In September 1997, the spacecraft will fall into orbit around Mars by “aerobraking,” using friction with the planet’s atmosphere to decelerate. It will scan the surface and take atmospheric measurements for a MArtian replace six of the eight lost on the Mars Observer in 1996.
The craft will enter the Martian atmosphere on July 4, 1997, and float down onto an ancient flood plain. It will photograph the Martian terrain in 13 different colors and deploy a small rover to explore the region around the lander. The primary goal is to demonstrate a low-cost, soft landing.
The craft will orbit Mars after an 11-month voyage and deposit two landers to relay measurements through the Global Surveyor. Also, two penetrators dropped from the orbitor will burrow underneath the surface to analyze the soil.
NASA will send a separate orbitor and lander on Med-lite rockets, which cost and carry less than the Delta II. The lander will be ther first ever sent to the icy south pole, where a robotic arm will dig trenches in the soil while a camera snaps the layers underneath.
The possibilities for 2001 are still being evaluated. Many scientists advocate sending an orbiter with a high-resolution spectrograph, a camera capable of identifying small-scale mineralogical details of hydrothermal springs and vents that could harbor fossils.
The orbiter will conduct experiments in the Martian atmosphere and observe its interaction with solar wind. A U.S.-supplied spectrometer will measure the composition of the upper Japan’s 1998 mission atmosphere.
If data from the 2001 mission is returned in time, the first in a series of robotic sample-return missions could launch as early as 2003. A lander would deploy a robotic rover to collect geologic samples and a return rocket would bring the samples back to Earth.
If evidence of Martian life is confirmed in Earth labs, humans, would have to go looking for fossils. The mission might also begin the process of colonizing Mars. That could happen as soon as 2008, but would face several formidable barriers:
Even with vigorous exercise, prolonged weightlessness on the way can cause cardiovascular and muscular deterioration.
Mars has no food or water and experiences fierce dust storms.
A spacecraft carrying all the fuel necessary to get there and back would be expensive and heavy. But a manned lander could meet a return vehicle on the planet, sent earlier to manufacture fuel from the atmosphere.
