Next Opportunity: 2011 (two missions)
Scout Mission Funding Cap: $300 million
Out of the four mission proposals for 2007, NASA selected the University of Arizona's Phoenix Lander to be the first Scout mission. The three other finalists may be considered for the future opportunities. They were:
Mars Volcanic Emission and Life Scout (MARVEL)
MARVEL would be an orbiter based on the 2001 Mars Odyssey which would analyse particles in the atmosphere. The orbiter would be in a near-polar orbit, crossing both poles and nearly perpendicular to the equator. It would carry a solar occultation infrared spectrometer to look at light from sunrise/sunsets as it shines through atmospheric particles. The instrument would look for signs of life or hydrothermal activity. The spacecraft could also search for near-surface water and other signs of life with a submillimeter spectrometer.
Aerial Regional-scale Environmental Survey of Mars (ARES)
The Ares mission would fly the first airplane designed to Mars flight. It would be deployed by a capsule entering the atmosphere; the plane would unfold itself once the capsule had reached the proper altitude. Ares would fly at over 300 mph and around 1 km above the ground. Ares would gather data on the composition of the surface and atmosphere, and map the magnetism of the martian surface. It would also examine the isotopic ratios of noble gases including carbon, oxygen, and nitrogen, so that scientists could eventually reconstruct the climactic evolution of Mars.
Sample Collection for Investigation of Mars (SCIM)
The SCIM mission would return the first samples back from Mars. It would "skim" through the atmosphere at around 40 miles from the surface, gathering dust and air samples, then return them back to Earth. The mission calls for two separate passes of Mars, one year apart, to confirm that the area for collection is laden with dust. The spacecraft uses the same type of "aerogel" that was used in the recent Stardust comet sampling mission.
Artemis: This mission would launch up to four saucer-shaped landers, 2 feet in diameter, from a "mother ship" orbiting Mars. Each would parachute onto the surface, analyzing the soil and atmosphere. Two of the four would be targeted at polar regions.
CryoScout: This mission would build a torpedo-shaped probe designed to melt through a polar ice cap using heated jets. It would travel up to 100 yards down, analyzing the melted water to determine the region's conditions.
KittyHawk: This mission would create 3-4 winged gliders with approximately six-foot wingspans and would explore the Valles Marineris canyon system. The gliders would carry infrared spectrometers and cameras.
The Naiades: Named for nymphs of springs, lakes, and rivers from Greek mythology, this mission would send two landers to a region which likely holds groundwater. The landers would search for the groundwater using low-frequency electromagnetics and other instruments.
Pascal: This mission would create 24 tiny weather stations to be landed all across Mars.
Urey: This mission calls for a lander/rover pair designed to analyze the ages of rocks. It would be targeted for the Cerberus Highlands region, and would look for specific minerals to help scientists compare the cratering of Mars with that of the Moon.