News Release

Hopkins and Morgan State faculty joined forces with the Applied Physics Laboratory, a Hopkins division, to compete in a NASA-funded program called STEDI, for Student Explorer Demonstration Initiative. Their conceptual design was among the top six selected last month out of 66 proposals. Only two or three of the six satellite designs will be chosen for construction.

Now the pressure is on to quickly assemble a team of students to design the spacecraft within four months, 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. If the design is chosen, the satellite will be launched on a rocket in early 1997 and placed into an Earth orbit. It will be operated for one year.

Faculty advisors 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.

The project will involve about a dozen faculty advisors from the Department of Physics and Astronomy and the G.W.C. Whiting School of Engineering at Hopkins and from Morgan State. A similar number of seasoned staff members at APL will act as mentors to the faculty and students. Marsha Allen, a Hopkins astrophysicist, heads the overall project.

The satellite, conceived by Dr. Henry, is called HRRE (pronounced Harry), for Hydrogen Recombination Radiation Experiment. The 3-foot-long, 30-inch-wide satellite will detect ultraviolet light in an attempt to measure the radiation from hydrogen gas that scientists believe occupies the vast space between galaxies. This primordial 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.

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. Finding the hydrogen gas would be discovering a portion of the sought-after dark matter and, in effect, confirming the existence of the remaining 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.

If their design is chosen, the students will have to craft a new spectrometer based on a design originated by adjunct research professor William G. Fastie of the Hopkins 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 to design HRRE. Students must be able to demonstrate that the satellite's cost won't exceed $4 million, a difficult requirement that can only be met with a detailed engineering design. Perhaps the project's most important result will be to teach students how engineering is done in the real world: by committee, Dr. Pisacane said.

"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 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.