Asteroid 2007 VK184 crossed out as potential menace for the planet
Since asteroid 2007 VK184 was discovered in November 2007 by the NASA-funded Catalina Sky Survey (CSS) at the University of Arizona has been added in the NASA´s asteroid impact hazard list. It was considered a real threat for a number of years with an estimated size of 130 meters and a rating of 1 on the 10-point Torino Impact Hazard Scale. Now 2007 VK184 has been permanently removed from the NASA´s list. (Image: NASA/JPL) Just
Space Weathering on Asteroids as Reason for their Disintegration
All surfaces of rocky bodies in our planetary system are exposed to a certain bombardment of (tiny) bits of rocks, so-called meteorites. Most ejecta out of these impacts are falling back to the lunar surface to build a layer of dust with time called regolith. Since that we have seen the nice footprints of astronauts in the lunar dust as proof: The Moon`s gravity is strong enough to capture a good part of the ejecta.
Metallic asteroids: threat or benefit?
«Our results suggest a higher number of metallic objects in the Solar System than previously suspected» said Alan Harris from the DLR Institute of Planetary Research in Berlin. Thanks to the new infrared method will be possible to identify many other metal-rich asteroids. What surprised the scientists was that metallic asteroids emit less thermal radiation than rocky asteroids when analyzed by an infrared telescope. Alan Harris and Line Drube using the principle of thermal conductivity
NEOShield’s target object comes close to Earth
Figure 1: Plot of the orbits of all presently known Potentially Hazardous Asteroids (PHAs), i.e. over 1400 as of early 2013. PHAs are asteroids with a size of at least 140 m and with orbits passing the Earth orbit within 7.5 million kilometres. The Earth orbit is shown by a bold black nearly circular ellipse. (Image: NASA/JPL – Caltech) Several possibilities exist to deflect a NEO such as to mitigate its impact risk. The focus