After a year
and a half on the Martian surface, the astronauts clamber aboard the Earth Return Vehicle
for their descent into the Earth's atmosphere; a journey projected to be six months
long. In doing so, the astronauts are leaving behind Mars Base 1 containing: the
Beagle hab, a rover, a greenhouse, power and chemical plants, a stockpile of
methane/oxygen fuel, and almost their entire stock of scientific instruments. In May
of 2010, after the first crew has returned to Earth, the second crew will arrive at Mars
in Hab 2 and land at Mars Base 2. The purpose of the second crew revolves around the
premise of exploring the territory around their site, and to drive over to the old Beagle
at Mars Base 1 to further continue their scientific investigations.
The plan is to have two Ares boosters blast off the Cape
every two years; one delivering a hab to a previously prepared site, and the other an
Earth return vehicle to open a new region of Mars to visit by the next mission.
Therefore, two boosters every two years will lead to an average launch rate of just one
launch per year; a 10 percent part of our heavy-lift launch capability to support a
continuing and expanding program of Mars exploration. This is an extremely
efficient, affordable, sustainable system; however, it doesn't end there. These same
Ares launch vehicles, habitats, and Earth return vehicles used in the Mars direct plan can
also be used to build fully functional lunar bases. The question may arise why might
Moon bases be needed to support Mars exploration? Well, they aren't; however, their
value is great for these site for superb astronomical observatories. By using common
transportation hardware for both lunar and Mars exploration, the Mars Direct approach will
save tens of billions of dollars in development costs.
The mission of Mars Direct does not lack any perils at all. The consequences of extended exposure to Mars' gravity, 38 percent that of Earth, are unknown. However, experimentation in orbiting zero-gravity facilities indicates that most of the ill effects are temporary. Next, there is the issue of space radiation which gives the astronauts an additional 0.5 to 1 percent probability of a fatal cancer at some point later in life; however this not much to dwell on considering that those of us who stay home all face a 20 percent risk of fatal cancer anyway.
The
largest risk for failure for Mars Direct arises from possible failures in critical
mechanical or electrical systems. On the other hand, multiple backups for all
important system can minimize the risk, as can the presence of two ace mechanics during
the mission. Going to Mars for the first time will involve a certain level of risk;
however, nothing great has ever been accomplished without risk, nor has nothing great ever
been accomplished without courage.