... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... Risks Comparable to NEOs . ... The Increasing Rate of Discovery of Asteroids . ... Comet and Asteroid Collision Probabilities . ... Extreme albedo comets and the impact hazard (PDF Format) . ... Asteroid Impact Animations . ... Workshop on Scientific Requirements for Mitigation of Hazardous Comets and Asteroids - 2002 . ... The Spaceguard Survey Report, 1992 (PDF) . Tsunami from Asteroid/Comet Impacts . ...

Astronomy Picture of the Day . Evolution of the Moon . ... The Moon was likely created from debris expelled when a Mars-sized object violently impacted the Earth about 4.5 billion years ago. ... Rocks large and small continued to impact the surface, including a particularly large impact that created Aitken Basin about 4.3 billion years ago. A Heavy Bombardment period then continued for hundreds of millions of years, creating large basins all over the lunar surface. ... Apogee Full Moon . ...

... 2012 March 20 . Evolution of the Moon . Video Credit: LRO , SVC , NASA . ... The Moon was likely created from debris expelled when a Mars-sized object violently impacted the Earth about 4.5 billion years ago. ... Rocks large and small continued to impact the surface, including a particularly large impact that created Aitken Basin about 4.3 billion years ago. ... Over the next few billion years lava flowed into Earth-side basins , eventually cooling into the dark maria we see today. ...

Projectile Motion: In Aristotle's view, objects moved parallel to the Earth's surface until it was time (i.e. it was their destiny) to fall back to the earth . Aristotle believed that the "natural" state of massive objects was to seek the center of the Earth. When a stone is launched, an impetus is given to it to disturb it from its natural condition. ... Archimedes' catapults lobbed quarter-ton stones at the attacking Roman ships, quickly destroying the clumsy Roman siege engine. ...

... This paper describes the main algorithms used by the Einstein Level One processing to create the exposure masks and the background maps for Einstein IPC images, and how these algorithms were recreated in the IRAF environment. Our goal was to recreate the algorithms used by the Level One Processing to create exposure masks and background maps for Einstein Image Proportional Counter (IPC) data (cf. sections 2.5 and 2.7 of Harnden et al. ...

... The craters were caused by the impacts of comets and asteroids. ... In fact, up to a diameter of about 10 meters (33 feet), most stony meteoroids are destroyed in the atmosphere in a terminal explosion. ... The famous meteor crater in northern Arizona, some 1.2 kilometers (4,000 feet) in diameter and 183 meters (600 feet) deep, was created 50,000 years ago by a nickel-iron meteorite perhaps 60 meters (197 feet) in diameter. ... These range in diameter from a few meters to about 8 km. ...

... Pre-university education . ... Samara region . SSAU History . SSAU roadmap . ... Scientists of Samara State Aerospace University (SSAU) develop a unique 3D-printer for chocolate confectionery printing. 3D-printer for chocolate printing is being created in SSAU Centre for Robotic Complexes and Mechatronic Systems. ... Know-how of the scientists of Samara State Aerospace University in that they were developed unparalleled chocolate delivery and cooling systems in 3D-printer. ...

... Does the time it takes different methods to create all the elements coincide with the universeт??s accepted age? ... Illinois Urbana-Champaign) Different kinds of stars create elements at different rates, all of which are consistent with the age of the universe. Get instant access to subscriber content on Astronomy.com! ... Registration is FREE and takes only a few seconds to complete. If you are already registered on Astronomy.com, please log in below. ...