asteroid

Researchers find surprising characteristics of the asteroid

Since last July, NASA's Dawn spacecraft has been orbiting the asteroid Vesta and sending back images and other data to the delight and amazement of researchers. Among other surprising characteristics, Vesta has been shown to be one of the most colorful objects in the solar system.

Moment of impact: As the asteroid hits the ground with a velocity of several tens of kilometers per second, a shock wave is generated that penetrates radially into the ground and compresses the rocks.

Christian Koeberl, University of Vienna

Government research and development has its limits: Time, money and bureaucracy can all hamper the timely progress of research. As a result, many federal agencies are looking to private companies to help drive new innovation and keep costs down — but it’s never that simple. Two current hot-button topics — returning humans to space and geoengineering — highlight a range of issues related to how private and public investment in science can coexist. This month, we focus on NASA.

What the planet’s past mass extinctions tell us about the future of life on Earth

The crash-landing of a 10-kilometer-wide asteroid 65 million years ago made for a very bad day for dinosaurs — or one very lucky day for mammals.

About four years ago, a group of scientists proposed that a series of giant, wedge-shaped sandy deposits found along the shores of southern Madagascar might be evidence of a giant tsunami — a “mega-tsunami” — generated by an asteroid that may have blasted into the Indian Ocean sometime in the last 10,000 years. Furthermore, the scientists said, such impacts and the resulting tsunamis may have occurred fairly frequently during this period. To search for evidence of these impacts, the researchers formed the Holocene Impact Working Group.