Object Gallery

Messier objects, full set

Messier objects. These 110 astronomical objects were catalogued by the French astronomer Charles Messier (1730-1817), a comet hunter who wanted to list the permanent objects in the sky that might be mistaken for comets. They range from the Crab nebula (M1) at top left to the dwarf elliptical galaxy M110 at bottom right. Other notable Messier objects include the Orion nebula (M42, upper left), the Ring nebula (M57, centre right) and the Whirlpool galaxy (M51, centre left edge). Trying to observe all 110 objects in one night is known as the Messier Marathon. This is easiest to accomplish in the spring in the Northern Hemisphere

© SCIENCE PHOTO LIBRARY

UFOs over statues

UFOs over Easter Island statues. Computer artwork of spacecraft (unidentified flying objects, UFOs) hovering over moai statues. This could represent the belief that alien life forms visited Earth and imparted knowledge to ancient man. There are around 1000 statues that stand on Easter Island in the South Pacific, carved out of volcanic rock by islanders between 400 and 1500

© VICTOR HABBICK VISIONS/SCIENCE PHOTO LIBRARY

Gallstones, artwork

Gallstones. Cutaway computer artwork showing gallstones (brown, lower left) in a human gall bladder (red, oval). The gall bladder is a small muscular sac lying under the liver (not seen). It expels bile (a fat emulsifier) into the intestine through the bile duct (tube, lower right). Gallstones are hard deposits of salts or cholesterol that form in the gall bladder when the chemical composition of bile is upset. They are most common in women, the elderly and the obese. They usually cause no symptoms unless one becomes stuck in the bile duct, which can lead to acute pain, jaundice and infection. Surgical removal of the gall bladder is sometimes necessary

© GUNILLA ELAM/SCIENCE PHOTO LIBRARY