Searching the Night Sky for a Supernova
Posted: October 25, 2010 Filed under: astronomers, Astronomical Societies, astronomy, Barred galaxies, Edwin Hubble, Elliptical galaxies, entertainment, Hubble Space Telescope, irregular galaxies, John Hopkins University, NASA, National Solar Observatory, NGC 3982, Royal Astronomical Society, space history, spiral galaxies, supernovae, the James Webb Space Telescope, the Milky Way galaxy, the Universe, William Herschel | Tags: astronomers, astronomy, galaxies, Hubble Space Telescope, James Webb Space Telescope, Journey to the Beginning of Space and Time, NGC 3982, spiral galaxies, William Herschel Leave a comment »
If you see a supernova, it could be your big moment in life?
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 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 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.
An Infinite Number of Galaxies?
Posted: October 25, 2010 Filed under: astronomers, astronomy, Barred galaxies, Edwin Hubble, Elliptical galaxies, entertainment, Hubble Space Telescope, irregular galaxies, spiral galaxies, Spitzer Space Telescope, star evolution, the James Webb Space Telescope, the Milky Way galaxy, the Universe | Tags: astronomers, astronomy, barred galaxies, Edwin Hubble, elliptical galaxies, galaxies, irregular galaxies, Journey to the Beginning of Space and Time, spiral galaxies 2 Comments »
Just how many galaxies is an infinite number, anyway?
Just what do we humans mean by infinite galaxies?
So many planets, so much diversity! Can life really be limited to Earth?
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 on the human “Journey to the Beginning of Space and Time” that they have each given 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 catalogued the galaxies he viewed into three major classes, or types, according to their physical shape.
Within the pinwheels of this spiral galaxy new planets and possibly new life could be born
A percentage of the galaxies you’ll view during your “Journey to the Beginning of Space and Time” 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 spiral 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 spiral galaxies, and S0 spiral galaxies almost appearing to be a transitional form between spiral galaxies and another type of galaxy.
NGC 1365 is a barred galaxy astronomers have been studying
Barred galaxies exhibit an odd, barlike 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.
Centaurus is an elliptical galaxy with an easily seen barlike feature
Elliptical 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.
Barnard is an irregular galaxy with no distinct shape
Galaxies that appear to have no distinctive shape are referred too 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.
