From our current vantage point, massive black holes appear a guarded but unmistakably hungry bunch. Though we cant exactly see them, we know they gobble up mass at incredible rates, making meals of any matter that dares to move in for a closer look.

But soon, a duo of powerful new NASA telescopes may change our view of distant black holes forever. With an ultimate resolution of more than 3 million times better than that of the Chandra X-ray Telescope, the new observatories should allow astronomers to finally peer into the dense black holes that are thought to exist at the center of many galaxies.

The telescopes are being developed by the University of Colorado (UC) at Boulder and NASA, and are part of the Microarcsecond X-ray Imaging Mission, or MAXIM for short. According to project leader and UC professor Webster Cash, MAXIM should give astronomers an extremely closeup view of black holes, objects whose existence we can currently only infer.

Black holes are regions of space so dense, not even light can escape their gravitational grasp. But black holes are invisible with current technology because they are tiny compared to the visible cores of their host galaxies. While a galactic core may span about 200 light-years across, a black hole is only about one-three-thousandth of a light-year across, roughly the same size as our solar system.

Truth be told, no one can actually see a black hole since by definition its an invisible region of space. However, black holes are surrounded by large disks of matter and energy that shine brightly. It is these disks that astronomers hope to image in great detail with the MAXIM project telescopes.

Theory holds that if a telescope can get good enough resolution to see the very center of an accretion disk, astronomers may be able to witness a black holes event horizon, the circular black "dot" that marks the boundary point beyond which brightly shining matter falls into a black hole. According to Cash, being able to capture images of a black holes event horizon would help astronomers "understand what controls the flow of material into the hole."

To get such close resolution, Cash and his colleagues have proposed the construction of two space-based X-ray interferometers, observatories that combine information from a number of mirrors to create one very detailed image.

"A visible-light telescope with the resolution of this newly designed X-ray telescope could be used to count the hairs on an astronaut's head while she was standing on the moon."

The first planned interferometer, called MAXIM Pathfinder, would be a prototype tester spacecraft containing two mirrors and a detector instrument to add up X-rays gathered by the two mirrors. Though the Pathfinder wouldnt quite have the resolution to image a black hole, it would allow astronomers to test out innovative X-ray interferometery methods, which would then be employed on the second and more ambitious MAXIM telescope. While no firm deadline has been reported, NASA has tentatively scheduled the MAXIM Pathfinder to launch in or near 2011, with the follow-up MAXIM mission taking flight in 2016.

The main MAXIM scope would be comprised of a fleet of 33 spacecraft, each containing a relatively small telescope. A larger detector spacecraft, which would collect and combine the data from the smaller telescopes, would fly about 300 miles (485 kilometers) behind the 33 smaller spacecraft. Such a configuration, while inherently complex, would allow astronomers to achieve the best-yet resolution of cosmic objects including black-hole-containing galaxies.

"A visible-light telescope with the resolution of this newly designed X-ray telescope could be used to count the hairs on an astronauts head while she was standing on the moon," said Cash.

"Apart from satisfying our curiosity as to what the region surrounding a black hole looks like, this advance will allow us to directly observe effects predicted by Einsteins theory of general relativity under the most extreme gravity fields known," added Nicholas White, a researcher at NASAs Laboratory for High Energy Astrophysics in Greenbelt, Maryland.

In addition to helping astronomers monitor how matter ends up falling into a black hole, astronomers hope MAXIM will answer several other black hole mysteries as well. These include just how strong the gravitational pull at the center of a black hole is, and how the gas jets that are often found protruding from black holes are formed.

While many hurdles remain, Cash and his colleagues seem generally optimistic that the MAXIM project will be adopted by NASA for launch in the next 10 to 15 years. As engineers already know from building the Chandra X-ray Observatory, space interferometers are difficult to piece together. But although MAXIM is an extremely ambitious mission, Cash said that engineers are already working hard to develop the easiest possible method to get the observatory up and running.

"We have a large, demanding mission on the one hand," said Cash, "but new high-tech techniques to balance those demands on the other."