Gamma-Ray Astronomy

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Despite its brilliance, our Sun is something of a weakling. It produces most of its energy as visible light, which is in the middle of the energy scale. But if we could see the sky in the most powerful form of energy -- gamma rays -- the Sun would look dark, because it rarely produces any gamma rays at all. Instead, gamma rays come from some of the most powerful objects and events in the entire universe.

Through gamma-ray eyes, the sky would be ablaze with objects -- some of them inside the galaxy, but many of them far beyond.

Inside the galaxy, we'd see flickering pulsars, which are the spinning corpses of exploded stars. And we'd see a background glow from collisions between particles known as cosmic rays.

Outside the galaxy, we'd see the hot disks of material swirling around black holes in the hearts of galaxies.

And once a day or so, we'd see the brilliant flash of a gamma-ray burst -- an object that would briefly shine brighter than the Sun appears to our "œnormal" vision. Gamma-ray bursts are the most powerful objects in the universe. Some are the flashes of exploding stars. Others may be the final outcries of merging neutron stars, or a neutron star and a black hole.

But the only way to study all these wonders is from outside Earth's atmosphere. A space telescope that's scheduled for launch as early as this month will do just that. We'll have more on the telescope and gamma-ray astronomy throughout the week.

Script by Damond Benningfield, Copyright 2008

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