Collisions between space objects are a vital part of the evolution of our Solar System. Most of Earth's impact craters have been wiped away due to plate tectonics, but evidence of such cosmic catastrophes, such as Arizona's 50,000-year-old meteor crater, do remain. When is Earth due for another major blast? Meet the professional and amateur astronomers who may be the first to know: first at LINEAR, a near-earth asteroid detection facility in New Mexico, and then at the Smithsonian's Minor Planet Center, where orbits of near-earth objects are tracked for possible hits and misses.
Science Bulletins is a production of the National Center for Science
Literacy, Education, and Technology (NCSLET), part of the Department of
Education at the American Museum of Natural History. This visualization
was supported by the National Oceanic and Atmospheric Administration
Taking a census of all the luminous objects in one-quarter of the visible cosmos is a hefty accounting job. It takes a specially-built telescope on task every clear night for eight years, wielding one of the biggest digital cameras on the planet. Over a hundred million stars, galaxies, and quasars have been tallied so far. Meet the astronomical observers and theorists set on divining the three-dimensional structure and origins of the Universe from these unprecedented scores of data.
Search a database with more than 8,300 reptile species. Learn about amphibian biology and conservation. Review the evolutionary history of squamates. And find hands-on science activities.
Three of the most catastrophic volcanic eruptions in geologic history occurred at a place now visited by nearly four million people a year: Yellowstone National Park. The magma chamber responsible still lies beneath, and continues to steam, heat, and shift the park landscape. Science Bulletins talks with the geologists regularly monitoring these disquieting signals to understand where this active region lies in its volcanic life span.
Explore the McLaughlin gold mine in Northern California. See the first metal coins, which were created in the Middle East around 600 BC. And investigate the properties of gold.
Bolivia’s diversity of animal and plant life is among the greatest in the world. Learn why the country has designated more than 17 percent of its land as protected areas.
How much can you reduce your carbon dioxide emissions? Is it worth it? Learn how simple choices multiplied by everyone in your community can make a big difference.
The MESSENGER orbiter's January 2008 flyby of the planet Mercury was historic. The last time a spacecraft visited was 1975, and it only mapped half the planet. MESSENGER is now sending back a complete picture of Mercury, shedding light on its geological history. But the ongoing mission will return much more than images. Its data on the planet's core, magnetic field, composition, and other attributes will help scientists answer pressing questions about the evolution of the terrestrial planets and even the Solar System itself. In the feature video, watch the MESSENGER science team react as the orbiter's first images of Mercury roll in. To explore the images in detail, click on the slide show at left. Find out more on the mission by clicking on the essay "First Planet Finishes Last."