RELEASE: 06-254
NASA'S MICRO-SATELLITES COMPLETE TECHNOLOGY VALIDATION MISSION
NASA's three orbiting micro-satellites known as Space Technology 5
have completed their planned 90-day mission. The mission team is
shutting down the spacecraft to conclude operations on Friday, June
30.
The mission primarily focused on flight testing miniaturized
satellites in the harsh environment of space and evaluating their
ability to make research-quality scientific measurements.
The satellites were launched on March 22. Each fully fueled satellite
weighed approximately 55 pounds when launched and is about the size
of a 13-inch television.
A major milestone of the mission was reached when the spacecraft
assumed a constellation formation on May 24. The satellites lined up
in nearly identical orbits, like three pearls on a necklace,
approximately 220 miles apart. Reaching formation required seven
maneuvers using miniaturized micro-thrusters. Each spacecraft has a
single micro-thruster the size of a quarter to perform both attitude-
and orbit-adjustment maneuvers.
The mission demonstrated the benefits of using a constellation of
spacecraft to perform scientific studies of the beautiful auroral
displays that occur near Earth's polar regions. The spacecraft
simultaneously traversed electric current sheets and measured the
magnetic field using miniature magnetometers.
"Taking measurements at the same time in different locations allowed
scientists to better estimate the thickness of current sheets and how
they vary over time," said Guan Le, mission project scientist at
NASA's Goddard Space Flight Center, Greenbelt, Md. "This could not
have been done with a single spacecraft, no matter how capable."
The mission validation team demonstrated the sensitivity of miniature
magnetometers, and suitability of the satellites for supporting
scientific measurements. Over the next few months, the team will
process the mission's magnetometer data, complete its assessments of
the performance of the satellite constellation and report initial
findings.
The mission also demonstrated an innovative communications technology.
The satellites used miniature spacecraft radio transponders for
space-to-ground communications and tracking. The transponders were
coupled with conventional and computer-optimized or -evolved
antennas. The transponders and antennas performed flawlessly.
The satellites' miniature power system demonstrated a high level of
performance. All spacecraft lithium ion batteries stayed above 90
percent charge, even during some tests intentionally designed to use
them. The high-efficiency solar arrays on all three spacecraft
produced more power than predicted prior to launch, and their
batteries performed to expectations.
During the final days of the mission, the emphasis was on
demonstrating ground system technologies. The ground system is highly
automated to reduce the cost of operating multiple spacecraft as a
single constellation rather than operating them individually. This
type of ground system will help pave the way for an affordable means
of simultaneously flying from 10 to hundreds of micro-satellites.
The project was developed and tested at Goddard. It is part of the New
Millennium Program, which develops and tests high-payoff technologies
that provide future science mission capabilities with reduced cost
and risk. Each flight acts as a test track for competitively-selected
technologies, mission objectives and operations concepts. New
Millennium is managed for NASA by the agency's Jet Propulsion
Laboratory, Pasadena, Calif.
For information about the Space Technology 5 mission's technology and
detailed results, visit:
http://www.nasa.gov/st5
