~~Stars of the Brain~~ After years in the shadow of neurons, the star-shaped brain cells called astrocytes are moving into the research limelight. Once believed to be simply a supporting cast, the cells appear to play important roles in many brain scenarios. Shown is a human astrocyte in culture, almost 1 millimeter wide. (Photo by Steve Goldman)

Credit: Steve Goldman

Human astrocytes, like this one grown in culture, extend their branches and touch nerve synapses, modifying nerve function.
Credit: Steve Goldman

Astrocytes, like these in a slice from a rat brain, wrap the footlike ends of their branches around capillaries (arrow). The astrocytes collect nutrients from the bloodstream, which they pass on to neurons, and protect the brain from toxic agents.
Credit: Marie Simard

A neuron grown in culture without glia (above) shows many fewer synapses (bright dots) than a neuron cultured with glia does (below).
Credit: Ullian and Karen Christopherson

Hasse diagram for the divisors of 42.

Hasse diagram for a given poset and its corresponding geometric figure.

The shy green form of a desert locust nymph (right) can switch into a multicolored crowd lover if jostled.
Credit: Sword

Where the highest-energy cosmic rays graze the moon (light-gray area), microwaves may shoot Earthward.
Credit: Adapted from Peter W. Gorham/JPL

Ultraviolet light reveals kerogen-munching microbes (blue) surrounding fragments of organic material (orange) in this sample of New Albany shale.
Credit: Science

A fluorescent tag for a specific bacterial protein reveals a helical skeleton.
Credit: Carballido-López

Researchers reconstructed ancient climate patterns by using tree stumps such as this one in Southern Chile.
Credit: Roig