When a massive star explodes, it leaves behind glowing traces called supernova remnants. Many have been studied, but it is not completely clear how much material comes off the exploding star, and how it is distributed outward. A combination of X-ray observations from Chandra Space Telescope and infrared data from the Spitzer Space Telescope allowed astronomers to see the supernova mechanism in action.
A trio of planets is now shining in our skies. Venus is rising higher in the western sky, Mars is still visible but getting fainter, but Saturn is now at its brightest for the year. Saturn is visible just about all night, rising at sunset, highest in southern sky at midnight.
NASA's radar experiment aboard India's Chandrayaan-1 spacecraft orbiting the Moon has identified thick deposits of water-ice in more than 40 small craters near the Moon's north pole. Ranging from one to 9 miles across, the craters likely contain ice at least a few meters thick, leading to total estimates of at least 600 million metric tons of ice within these craters.
Saturn's largest moon, Titan, continues to show indications of its intriguing surface. NASA's Cassini spacecraft has been in orbit around Saturn since 2004 and recently came across signs of floods, large impacts, and even ice volcanoes under the smoggy atmosphere. Long obscured by thick hazy clouds, Titan is finally revealing its secrets to Cassini.
Astronomers know that in the early universe, small galaxies merge to form larger ones. Observations of distant galaxies are difficult and tricky to decipher. Fortunately a group of galaxies, called the Hickson Compact Group 31, was observed with the Hubble Space Telescope, and astronomers found evidence that these galaxies are just forming, as if they were located in the early universe. The conclusions were confirmed with observations from the Spitzer Infrared Telescope, SWIFT and other observatories. This discovery is akin to finding a dinosaur in our backyard ? we can see the early days up close.
The Sun has a circulation mechanism that brings hot plasma and magnetic fields to its surface. This circulation pattern is called the Sun's Great Circulation Belt. It was thought that sunspots are related to the Sun's circulation, and that the faster the belt ran, the more sunspots there would be. Observations with the Solar and Heliospheric Observatory (SOHO) seem to contradict this model. A new satellite, NASA's Solar Dynamics Observatory, was launched in February 2010, and may be able to discover more through helioseismology, the study of oscillating waves within the Sun.
The Wide-Field Infrared Survey Explorer (WISE), launched by NASA on Dec. 14, 2009, is designed to look at faint objects in the infrared. In February, WISE spotted a new comet as it surveyed the sky. The comet circles the Sun every 4.7 years. WISE needs the public's help to observe the objects it discovers, since the probe won't view them again once they're found. Ground-based observations will help identify the comet's orbit.
A new movie, made up of images taken by the Hubble Space Telescope, provides an unusual view of Saturn with its rings edge-on and practically invisible. It also gives viewers a rare look at the colorful auroras at the planet's north and south poles. This view is available to us only once every 15 years, due to Saturn?s leisurely orbit around the Sun.
The Hubble Space Telescope observed a mysterious X-shaped debris pattern with trailing streamers of dust that suggests a head-on collision between two asteroids -? asteroids that are possible siblings of the one responsible for killing the dinosaurs 65 million years ago.
The Olympic Games of 2010 are making us think about what it would be like to have sporting events on other bodies in the solar system. Mars and the Moon both have ice, for instance. The unusual environments provide challenges and perhaps, in the distant future, some unique opportunities!
One of the most obvious craters on the Moon's surface is relatively young crater called Tycho. "Relatively young" in this case means about 108 million years old, but that's still early enough in the crater's life for it to retain a tremendous system of rays that stretch 900 miles across the lunar surface.
The new Fermi telescope joins a suite of gamma ray telescopes searching for the origins of gamma rays, cosmic rays and evidence of other energetic phenomena in the universe. Fermi has found new evidence for its namesake's theory for the origin of cosmic rays. The idea is that energetic particles are accelerated within the remnants of supernovae. Fermi was able to detect faint gamma-rays that appear to be associated with supernovae in two "normal" type galaxies, M82 and NGC253.
A newly found depression in the Atlantic Ocean floor, south of the Azores Islands, may be an impact crater. It's roughly a circular 3.5-mile-wide hollow with broad central dome and has been dubbed the "Fried Egg" due to its distinctive shape. Scientists will need to investigate further to discover whether the crater was caused by a space impact instead of a volcanic eruption, but the lack of volcanic evidence points to an impact. A second object nearby may be another crater.
The next generation of Moon explorers may end up living in a hole, thanks to the discovery by a Japanese lunar mission of a vertical shaft, probably a collapsed lava tube. Living underground would provide protection from the harsh lunar environment.
The Hubble Space Telescope's Fine Guidance Sensors are targeting devices that lock onto "guide stars" and measure their positions relative to the object under observation, thus helping to point the telescope. But their data is useful for other purposes as well. By digging through 4.5 years of the data from the sensors, astronomers were able to identify the smallest Kuiper Belt Object ever found, locating the object by the dimming of a star as the object passed in front of it.
Five newly discovered planets are among the first results to arrive from NASA's Kepler Mission, launched on Marcy 7, 2009. Kepler was designed to find Earth-size planets. Kepler scientists analyze the light from observed stars, looking for variations. Some light variations are due to processes within the stars themselves, and some are due to "transits" -- that is, a planet passing in front of the star and blocking a tiny bit of the star's light.
Globular cluster Terzan 5, a densely packed group of stars in the Milky Way, is probably the remnants of a long-ago merger between the Milky Way and a dwarf galaxy. Galaxies are known to grow by colliding and merging, combining their stars. Terzan 5 has two different populations of stars, indicating an unusual origin -? globular clusters ordinarily have uniform populations of stars that all formed at the same time from a single cloud of gas and dust.
Incredibly powerful waves of plasma are rippling across the Sun's surface. These "solar tsunamis" were once thought to be an optical illusion. The first witnessed wave, taller than the Earth and creating a rippling pattern millions of kilometers around, was so amazing researchers thought they might be seeing some kind of flaw or trick in the satellite's vision instead of a real wave. The Solar Terrestrial Relations Observatory (STEREO) spacecraft were able to confirm the tsunamis existence.
Brown dwarfs are objects that are bigger than planets but not massive enough to become stars, yet have nuclear reactions in their cores. How do they form? Are they more like planets, or more like stars? A team of astronomers using the Spitzer Space Telescope discovered two objects that appear to be brand-new brown dwarfs. Observatories across the globe are participating in the hunt for new information.
As the International Year of Astronomy draws to a close, a dramatic composite image of the center of our own Milky Way Galaxy was unveiled. The image was a combination of observations from NASA's Great Observatories: Hubble, Spitzer and Chandra. In addition to the composite image, the public can view the individual images obtained by each observatory.