A Mars Sampler
April 25, 1998 | Volume 153 | Number 17Cover: In 2007, a spacecraft orbiting Mars will blast off on its return trip to Earth, carrying samples of rock and soil stored on the surface of the Red Planet by a previous mission. The ring-shaped device is the first stage of the craft's propulsion system. (Illustration: Michael Carroll)
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News of the Week:
Dust Disks Hint at Nearby Planets
Radio and infrared images suggest that three nearby stars have recently spawned planets and might still be in the throes of forming a solar system.
X-ray flashes illuminate general relativity
Observations of rapid oscillations in the intensity of X rays emitted by a neutron star provide a novel test of Einstein's general theory of relativity.
Birds eggs started to thin long before DDT
A study of old museum eggs has revealed that shells started thinning in Britain at the time of the Industrial Revolution almost 50 years before the introduction of DDT.
Butterfly may use flowery stepping-stones
Contrary to conservation biology dogma, the rare Fenders blue butterfly may do better with patches of habitat than with a corridor linking potential sites.
Ulcer bacteriums drug resistance unmasked
Researchers have deciphered the method by which an ulcer-causing bacterium becomes resistant to the antibiotic used in Flagyl, MetroGel, and Protostat.
Cold viruses enter cells without knocking
The three-dimensional structure of a receptor protein reveals how it allows cold viruses to enter cells.
Stress hormone may speed up brain aging
High concentrations of a major stress hormone in the elderly may contribute to atrophy of a brain structure crucial to memory and spatial navigation.
My mother, the clone?
Dolly, the famous cloned sheep, reportedly is pregnant.
BiologyPunching up the activity of genes
A protein involved in the growth of embryonic brain cells may also play a role in blood vessel growth.
Brain and blood vessels share cues
Scientists have found a way to turn on random genes in fruit flies.
Manatees win some and lose some
The population of manatees in remote regions of Florida appears to be increasing, but populations on Floridas populous southern Atlantic coast may be decreasing.
Where have all the flowers gone?
The World Conservation Union has issued the first worldwide list of threatened plants.
BiomedicineSynthetic hormone spurs girls' growth
When given daily between the ages of 8 and 14, somatropin increases growth but not psychological outlook, in short girls.
Genetic flaw linked to breast cancer
A genetic variation that limits production of key detoxifying enzymes increases womens risk of developing breast cancer.
PhysicsLast of the normal mesons
Fermilab physicists have discovered a long-sought meson consisting of a charm quark and an antibottom quark.
A half-life for titanium
The most accurate set of measurements to date established the half-life of titanium-44 as 59.2 years.
Microdrops of superfluid
Superfluidity can occur in a cluster consisting of as few as 60 helium-4 atoms.
Articles:Scooping Up a Chunk of Mars
Fresh samples from the Red Planet
Relying on a trio of small missions, NASA expects by 2008 to have gathered, stored, and carried to Earth bits of rock and soil from Mars.
The Name Game
Young kids grasp new words with intriguing dexterity
The apparent ease with which 2-year-olds learn new words may reflect their budding social insights about adults' intentions.
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