SPACE WATCH (download wallpaper)
NASA – This celestial object looks like a delicate butterfly. But it is far from serene.
What resemble dainty butterfly wings are actually roiling cauldrons of gas heated to more than 36,000 degrees Fahrenheit. The gas is tearing across space at more than 600,000 miles an hour—fast enough to travel from Earth to the Moon in 24 minutes!
A dying star that was once about five times the mass of the Sun is at the center of this fury. It has ejected its envelope of gases and is now unleashing a stream of ultraviolet radiation that is making the cast-off material glow. This object is an example of a planetary nebula, so-named because many of them have a round appearance resembling that of a planet when viewed through a small telescope. more> http://tinyurl.com/ydyx397
By Joe Wlad, – When computing platforms are used in applications where safety or security is paramount, such as airborne and ground-based systems, special requirements may need to be addressed.
Modern microprocessors and operating systems provide memory protection that helps developers identify and contain application faults. In avionics systems, operating systems also provide time partitioning so that multiple applications can execute on a single CPU. Standards such as ARINC 653 have been published that define services an operating system shall provide when used in an environment with multiple applications. Additionally, developers use RTCA DO-178B and, in Europe, EUROCAE ED-12B as guidance documents to ensure their software complies with safety requirements. For applications with security requirements, the ISO 15408 standard is used for certification. more> http://tinyurl.com/4galbqw