the distance to the center of the nucleus of NGC 3982 lessens. NGC 3982 is an amazing 68 million light-years distant in the constellation Ursa Major and is currently speeding away from the center of the Milky Way Galaxy at a recession velocity of 1187 km/s. NGC 3982 is also a smaller spiral galaxy and spans about 30,000 light years, which is only about one-third the size of our own Milky Way Galaxy.
Astronomers use the Hubble Space Telescope
Astronomers are looking at spiral galaxy NGC 3982, and other similar galaxies, in the hopes of viewing a celestial event of amazing intensity and power, a supernova. They’re currently using the instruments on the Hubble Space Telescope to look for a supernova in the spiral and other galaxies, but soon the James Webb Space Telescope will add its star gazing ability to this job. They want to check current theories on how supernova occur and possibly the types of stars that end their lives in these spectacular explosions. Their search will be primarily in the bright blue knots in NGC 3982’s spiral arms, but they’ll certainly expand their search as the human “Journey to the Beginning of Space and Time” continues to expand.
Astronomy News – The galaxies you’ll view during your “Journey to the Beginning of Space and Time” are like grains of sand on the beach, or snowflakes, with no two galaxies looking exactly the same to viewers. Astronomers have also viewed a number of different types of galaxies and they have given each a specific name, usually based on the overall shape of the galaxy. Composed of millions or even billions of individual stars, each particular type of galaxy viewed, so far, has also been given a designation, or name, by which we all can tell the difference between the individual galaxies in the infinity of galaxies we view in the night sky above us. It was Edwin Hubble who first did the work with photographic plates taken during the early part of the twentieth century that allowed him to determine the nebulous objects astronomers had been viewing for years were actually vast islands of stars we call galaxies. Edwin Hubble also cataloged the galaxies he viewed into three major classes, or types, according to their physical shape.
A percentage of the galaxies will resemble huge pinwheels and have been given the name spiral galaxies by astronomers viewing these objects. Spiral galaxies are generally composed of a bright central nucleus with older stars, with two sweeping arms of younger stars, open clusters, and diffuse nebulae unfolding in space and time. The Milky Way in which we reside is one such spiral galaxy among the multitudes of such galaxies in the universe and Sol is located about two-thirds of the way from the center of the galaxy.
Astronomers have broken down spiral galaxies into five subclasses of spiral galaxies, according to how tightly the arms of a galaxy are wrapped around the nucleus of the spiral galaxy in question. Spiral galaxies with the tightest arms are Sa spiral galaxies, Sb spiral galaxies are next in order, with more loosely armed Sc, comparatively rare Sd, and S0 spiral galaxies almost appearing to be a transitional form between spiral galaxies and another type of galaxy.
Barred galaxies exhibit an odd, bar-like feature passing through the nucleus of the galaxy, and the spiral arms of barred galaxies start to unwind from the ends of the central bar, rather than from the nucleus of the galaxy. Barred galaxies are also classified according to the tightness of the spiral arms and have designations SBa, SBb, and SBc.
Elliptical galaxies are the most plentiful type of galaxy we have viewed during the human “Journey to the Beginning of Space and Time.” Elliptical galaxies actually have no hint of spiral arms and appear as huge, oval spheres with no discernible internal structure of any kind. Elliptical galaxies are classified according to how round they appear, with E0 elliptical galaxies appearing almost perfectly spherical, E4 elliptical galaxies looking like an oddly shaped football, and E7 elliptical galaxies looking flat as compared to the other classifications. Elliptical galaxies appear to be composed mostly of older stars and you’ll notice they lack luminosity as you view them.
Infinite is a human term
Galaxies that appear to have no distinctive shape are referred to as irregular galaxies and irregular galaxies have been viewed a lot less in the night sky than the other types. This doesn’t necessarily mean irregular galaxies appear in fewer numbers in the universe, but it does mean that the percentage of the universe we have viewed from Earth appears to contain fewer irregular galaxies than the other types.
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The Human Journey to the Beginning of Space and Time.