Student Spacecraft Design May Prove 'Big Bang' Concept By Emil enere Students at Hopkins and Morgan State universities are jointly designing a spacecraft to search for the mysterious "dark matter" many theorists believe makes up most of the universe. The quest is a bold one, since it involves the nearly impossible task of detecting ionized hydrogen gas. But if it succeeds it will be a scientific landmark supporting the Big Bang concept of cosmic creation. Faculty at the Homewood campus, the Applied Physics Laboratory and Morgan State joined forces to compete in the NASA-funded program Student Explorer Demonstration Initiative, or STEDI. Their conceptual design was among the top six selected last month out of 66 proposals. But only two or three of the designs will be chosen for actual construction. The pressure is on to assemble quickly a team of students to design the spacecraft within a four-month deadline, a tough assignment even for a staff of professional engineers, said Vincent Pisacane, assistant director for research and exploratory development at APL. "With inexperienced students it's going to be a challenge to make the deadline," Dr. Pisacane said. Faculty advisers will recruit about 30 undergraduate and graduate students from Hopkins and six from Morgan State, said Hopkins astrophysicist Richard C. Henry, director of the Maryland Space Grant Consortium, a NASA-affiliated organization that promotes science education and sponsored the spacecraft proposal. Electrical engineering professor Charles Westgate will lead the spacecraft team on the Homewood campus. Marsha Allen, an associate research scientist in the Department of Physics and Astronomy, heads the overall project. "We are confident our students can meet the challenge and produce a successful spacecraft," Dr. Westgate said. The satellite, Hydrogen Recombination Radiation Experiment, was conceived by Dr. Henry. Scientists refer to the project as Harry, for HRRE. The 3-foot-long, 30-inch-wide satellite will not see optical light that is visible to the human eye. It will detect invisible ultraviolet emissions in an attempt to measure the radiation from hydrogen gas that scientists believe occupies the vast space between galaxies. The hydrogen, which has not yet been proven to exist, represents the ashes left over from the Big Bang that many cosmologists believe marked the birth of the universe 15 billion to 20 billion years ago. Finding the gas would, in effect, be discovering the sought-after dark matter. But detecting ionized hydrogen is a remote possibility, since its atoms have been stripped of their single electrons from bombardment with radiation, so the hydrogen will not absorb light passing through it and it leaves no tell-tale signature when viewed through a spectrograph. However, ionized hydrogen can capture free electrons, causing a "recombination" of hydrogen atoms. HRRE will look for the ultraviolet radiation produced when ionized hydrogen recombines. The satellite builders will have to craft a new spectrograph, based on a design originated by adjunct research professor William G. Fastie, in the Department of Physics and Astronomy. The existence of dark matter has been inferred for two decades, according to theories and observations that support the idea that the universe contains far more matter than has been directly observed using current technology. Astronomers think that at least 90 percent of the mass in the universe has not yet been detected. Instruments sensitive to ultraviolet radiation must be placed above the Earth's atmosphere, which blocks most ultraviolet light. While some ultraviolet instruments have found sketchy evidence for the primordial hydrogen, no instruments now in operation have been designed specifically for that purpose, Dr. Henry said. "The fragmentary observations that exist are very poor in quality," said Dr. Henry, an expert on "interstellar medium," the debris found between stars. "We are going to make the measurements in a definitive way." The Hopkins-Morgan State team has received $160,000 from NASA to design HRRE. Students must be able to demonstrate that the satellite's cost will not exceed $4 million, a difficult requirement that can only be met with a detailed engineering design, said Dr. Pisacane. Perhaps the project's most important result will be to teach students how engineering is done in the real world--by committee. "It's an excellent engineering learning experience that one rarely gets in undergraduate education, even in graduate education," Dr. Pisacane said. "When you leave academia you are rarely working alone. Generally, if you are working on a small team, it's part of a larger team. You have to design and build something that satisfies many different criteria. The learning experience for the students will be in making compromises to develop a product for a competitive price in a reasonable amount of time." The Hopkins-Morgan State students will have an edge, with APL on their team. "No other university has built more than 50 spacecraft," Dr. Pisacane said. "We are probably the premier builder of small spacecraft in the world." Morgan State also brings some space experience to the team. Scientists there recently designed an instrument that tested how the space shuttle reacted to stresses when thrusters were ignited, said Ernest C. Hammond Jr., an assistant professor of physics at Morgan State. The project will involve about a dozen faculty advisers from the Department of Physics and Astronomy, the G.W.C. Whiting School of Engineering and Morgan State. A similar number of staff members at APL will act as mentors to the faculty and students. Not all students on the team will need engineering strengths. A variety of skills is necessary to administer space projects, Dr. Henry said. Those interested in joining the project may contact Dr. Allen at 516-6561. The STEDI program is managed for NASA by the Universities Space Research Association, a group of universities that promotes space science and technology. The five other teams competing for the satellite program are from the University of Michigan, University of New Hampshire, Boston University and the University of Colorado, which has two separate satellite proposals.
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