Astronomy is not usually described as "fast paced." Photographing the depths of the universe is usually a business of very long exposures lasting hours or even days.

But a new high-speed camera in the Canary Islands, dubbed ULTRACAM, is poised to change all that by taking up to 1,000 color photographs per second.

ULTRACAM is actually a cluster of large and sensitive digital cameras, jointly developed by scientists at the universities of Sheffield and Southampton in the United Kingdom, and Great Britain's Royal Observatory. Mounted on the biggest optical telescope in Europe, the 4.2-meter William Herschel Telescope on the island of La Palma, ULTRACAM will take aim at the fastest-moving events in the universe.

ULTRACAM is the brainchild of Vik Dhillon of the University of Sheffield, and Tom Marsh of Southampton University.

Their invention comes just as telescopes large enough to gather enough light are becoming more common.

"Using ULTRACAM in conjunction with the current generation of large telescopes means that it is now possible to study high-speed celestial phenomena such as eclipses, oscillations and occultations in stars which are millions of times too faint to see with the naked eye," Dhillon said. "For the first time, astronomers have an instrument specifically designed for the study of high-speed astrophysics."

One of ULTRACAM's main tasks will be "weighing" exotic objects so massive that their weight actually impedes accurate analysis.

Normally, astronomers weigh distant bodies by seeing how strongly their gravity effects their neighbors. For objects like stars, scientists are able to make a good guess at their mass by watching how fast other objects (like companion stars) orbit around them. However, the super-dense corpses of stars -- white dwarfs, neutron stars, and black holes -- don't play very well with others.

"The key feature of objects like neutron stars and black holes is their incredibly small size," said ULTRACAM co-creator Marsh.

"For instance a neutron star packs 1.5 times the mass of the Sun -- some 450,000 times the mass of the Earth -- into an object just 12- 20 kilometers [12-13 miles] across. This means that gas falls onto these objects at great speed and does not take long to do so," Marsh said.

"Standard CCD detectors often cannot even read the data out before material near a neutron star has had the time to orbit it well over 1,000 times," Marsh said. "Its similar to trying to study the wheel of a car in motion by taking an exposure of, say, 10 seconds, during which the car wheel will have revolved several times, compared to taking a high-speed snapshot in which the motion is frozen."

It was to fill this need that Dhillon and Marsh decided to design a new camera.

"ULTRACAM helps us by allowing us to measure the extremely rapid changes," Marsh said.

"The masses of black holes and neutron stars are interesting from two points of view," explained Marsh.

"First, mass is the key parameter of any star and can be used to decide how the star came to be in the first place. It makes a big difference, for example, if a black hole has a mass seven times the Sun compared with, say, 15 times the Sun," he said. That's because a star's mass essentially determines what its life cycle will be like.

"Second, in the case of neutron stars, we don't understand what they are made of too well; it is very extreme," Marsh said. When a very massive star dies but isn't massive enough to create a black hole, it will leave behind a superdense core of material, called a neutron star. While not as well-known as black holes are to the public, neutron stars are almost equally as mysterious.

"Depending upon the exact nature of the material, they can have a different mass, and inversely, their mass can help us determine what they are made of," said Marsh.

ULTRACAM has uses beyond determining the weights and makeup of black holes and neutron stars. There are many briefly flickering astronomical events astronomers are aware of, but haven't been able to observe in detail.

"Similar to black-holes and neutron stars, there are white dwarfs, which are stars about the size of the Earth and similar in mass to the Sun. On white dwarfs, things happen on a time scale of seconds," said Marsh.

"Eclipses of such stars -- when they have close companion stars, as many do -- allow us to measure precise sizes. Again these are not well known but of great importance. These eclipses take about 10 minutes, but the transitions from out-of-eclipse to in-eclipse take only 30 seconds."

Some white dwarfs possess powerful magnetic fields, ranging up to 100 million times stronger than that of Earth. On Earth, the effect of the magnetic poles drawing in the solar wind fuels colorful lights known as auroras. In the same way, the poles of a magnetically potent white dwarf would be powerfully radioactive.

"This (magnetism) forms hot-spots similar in size to Southern England which take only a second or two to be eclipsed," Marsh said. "To understand these exciting regions requires very fast observations."

Even the insides of distant stars may be laid bare by the new camera.

"There are many stars which pulsate, a stellar version of earthquakes. Just as earthquakes have told us about the interior of the Earth, so can these pulsations reveal information about the interior of stars. The pulsations can be quite rapid, and so once again ULTRACAM is useful," said Marsh.

Finally, there are high-speed events happening within our own solar system that would be easier to study with ULTRACAM's freeze frame.

"Nearer to home are lunar and planetary occulations when the Moon or one of the planets passes in front of a bright star. This was how the rings of Uranus and the atmosphere of Pluto were discovered, for instance," Marsh said.

"These events are very rapid. If you look by eye at a lunar occulation, the star appears to go out instantaneously," he said. "In fact it is a gradual transition but too rapid for the eye to see. ULTRACAM is perfect for such observations."