DISCOVERIES FROM VENUS AND MARS

PLANETARY EXPLORATIONS have been striking pay dirt lately, revealing new information about Venus’ atmosphere and Mars’s geologic history. The discoveries—and more are promised—are leading to new insights into our planetary neighbors. Detection of the important and reactive hydroxyl radical in the atmosphere of Venus could lead to a better understanding of the planet’s climate. And discovery of almost pure silica on Mars suggests the planet might have once been wet and habitable. Also, at C&EN press time, scientists were anticipating that the $460 million Phoenix Mars Lander would touch down on the red planet on May 25 and begin probing the martian surface. Now that the hydroxyl radical, which helps clear pollutant molecules from Earth’s atmosphere, has been found in Venus’ atmosphere, scientists may begin to learn how this reactive species affects other molecules there, such as CO 2, ozone, and oxygen. Sensitive spectrometers aboard the European Space Agency’s Venus Express spacecraft, which is orbiting that ...