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Ultraviolet Planet
Photo of earth bathed in colorful ultraviolet lightIt's true what they say about photography: It's all in the lighting. And the vantage point.

Many a photographer has captured the full moon from Earth, but here's a photo of the Earth, bathed in ultraviolet (UV) light, taken from an observatory on the moon.

The image was captured by the Far UV Camera/Spectrograph, which was planted on the moon by the crew of Apollo 16. The part of the Earth that faces the Sun is awash in UV light -- very little of which penetrates the Earth's atmosphere.

Smaller bands of UV light, delivered by the Sun's emission of charged particles, twist along the Earth's magnetic field lines.

The Far UV Camera/Spectrograph uses a three-inch telescope to reveal light at wavelengths between 500 and 1,600 Angstroms (visible light has wavelengths between 4,000 and 7,000 Angstroms).

Instruments that study the invisible realm of UV light are handy tools for astronomers -- after all, the hottest, most dynamic objects in the universe produce gobs of UV energy.

Luckily for UV-sensitive earthlings (what little UV light that reaches the Earth afflicts us with skin cancer), the best place to see UV is from space.

Courtesy NASA .

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