August 30, 2010

NAS names JHU projects astrophysics priorities

Report: ‘New Worlds, New Horizons’ represents consensus of experts

A report released by the National Academy of Sciences names several projects involving astronomers and astrophysicists at The Johns Hopkins University as among the most important astrophysics investments in the next decade.

Titled “New Worlds, New Horizons in Astronomy and Astrophysics,” the recently issued report represents the consensus position of hundreds of astronomers and astrophysicists nationwide who participated in the process of prioritizing projects.

Topping the list in the space missions category is the Wide-Field InfraRed Survey Telescope, which is aimed at learning more about the accelerating expansion of our universe, searching for planets outside our solar system and exploring how galaxies form and evolve over time. WFIRST is partially based on research led by Adam Riess, the Krieger School of Arts and Sciences astrophysicist whose team reported in 1998 that the expansion of the universe was accelerating, due to a still mysterious force known as “dark energy.”

The WFIRST mission’s hardware design has its roots in the Joint Dark Energy Mission, on which Johns Hopkins astrophysicist Charles L. Bennett has served in various capacities. Bennett, who recently won the Shaw Prize in astronomy for his groundbreaking work in determining the age, shape and composition of the universe, served as co-chair of the JDEM Science Definition Team, was a member of the JDEM Science Coordination Group and led a team that designed a detailed mission approach. In fact, the hardware design recommended by the National Academy of Sciences report closely resembles the Bennett team’s mission design, which was the result of collaboration between scientists at Johns Hopkins and other universities, and scientists and engineers at NASA’s Goddard Space Flight Center.

“We designed a mission that could conduct a wide-field infrared survey of the sky while also measuring the three-dimensional position in space of 200 million galaxies to learn about their evolution, and to trace the history of the accelerated expansion of the universe,” said Bennett, a professor in the Krieger School’s Henry A. Rowland Department of Physics and Astronomy. “We are very pleased that our approach was adopted by the JDEM Project Office at Goddard, and was strongly endorsed by the entire community through this very influential consensus report.”

Warren Moos, also a professor in Physics and Astronomy and a member of Bennett’s JDEM design team, co-chairs the JDEM Interim Science Working Group, which was formed in December 2009 to guide NASA.

First place among the ground-based observatories in the new report was the Large Synoptic Survey Telescope, a wide-field survey instrument to be located on the El Penon peak of Cerro Pachon in northeast Chile and on which construction will begin this year. Johns Hopkins is currently a partner on this developing project, which will rapidly survey large swaths of the sky repeatedly over time. In fact, Johns Hopkins astronomers are already involved in a precursor effort called Pan-STARRS, which is observing the sky in a similar manner from Hawaii. LSST promises to take Pan-STARRS science to a new level.

Both WFIRST and LSST promise to produce immense amounts of data that will be mined for information, according to Alexander Szalay, director of Johns Hopkins’ Institute for Data-Intensive Engineering and Science.

“WFIRST and LSST are exemplars of the emerging field of data-intensive science that is made possible by the rapid growth of computer power, and are part of a movement that is transforming the very essence of how scientific discovery and engineering research are being done and will happen now and in the future,” Szalay said. “Researchers can now do science directly within databases, teasing out relationships that are not evident at first glance.”

Ranked second in the space category of the National Academy of Sciences report is an expansion of NASA’s Explorer line of missions. Bennett is the leader of the Wilkinson Microwave Anisotropy Probe Explorer mission, and Moos led the earlier Far Ultraviolet Spectroscopic Explorer mission.

“We are delighted to hear about the proposed expansion of the Explorer program,” Moos said. “Johns Hopkins has the demonstrated capability to compete in this mission category, so this is great news for us.”

Ranked second in the report’s ground-based astronomy category was midscale instrument development, which is good news for the Johns Hopkins scientific initiatives that make use of the Instrument Development Group. The IDG designs hardware for a variety of aerospace and ground-based projects.

The “New Worlds, New Horizons” report, which also strongly endorsed the ground-based search for cosmic microwave background signals from the universe’s earliest moments, called for an increase in investments in this research area. In March, Bennett was awarded a National Science Foundation grant to build an instrument designed to probe what happened during the universe’s first trillionth of a second, when it suddenly grew from submicroscopic to astronomical size in far less time than it takes to blink an eye. Called the Cosmology Large Angular Scale Surveyor, or CLASS, the instrument is expected to require five years to build and will have the capability to measure the “cosmic microwave background radiation” over large swaths of the sky.

Johns Hopkins astronomers also are eagerly awaiting the launch of the James Webb Space Telescope, sometimes referred to as the “next generation Hubble Space Telescope.” The instrument’s science center will be headquartered at the Space Telescope Science Institute, located on Johns Hopkins’ Homewood campus. According to Bennett, the James Webb’s very deep and narrow view will complement the wide and shallow infrared focus of WFIRST, providing a very powerful scientific “one-two punch.”

Katherine S. Newman, who assumes her post as dean of the Krieger School on Sept. 1, said she is enthusiastic about the National Academy report’s acknowledgment of the work being done in the Department of Physics and Astronomy.

“I am delighted that the National Academy survey recognizes the outstanding research program of my colleagues in Physics and Astronomy,” Newman said. “Johns Hopkins is fortunate to have such remarkable leadership. They are national treasures in this critical field.”