Viking 2's 30th!

Figure 1	Figure 2

3 September 2006
Viking 2 landed 30 years ago today, on 3 September 1976. It was the second of the two Viking landings on Mars. Viking 1 touched down on 20 July 1976. Since the Viking missions of the 1970s, only 3 additional spacecraft have successfully landed and conducted their scientific investigations: Mars Pathfinder (1997), Mars Exploration Rover Spirit (2004-present), and Mars Exploration Rover Opportunity (2004-present). Two new U.S. Mars landed missions are currently in the works: Phoenix, launching in August 2007, and MSL (Mars Science Laboratory), launching in 2009.

As with the 30th anniversary of the Viking 1 landing in July (see PIA08616), for the Viking 2 30th anniversary, we show here the best Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) view of the landing site.

On that day 30 years ago, Viking 2 landed in Utopia Planitia, west of Mie Crater, near 48.0°N, 225.7°W. At the time, it was considered that this might be a good place to look for evidence of life in the martian regolith. This middle north latitude site is often obscured by clouds in the winter and dust hazes in the spring. The surface was observed by the lander to be dusted by thin coatings of frost during the winter months.

The exact location of the Viking 2 lander was uncertain until MOC obtained the high resolution view, shown above, in 2004. These images were previously released by the MOC team on 5 May 2005, along with what was then considered to be the best candidate for the Mars Polar Lander site (see "MGS Finds Viking 2 Lander and Mars Polar Lander (Maybe)"). The candidate Polar Lander site was further imaged in 2005 and found not to be the lander (see PIA03044).

Figure 1 shows (A) a mosaic of Viking Orbiter images obtained in the 1970s at a resolution of 75 m/pixel, (B) a typical MGS MOC narrow angle camera view at about 3 meters/pixel (25x higher resolution than the Viking images), and (C, D) sections of a MOC image obtained at ~0.5 m/pixel. Figure 2 shows an extreme enlargement of the feature identified as Viking Lander 2, compared to a schematic drawing of the lander in the orientation determined during the Viking mission.