China has a plan to launch a new project an “Artificial Moon” that will light up the skies as far as 50 miles around. The artificial Moon will be eight times brighter and stronger than real Moon. It will be realized in 2010 in the southwestern city of Chengdu.
Rare asteroid 2017 YE5 (each about 3,000 feet (900 meters) in size, orbiting each other) was discovered by new observations by three of the world ‘s largest radio telescopes.
Near-Earth asteroid 2017 YE5 was discovered with observations provided by the Cadi Ayyad University Morocco Oukaimeden Sky Survey on December 21, 2017.
“On June 21, the asteroid 2017 YE5 made its closest approach to Earth for at least the next 170 years, coming to within 3.7 million miles (6 million kilometers) of Earth, or about 16 times the distance between Earth and the Moon”, indicates NASA.
Scientists at the Arecibo Observatory in Puerto Rico had already planned to observe 2017 YE5.
The new observations between June 21 and 26 point out that the two asteroids revolve around each other once every 20 to 24 hours. This was confirmed with visible-light observations of brightness variations by Brian Warner at the Center for Solar System Studies in Rancho Cucamonga, California.
“Radar imaging shows that the two objects are larger than their combined optical brightness originally suggested, indicating that the two rocks do not reflect as much sunlight as a typical rocky asteroid. 2017 YE5 is likely as dark as charcoal. The Goldstone images taken on June 21 also show a striking difference in the radar reflectivity of the two objects, a phenomenon not seen previously among more than 50 other binary asteroid systems studied by radar since 2000. (However, the majority of those binary asteroids consist of one large object and a much smaller satellite.) The reflectivity differences also appear in the Arecibo images and hint that the two objects may have different densities, compositions near their surfaces, or different surface roughnesses” says NASA.
Scientists have an opportunity to understand different types of binaries and to study the formation mechanisms between binaries and contact binaries which was provided by the discovery of the binary nature of 2017 YE5. The analysis may let researchers guess the densities of the 2017 YE5 objects.