|
|
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.