Share your thoughts about SkyWatch.
September 25, 2008
Show 183: Venus Rising
The planet Venus is now visible very low in western sky right after sundown. This evening appearance of Venus will become even better in coming weeks as the planet rises higher and higher each night throughout the fall and winter. The brilliant “evening star” will be at its brightest on Feb. 19.
September 18, 2008
Show 182: Stellar Streams
The Milky Way galaxy is part of a group of galaxies, including several small “dwarf galaxies,” that interact with one another. The outer portion of the Milky Way, called its “halo,” is filled with clouds of gas, star clusters, dark matter and streams of stars gathered from those dwarf galaxies by the power of the Milky Way’s gravity. The Sloan Digital Sky Survey (SDSS) revealed these multiple, previously unknown streams.
September 11, 2008
Show 181: Clusters in a Cluster
About 54 million light-years from Earth, roughly 2,000 galaxies have ganged up in a gravitational grouping called the Virgo Cluster. Centering that cluster is a massive galaxy that is itself surrounded by many clusters-in this case, star clusters. But this massive galaxy has more of these star clusters than astronomers expected it to have. Could it be stealing from its neighbors?
September 4, 2008
Show 180: Hubble Hits 100,000 Orbits
In August, the Hubble Space Telescope completed its 100,000th orbit around Earth. Understandably, the venerable observatory is due for a little maintenance. In October, astronauts will be returning to Hubble to install two new science instruments, repair two other instruments, and upgrade other critical components on the telescope.
August 28, 2008
Show 179: HubbleWatch for August 2008
Hubble celebrated a new milestone in August – 100,000 orbits around the planet Earth. Scientists think they know why a certain galaxy has more globular clusters than its neighbors. And a black hole-inhabited galaxy is sending tendrils into the universe.
August 28, 2008
Show 178: Cassini and the Jets
The Cassini spacecraft performed a daring flyby of Saturn’s moon Enceladus on March 12, flying about 15 kilometers per second (32,000 mph) through a geyser-like jet spurting from the moon’s surface. It captured sample molecules from the jet.
In August, it used special techniques to get pictures of the jets. Scientists want to know where the jets come from and whether Enceladus has water.
August 21, 2008
Show 177: Water from a Rock
Could Earth’s Moon have water locked up inside its rocks? Samples brought back from the Apollo Moon mission may indicate that the answer is yes. Water may be locked up in volcanic glass beads within the rocks.
August 14, 2008
Show 176: Giant Lurks in Kuiper Belt?
The Kuiper Belt is a region past Neptune, full of icy, comet-like objects. Pluto is the most famous Kuiper Belt object. Some of these objects have odd orbits that don’t fit with our knowledge of the solar system. A computer model suggests that the region may contain a really large body — 30 to 70 percent as massive as Earth — that affects the orbits of objects around it.
