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Comment Re:fall to Earth (Score 4, Informative) 122

and http://www.spacesafetymagazine.com/2013/09/14/european-satellite-goce-uncontrolled-reentry/ his will be the first uncontrolled reentry of an ESA satellite since Isee-2, in 1987. Unfortunately, it will not be the last, considering that the bus-size Envisat’s altitude is gradually decaying in Low-Earth Orbit without control. According to ESA, up to 25% of GOCE’s mass will survive the extreme reentry conditions to fall to the ground. However, the risk for populated areas is very small since the majority of the Earth is covered by oceans. “The major part of what survives to the surface will be the core instrument,” says Dr. Floberghagen. “From the original mass which we have now in space, we have estimated that about 25%, about 250 kilos, will reach the surface, and these 250 kilos will be distributed over between 40 and 50 fragments.” The fragments that survive will hit the ground in a 900 km long footprint. The reentry will be a good test for debris monitoring systems and fragmentation models.

Comment Re:fall to Earth (Score 5, Informative) 122

Some, but not all of it. http://www.spaceflight101.com/goce-re-entry.html : With its fins and aerodynamic shape, GOCE will maintain a stable position in orbit as it approaches entry. During entry, the spacecraft will likely remain in that position for the initial phase of re-entry until it breaks up. Following the destruction of the spacecraft, most of its components will harmlessly burn up in the atmosphere. However, it is known that about 20 to 40% of a re-entering satellite's total mass reach Earth's surface. Dense components of satellites usually impact 800 to 1,300 Kilometers downrange from the Orbital Decay Point. Their journey back to Earth is strongly influenced by atmospheric properties like crosswinds that play a major role during atmospheric descent.

Comment Re:Good idea (Score 1) 147

it depends what you call passed. 50%, 65%, 80% (here, that's the min undergrad, honours, grad grade to "pass"). Passing means you know enough to do that material, not that you understand it well enough to apply it without effort while learning the next level, so if you stopped there you could be considered to know the material.
Facebook

Wolfram Alpha Drills Deep Into Facebook Data 70

Nerval's Lobster writes "Back in January, when Wolfram Alpha launched an updated version of its Personal Analytics for Facebook module, the self-billed 'computational knowledge engine' asked users to contribute their detailed Facebook data for research purposes. The researchers at Wolfram Alpha, having crunched all that information, are now offering some data on how users interact with Facebook. For starters, the median number of 'friends' is 342, with the average number of friends peaking for those in their late teens before declining at a steady rate. Younger people also have a tendency to largely add Facebook friends around their own age — for example, someone who's 20 might have lots of friends in the twenty-something range, and comparatively few in other decades of life—while middle-aged people tend to have friends across the age spectrum. Beyond that, the Wolfram Alpha blog offers up some interesting information about friend counts (and 'friend of friend' counts), how friends' networks tend to 'cluster' around life events such as school and sports teams, and even how peoples' postings tend to evolve as they get older — as people age, for example, they tend to talk less about video games and more about politics. 'It feels like we're starting to be able to train a serious "computational telescope" on the "social universe,"' the blog concluded. 'And it's letting us discover all sorts of phenomena.'"
Internet Explorer

Microsoft Releases Internet Explorer 10 For Windows 7 321

An anonymous reader writes "Internet Explorer 10 for Windows 7 is out. Windows 8 may suck but now you can at least enjoy (most of) that version's Internet Explorer. IE10 for Win7, originally not planned, has seen the light of day after all — four months after it debuted in Windows 8. It is available via Windows Update as an optional update; however, if you've already installed a pre-release version, it will be updated automatically as an 'important' update. IE10 on Win7 requires a platform update to bring some Windows 8 APIs to the more mature Windows, and it will not feature embedded Adobe Flash as the Windows 8 version does (use the plug-in version from Adobe, as usual, instead)."

Comment Re:$4.30 MSP430 Launchpad for starters (Score 2) 228

I started with arduino, and I had no microcontroller experience. The community, examples from the absolute ground up, and vendor (sparkfun, adafruit, etc) support is excellent. It all makes for a really enjoyable experience. Digikey and mouser get you parts fast. Ebay and random asian websites get you parts slow but cheap. If you want graphics (eg. TV, or monitor) though, best go with the pi. A pi costs less than an arduino graphics shield. Ethernet is doable at least.

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