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Complementing the facility-class Einstein Great Observatories will be three sharply focused missions, each addressing a specific science question. These missions will all be selected through an open competition.
 | | The WMAP result on dark energy and cosmology was hailed as the top scientific breakthrough of 2003 by Science magazine.(Cover image reprinted with permission from AAAS.) |
In the past decade scientists have come to realize that normal matter and dark matter comprise only 26% of the Universe’s total mass-energy budget. Something else, dubbed "dark energy," comprises the remaining 74%—and it's causing cosmic expansion to accelerate. The nature of dark energy is one of the most vexing mysteries of our time. Scientists have proposed a number of ideas about what it might be, but we need more data to tell which theories can be discarded, and which ones might have a kernel of truth.
The Joint Dark Energy Mission (JDEM) will address the question "What is the mysterious energy pulling the Universe apart?" JDEM is an interagency partnership between NASA and the Department of Energy to develop a mission that will study dark energy and determine how it evolves with time.
The early Universe appears to have undergone a brief period of "inflation," when it expanded so rapidly that certain regions separated from other regions faster than the speed of light. This exponential expansion enabled slight density differences in an incredibly dense young universe to ultimately grow into the stars, galaxies, and enormous voids we see today. What energy or force field propelled this inflation? Is it the same force that is accelerating the expansion of the Universe today?
Three mission concepts have been proposed for the Beyond Einstein "Einstein Inflation Probe," and all will investigate the question these great mysteries about inflation, which tie directly to an even deeper question: "How did Our Universe begin?"
Astronomers have identified two major classes of black holes: small black holes that form from the collapse of massive stars; and supermassive monsters in the cores of large galaxies. The latter contain the mass of millions to billions of Suns and grow by swallowing stars and gas that venture too close, and from the mergers of central black holes when their host galaxies collide.
These processes release huge amounts of energy. But there is an accounting problem: Not enough light is coming from supermassive black holes to explain how they have accumulated such immense sizes. Astronomical observations suggest that much of their growth occurs behind a shroud of dust. Two mission concepts have been proposed for the "Black Hole Finder Probe," which will conduct a census of hidden black holes, revealing where, when, and how they form.
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