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Saturn's tiny, icy moon Enceladus has recently been visited by NASA's Cassini orbiter on several very close approaches - once coming within a mere 25 kilometers (15 miles) of the surface. Scientists are learning a great deal about this curious little moon. Only about 500 kilometers wide (310 miles), it is very active, emitting internal heat, churning its surface, and - through cryovolcanism - ejecting masses of microscopic ice particles into Saturnian orbit.

Several decades ago scientists discovered that the Moon, long thought to have no atmosphere, actually does have an extremely thin exosphere.

"One transport truck-sized asteroid passed the Earth Wednesday morning and another will soar by in the afternoon, with both far closer to the planet than the moon. There is no danger of the Earth being hit and both should be visible with moderate-sized amateur telescopes, NASA reported."

NASA's Cassini spacecraft is now a nearly a year into its extended mission, called Cassini Equinox (after its initial 4-year mission ended in June, 2008). The spacecraft continues to operate in good health, returning amazing images of Saturn, its ring system and moons, and providing new information and science on a regular basis.

"View of the solar system showing the locations of all the asteroids starting in 1980, as asteroids are discovered they are added to the map and highlighted white so you can pick out the new ones. The final colour of an asteroids indicates how closely it comes to the inner solar system. Earth Crossers are Red Earth Approachers (Perihelion less than 1.3AU) are Yellow All Others are Green Notice now the pattern of discovery follows the Earth around its orbit, most discoveries are made in the region directly opposite the Sun. You'll also notice some clusters of discoveries on the line between Earth and Jupiter, these are the result of surveys looking for Jovian moons. Similar clusters of discoveries can be tied to the other outer planets, but those are not visible in this video. As the video moves into the mid 1990's we see much higher discovery rates as automated sky scanning systems come online. Most of the surveys are imaging the sky directly opposite the sun and you'll see a region of high discovery rates aligned in this manner. At the beginning of 2010 a new discovery pattern becomes evident, with discovery zones in a line perpendicular to the Sun-Earth vector. These new observations are the result of the WISE (Widefield Infrared Survey Explorer) which is a space mission that's tasked with imaging the entire sky in infrared wavelengths. Currently we have observed over half a million minor planets, and the discovery rates snow no sign that we're running out of undiscovered objects. Orbital elements were taken from the 'astorb.dat' data created by Ted Bowell and associates at http://www.naic.edu/~nolan/astorb.html"

Winter Solstice - Total Lunar Eclipse 2010 - TIME-LAPSE Total eclipse on winter solstice. 4.5 hours shortened to a minute and thirty seconds.