Pure Oxygen To Be Produced From Martian CO2
University Science http://unisci.com
For the first time, a system will produce a valuable byproduct from an
extraterrestrial source. In January 2002, that system will suck in Martian
atmospheric gases -- predominately carbon dioxide -- and process them to
produce pure oxygen.
This could be seen as the space exploration equivalent of standing on the
brink of the Industrial Revolution, but with a gigantic resource base --
all the materials found on planets, their satellites, and asteroids in the
Professor K.R. Sridhar and his 20-member team at The University of Arizona
Aerospace and Mechanical Engineering (AME) Department are now building that
system, which they call an Oxygen Generating Subsystem (OGS).
"This is a landmark experiment," Sridhar says. "It is the first time in
human history that we will produce a consumable of use to humans from
The oxygen could be used as a propellant in rocket motors or for life
support for humans on Mars. (Since this is a demonstration experiment, the
oxygen will not be put to immediate use on the Mars Surveyor 2001 lander.)
But Sridhar hopes to have an experiment aboard the Mars Surveyor 2003
mission that will produce both fuel and oxygen from Martian resources. In
that case, the oxygen and fuel would be used to launch a small rocket from
the surface of Mars or to power a drill that would take core samples of the
"In the larger scheme of things, in 2007 we hope to perform a sample return
mission that will rely on the propellant production technology we are
developing to produce both the fuel and oxygen for a rocket to bring the
sample back to Earth," Sridhar says. "We are working very vigorously on
The OGS will fly to Mars aboard Mars Surveyor 2001, which is scheduled to
land on the Red Planet on Jan. 22, 2002.
Once on Mars, it will use solid oxide electrolysis to produce oxygen. The
technology is based on an electrochemical cell that works as a solid state
filter for oxygen. The electrolyte used in the OGS will transfer only
oxygen ions across its crystal structure.
The unit weighs about two pounds and will consume less than 15 watts of
electrical power to produce more than one cubic centimeter of oxygen per
minute. This is twice the amount NASA specified in its contractual
requirements for the oxygen generator.
"The challenges were to miniaturize the technology and to make the process
very energy efficient, while producing a device that is rugged enough to
withstand launch loads up to 35 Gs (35 times the force of gravity at sea
level)," Sridhar says.
The space-qualified OGS is being built entirely in the UA AME Space
Technologies Laboratory, where Program Manager Matthias Gottmann is
supervising a team made up of staff engineers, graduate students,
undergraduates, postdocs, and exchange students.
OGS construction includes producing ceramic heating elements from scratch
that heat up faster and go to higher temperatures than commercially
available elements now do.
Producing resources in situ has many advantages, Sridhar explains. "By
using extraterrestrial resources, you lower the launch mass from Earth and
thereby reduce the cost. You also reduce the overall risk of a mission
because you can produce safety caches of valuable consumables that will be
available to humans at the destination."
But, he adds, perhaps the most significant aspect of in situ resource
utilization is that it is the enabling technology that will make possible
permanent settlements on other planets and their satellites.
Photos of the Oxygen Generating Subsystem can be viewed online at