A Johns Hopkins astrophysicist is the principal researcher on a proposal, accepted this week by NASA, to design a space mission to determine the properties of the mysterious dark energy is causing the expansion of the universe to speed up.
The Advanced Dark Energy Physics Telescope mission promises to determine the location of 100 million galaxies in the most comprehensive survey of the universe ever taken, said Charles Bennett, professor in the Henry A. Rowland Department of Physics and Astronomy at the Krieger School of Arts and Sciences. In addition, ADEPT promises to discover about 1,000 new supernovae.
“We are delighted the [NASA] reviewers recognized that the ADEPT approach is important and very powerful,” Bennett said. “It is based on experimental breakthroughs that have occurred in just the last three years. ? We believe that ADEPT?s results are likely to be of extraordinary importance to science.”
Dark energy is the term used to describe a new form of energy Bennet believes permeates all of space. Unlike gravity, which pulls bodies together, dark energy is a repulsive, or outward-pushing force.
This energy has never been seen directly, and its composition remains unknown, Bennett said.
“Is the physical nature of dark energy constant, or does it evolve with time? To answer this question, we must look back in time, and for astronomers, that means looking at distant objects,” Bennett explains.
The original discoverer of dark energy, Hopkins professor Adam Riess, made his discovery by observing a special kind of exploding star, or supernova. Riess said the color signature of these supernovae shifts toward red as they speed away from us in space. The further away ? and therefore the older ? the supernovae, the slower they are moving, he said. This means the expansion of the universe is getting faster.
The NASA Goddard Space Flight Center in Greenbelt, with its science and engineering expertise, will be Johns Hopkins? partner on ADEPT.
