Featured November Print
Cygnus Loop Supernova Blast Wave
This is an image of a small portion of the Cygnus Loop supernova remnant, which marks the edge of a bubble-like, expanding blast wave from a colossal stellar explosion, occurring about 15, 000 years ago. The HST image shows the structure behind the shock waves, allowing astronomers for the first time to directly compare the actual structure of the shock with theoretical model calculations. Besides supernova remnants, these shock models are important in understanding a wide range of astrophysical phenomena, from winds in newly-formed stars to cataclysmic stellar outbursts. The supernova blast is slamming into tenuous clouds of insterstellar gas. This collision heats and compresses the gas, causing it to glow. The shock thus acts as a searchlight revealing the structure of the interstellar medium. The detailed HST image shows the blast wave overrunning dense clumps of gas, which despite HST's high resolution, cannot be resolved. This means that the clumps of gas must be small enough to fit inside our solar system, making them relatively small structures by interstellar standards. A bluish ribbon of light stretching left to right across the picture might be a knot of gas ejected by the supernova; this interstellar "bullet" traveling over three million miles per hour (5 million kilometres) is just catching up with the shock front, which has slowed down by ploughing into interstellar material. The Cygnus Loop appears as a faint ring of glowing gases about three degrees across (six times the diameter of the full Moon), located in the northern constellation, Cygnus the Swan. The supernova remnant is within the plane of our Milky Way galaxy and is 2, 600 light-years away. The photo is a combination of separate images taken in three colors, oxygen atoms (blue) emit light at temperatures of 30, 000 to 60, 000 degrees Celsius (50, 000 to 100, 000 degrees Farenheit). Hydrogen atoms (green) arise throughout the region of shocked gas. Sulfur atoms (red) form when the gas cools to around 10, 000 degrees Celsius (18, 000 degrees Farenheit)
Featured November Print
The Wright Brothers First Heavier-than-air Flight
On December 17, 1903, at 10:30 am at Kitty Hawk, North Carolina, this airplane arose for a few seconds to make the first powered, heavier-than-air controlled flight in history. The first flight lasted 12 seconds and flew a distance of 120 feet. Orville Wright piloted the historic flight while his brother, Wilbur, observed. The brothers took three other flights that day, each flight lasting longer than the other with the final flight going a distance of 852 feet in 59 seconds. This flight was the culmination of a number of years of research on gliders.
Orville and Wilbur Wright's curiosity with flight began in 1878 when their father, Milton, gave them a rubber band powered toy helicopter. Although they were never formally educated, the self-taught engineers constantly experimented with kites and gliders. Bicycle shop owners by occupation, the brothers spent years designing, testing and redesigning their gliders and planes. After the successful flights of December 17, 1903, Orville and Wilbur continued to perfect their plane. In 1909 the Army Signal Corps purchased a Wright Flyer, creating the first military airplane. Although Wilbur passed away May 30, 1912, from typhoid fever, Orville remained an active promoter of aviation until his death on January 30, 1948.
The Air Age truly began with that historic flight on December 17, 1903. In 1908 the Wright Brothers designed the first military aircraft for the Army Signal Corps. Seven years later, in 1915, the National Advisory Committee for Aeronautics (NACA) became the nations leading aviation research organization, of which Orville was a member for 28 years. As the airplane became more aerodynamic and technically advanced, its uses expanded into many different directions. Military aircraft played significant roles in both World War I and World War II. The airplane made worldwide travel and exploration possible. Spaceflight would never have been realized without the pioneering achievements of the Wright Brothers
Featured November Print
A Grazing Encounter Between Two Spiral Galaxies
The larger and more massive galaxy is cataloged as NGC 2207 (on the left in the Hubble Heritage image), and the smaller one on the right is IC 2163. Strong tidal forces from NGC 2207 have distorted the shape of IC 2163, flinging out stars and gas into long streamers stretching out a hundred thousand light-years toward the right-hand edge of the image. Computer simulations, carried out by a team led by Bruce and Debra Elmegreen, demonstrate the leisurely timescale over which galactic collisions occur. In addition to the Hubble images, measurements made with the National Science Foundation's Very Large Array Radio Telescope in New Mexico reveal the motions of the galaxies and aid the reconstruction of the collision. The calculations indicate that IC 2163 is swinging past NGC 2207 in a counterclockwise direction, having made its closest approach 40 million years ago. However, IC 2163 does not have sufficient energy to escape from the gravitational pull of NGC 2207, and is destined to be pulled back and swing past the larger galaxy again in the future. The high resolution of the Hubble telescope image reveals dust lanes in the spiral arms of NGC 2207, clearly silhouetted against IC 2163, which is in the background. Hubble also reveals a series of parallel dust filaments extending like fine brush strokes along the tidally stretched material on the right-hand side. The large concentrations of gas and dust in both galaxies may well erupt into regions of active star formation in the near future. Trapped in their mutual orbit around each other, these two galaxies will continue to distort and disrupt each other. Eventually, billions of years from now, they will merge into a single, more massive galaxy. It is believed that many present-day galaxies, including the Milky Way, were assembled from a similar process of coalescence of smaller galaxies occurring over billions of years. This image was created from 3 separate pointings of Hubble. The Wide Field Planetary Camera 2 data sets were obtained by Debra Meloy Elmegreen (Vassar College), Bruce G. Elmegreen (IBM Research Division), Michele Kaufman (Ohio State U.), Elias Brinks (Universidad de Guanajuato, Mexico), Curt Struck (Iowa State University), Magnus Thomasson (Onsala Space Obs., Sweden), Maria Sundin (Goteborg University, Sweden), and Mario Klaric (Columbia, South Carolina)