Stellary Starry Universe

Research by NASA and international scientists concludes giant asteroids, similar or larger than the one believed to have killed the dinosaurs, hit Earth billions of years ago with more frequency than previously thought.

This artist’s illustration gives an impression of how common planets are around the stars in the Milky Way. The planets, their orbits and their host stars are all vastly magnified compared to their real separations. A six-year search that surveyed millions of stars using the microlensing technique concluded that planets around stars are the rule rather than the exception. The average number of planets per star is greater than one. This means that there is likely to be a minimum of 1,500 planets within just 50 light-years of Earth. The results are based on observations taken over six years by the PLANET (Probing Lensing Anomalies NETwork) collaboration, which was founded in 1995. The study concludes that there are far more Earth-sized planets than bloated Jupiter-sized worlds. This is based on calibrating a planetary mass function that shows the number of planets increases for lower mass worlds. A rough estimate from this survey would point to the existence of more than 10 billion terrestrial planets across our galaxy. The results were published in the Jan. 12, 2012, issue of the British science journal Nature. Image Credit: NASA, ESA, and M. Kornmesser (ESO)

A new NASA outreach project will enlist the help of amateur astronomers to discover near-Earth objects (NEOs) and study their characteristics.

Space shuttles Enterprise, left, and Discovery meet nose-to-nose at the beginning of a transfer ceremony at the Smithsonian’s Steven F. Udvar-Hazy Center, Thursday, April 19, 2012, in Chantilly, Va. Space shuttle Discovery–the first orbiter retired from NASA’s shuttle fleet, completed 39 missions, spent 365 days in space, orbited the Earth 5,830 times, and traveled 148,221,675 miles–will take the place of Enterprise at the center to commemorate past achievements in space and to educate and inspire future generations of explorers at the center. image Credit: NASA/Smithsonian Institution/Carolyn Russo

Space shuttle Discovery, mounted atop a NASA 747 Shuttle Carrier Aircraft, is seen as it flies near the U.S. Capitol, Tuesday, April 17, 2012, in Washington. Discovery, the first orbiter retired from NASA’s shuttle fleet, completed 39 missions, spent 365 days in space, orbited the Earth 5,830 times, and traveled 148,221,675 miles. NASA will transfer Discovery to the National Air and Space Museum to begin its new mission to commemorate past achievements in space and to educate and inspire future generations of explorers. Image Credit: NASA/Smithsonian Institution/Harold Dorwin