Daily Extra :
Astronomy & Space Word of The Day
tholus: small domical mountain or hill.
Today in History:
1994: Hubble Space Telescope - USA & Europe Telescope photographed the collision of Comet Shoemaker-Levy 9 with Jupiter.
1997: Mars Pathfinder - USA Lander & Surface Rover (December 4, 1996 - September 27, 1997) A six-wheel rover, named Sojourner, rolled onto the Martian surface at about 05:40 UT. Mars Pathfinder arrived at Mars on July 4, 1997 and impacted the surface at 16:57 UT (12:57 PM EDT) at a velocity of about 18 m/s (40 mph). It bounced about 15 meters (50 feet) into the air, bouncing another 15 times and rolling before coming to rest approximately 2.5 minutes after impact and about 1 km from the initial impact site. The landing site was in the Ares Vallis region is at 19.33 N, 33.55 W and was named the Sagan Memorial Station. Mars Pathfinder returned 2.6 billion bits of information, including more than 16,000 images from the lander and 550 images from the rover, as well as more than 15 chemical analyses of rocks and extensive data on winds and other weather factors. The last successful data transmission was on September 27, 1997, the 83rd day of the mission since landing on the surface. This is the second mission in NASA's low-cost Discovery series.
1999: Deep Space 1 (DS1) - USA Asteroid and Comet Flyby - (launched 24 October 1998) flew by the Mars-crossing near-Earth asteroid 9969 Braille. The Deep Space 1 (DS1) is the first of a series of technology demonstration probes being developed by NASA's New Millennium Program. It again flew by comet Borrelly in September 2001.