Explanation: A new chapter in space flight began on 1950 July with the launch of the first rocket from Cape Canaveral, Florida: the Bumper 2. Shown above, the Bumper 2 was an ambitious two-stage rocket program that topped a V-2 missile base with a WAC Corporal rocket. The upper stage was able to reach then-record altitudes of almost 400 kilometers, higher than even modern Space Shuttles fly today. Launched under the direction of the General Electric Company, the Bumper 2 was used primarily for testing rocket systems and for research on the upper atmosphere. Bumper 2 rockets carried small payloads that allowed them to measure attributes including air temperature and cosmic ray impacts. Seven years later, the Soviet Union launched Sputnik I and Sputnik II, the first satellites into Earth orbit. In response, in 1958, the US created NASA.
Explanation: What's up on planet Earth? A truly global answer has now been created by the Global Land One-km Base Elevation (GLOBE) Project. Pictured above is the best digital elevation map yet created for our home planet, a map it took over ten years to make that incorporates data provided by many different countries from around the world. The relief map is color coded with sea level shown in black, relatively low areas shown in green, higher areas shown in brown, and the highest areas shown in white. Can you find your hometown? Clicking on the map will bring up a higher resolution version. Even more detailed versions are also available.
Explanation: Welcome to the December Solstice, first day of winter in the north and summer in the southern hemisphere of planet Earth. Today, 12-21-01, the Sun reaches its southernmost declination in the sky at 19:21 Universal Time. Just a short week ago, as the Sun approached the end of its annual journey south, it was eclipsed by the Moon. Observers in Costa Rica witnessed a fleeting annular eclipse with the Moon surrounded by a dramatic bright ring as it covered about 96 percent of the visible solar surface during the maximum phase. But from most of the Americas, this eclipse was partial ... and skies were often partially cloudy! Public Television Engineer Stan Richard captured this view near Des Moines, Iowa, USA. Taken close to eclipse maximum for his location, the sharp, silhouetted edge of the Moon is visible through the clouds in the lower left quadrant of the solar disk.
Explanation: A road trip from Ankara to the Mediterranean coast southeast of Antalya, Turkey found clear skies and splendid scenery for astrophotographer Tunc Tezel's viewing of the 2001 Leonid meteor storm. There he captured this dream-like image of a fireball meteor near the twilit horizon, reflected in calm ocean waters. Lights from coastal dwellings and nearby islands are seen in the foreground with brilliant Sirius shining as the brightest star in the heavens, visible in the constellation Canis Major at the upper right. Many enthusiasts who made special trips to view this November's Leonids were rewarded with similar spectacles of the fireball-rich storm. Airborne astronomers too had much to be thankful for as Leonid observations from a specially equiped aircraft flying at 40,000 feet produced bountiful data on the chemical composition of these dust grains from a comet's tail.
Explanation: Returning from orbit, space shuttles enter the atmosphere at about 8 kilometers per second as friction heats their protective ceramic tiles to over 1,400 degrees Celsius. By contrast, the bits of comet dust which became the Leonid meteors seen on November 18, 2001, were moving at 70 kilometers per second, completely vaporizing at altitudes of around 100 kilometers. In this single 5-minute time exposure, three Leonid meteors are shooting through skies above Spruce Knob, West Virginia, USA. Background stars are near the constellation Orion. The brightest meteor, a fireball, dramatically changes colors along its path and leaves a smokey persistant trail drifting in high-altitude winds. From that extremely dark site, at an elevation of 1,200 meters, astrophotographer Jerry Lodriguss reports, "We observed [a zenithal hourly rate of] about 3,600 at 10:30 UT and very high rates from 9:30 UT until well into the start of astronomical twilight at 10:50 UT. It was quite a spectacular storm, with bolides going off like flashbulbs, green and red fireballs and other fainter Leonids in all parts of the sky."
Explanation: Three years ago, results were first presented indicating that most of the energy in our universe is not in stars or galaxies, but is tied to space itself. In the language of cosmologists, a large cosmological constant is directly implied by new distant supernovae observations. Suggestions of a cosmological constant (lambda) are not new -- they have existed since the advent of modern relativistic cosmology. Such claims are not usually popular with astronomers, though, because lambda is so unlike known universe components, because lambda's value appears limited by other observations, and because less-strange cosmologies without lambda have previously done well in explaining the data. What is noteworthy here is the seemingly direct and reliable method of the observations and the good reputations of the scientists conducting the investigations. Over the past three years, two independent teams of astronomers have continued to accumulate data that appears to confirm the unsettling result. The above picture of a supernova that occurred in 1994 on the outskirts of a spiral galaxy was taken by one of these collaborations. Still, extraordinary claims require extraordinary evidence, and so cosmologists the world over continue to await more data and confirmation by independent methods.
Explanation: Is star AE Aurigae on fire? Although surrounded by what may look like smoke, the object known as the "flaming star" creates energy primarily by nuclear fusion, like other stars. Fire, typically defined as the rapid molecular acquisition of oxygen, happens only when sufficient oxygen is present and is not important in such high-energy, low-oxygen environments such as stars. The material that appears as smoke is mostly interstellar hydrogen, but does contain smoke-like dark filaments of carbon-rich dust grains. The AE Aurigae region was imaged by the KPNO 0.9-meter telescope and is shown above in false but representative colors. The star AE Aurigae itself is very bright, young, blue, and known as a runaway star since it appears to have been ejected from the Orion Nebula region about 2.7 million years ago.