SpaceDev subsidiary, Starsys, Inc., has completed a 3.5 million cycle life test on the actuator system for the Mars Climate Sounder (MCS), an instrument on the Mars Reconnaissance Orbiter (MRO). The testing validated the ability to run the actuator for over two times the full life of the primary mission and demonstrated a capability that far surpasses previous NASA flight experience with this type of space flight mechanism.

“We are proud to be a part of this exploration mission and the push to further understand the Martian atmosphere and weather,” said Mark Sirangelo, Vice Chairman and Chief Executive Officer of SpaceDev. “As part of the instrument suite on the MRO, the MCS views from orbit the horizon of Mars to observe the atmosphere in vertical slices, with measurements every five kilometers (three miles) down through the atmosphere.”

These measurement “profiles” are combined into twice-daily, three-dimensional global weather maps — one for daytime and one for nighttime. The maps display temperature, pressure, humidity and dust at each five-kilometer layer of the atmosphere: the same type of information meteorologists use to understand and predict weather and climate on Earth. Starsys’ actuators will be used to point the MCS instrument so that it can accurately measure each altitude slice as it orbits the planet. The data will be used to understand how the Martian atmosphere circulates and alters over time. The measurements are also expected to help explain how and why the Martian polar caps vary in relation to changes in the atmosphere and the energy output from the sun.

“Long-life spacecraft mechanisms are challenging due to the nuances of actuator lubrication in a vacuum environment,” said Robert Vacek, Starsys’ President and General Manager. “The flight actuator system for MCS will provide key capabilities for NASA to perform their science mission, and the demonstrated long-life may enable an extended mission on this and future NASA programs.”

Starsys completed the testing of its actuator system — as well as the delivery of two flight actuators — under contract to the Jet Propulsion Laboratory/California Institute of Technology (JPL) in Pasadena, California. The actuators are part of the MRO system currently in orbit around Mars. They are operating as expected, and data collection from the MCS is scheduled to begin in late 2006.

About SpaceDev

SpaceDev (OTCBB: SPDV – News) creates and sells affordable and innovative space products and solutions to government and commercial enterprises. SpaceDev’s innovations include the design, manufacture, marketing and operation of sophisticated micro- and nano-satellites, hybrid rocket-based orbital Maneuvering and orbital Transfer Vehicles as well as sub-orbital and orbital hybrid rocket-based propulsion systems for safe human space flight. In addition, Starsys, Inc., a wholly-owned subsidiary of SpaceDev, is engaged in the design and manufacture of mechanical and electromechanical subsystems and components for spacecraft. Starsys’ subsystems enable critical spacecraft functions such as pointing solar arrays and communication antennas and restraining, deploying and actuating of moving spacecraft components. For more information, visit www.spacedev.com and www.starsys.com.

Except for the factual statements made herein, the information contained in this news release consists of forward-looking statements that involve risks, uncertainties and assumptions that are difficult to predict. Words and expressions reflecting optimism and satisfaction with current prospects, as well as words such as “believe,” “intends,” “expects,” “plans,” “anticipates” and variations thereof, identify forward-looking statements, although their absence does not mean that a statement is not forward looking. Forward-looking statements are based on the Company’s current expectations. Such forward-looking statements are not guarantees of performance, and the Company’s actual results could differ materially from the Company’s current expectations based on many factors that are directly or indirectly related to the items discussed above. Factors directly related to the subject of this release that could cause or contribute to such differences include risks and uncertainties associated with the Company’s acquisition of Starsys Research Corporation, including (i) the Company’s ability to effectively integrate operations and effectively execute the business plan, (ii) any loss of a major customer or rescheduling or cancellation of customer orders, (iii) the uncertainties in the government budgeting process, (iv) the combined company’s ability to control costs and expenses, (vi) the possibility of further cost overruns on fixed-price contracts, and (vii) the need for additional financing to support the combined business. Reference is also made to other factors set forth in the Company’s periodic reports filed with the Securities and Exchange Commission, including “Management’s Discussion and Analysis” and other sections of the Company’s most current Annual Report on Form 10-KSB and subsequent Quarterly Reports on Form 10-QSB. These forward-looking statements speak only as of the date of this release, and the Company undertakes no obligation to update publicly any forward-looking statements to reflect new information, events or circumstances after the date of this release.

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