Travis Goodspeed has authored a blog post detailing his method of tracking low-earth-orbit satellites. Starting with an old Felcom 82B dish made for use on maritime vessels, he added motors to move it around and a webcam-based homemade calibration system. "For handling the radio input and controlling the motors, I have a BeagleBone wired into a USB hub. These are all mounted on the trunk of the assembly inside of the radome, sending data back to a server indoors. ... In order to operate the dish, I wanted both a flashy GUI and concise scripting, but scripting was the higher priority. Toward that end, I constructed the software as a series of daemons that communicate through a PostgreSQL database on a server inside the house. For example, I can run SELECT * FROM sats WHERE el>0 to select the names and positions of all currently tracked satellites that are above the horizon. To begin tracking the International Space Station if it is in view, I run UPDATE target SET name='ISS';. For predicting satellite locations, I wrote a quick daemon using PyEphem that fetches satellite catalog data from CelesTrak. These positions are held in a database, with duplicates filtered out and positions constantly updated. PyEphem is sophisticated enough to predict in any number of formats, so it's easy to track many of the brighter stars as well as planets and deep-space probes, such as Voyagers 1 and 2."
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New submitter rogue_archivist writes "I'm an archivist at a mid-sized university archives, trying to develop a policy for archiving computer files ('born-digital records' in archival parlance). Currently old floppy disks, CDs, and the occasional hard drive are added to our network storage. Then the physical media is separated from archival paper documents and placed into storage. My question for all you slashdotters out there is: should these disks be imaged and then the physical copies discarded? Is there any benefit for keeping around physical copies of storage media long since rendered obsolete?"
hypnosec writes "Adapteva has started shipping its $99 Parallella parallel processing single-board supercomputer to initial Kickstarter backers. Parallella is powered by Adapteva's 16-core and 64-core Epiphany multicore processors that are meant for parallel computing unlike other commercial off-the-shelf (COTS) devices like Raspberry Pi that don't support parallel computing natively. The first model to be shipped has the following specifications: a Zynq-7020 dual-core ARM A9 CPU complemented with Epiphany Multicore Accelerator (16 or 64 cores), 1GB RAM, MicroSD Card, two USB 2.0 ports, optional four expansion connectors, Ethernet, and an HDMI port." They are also releasing documentation, examples, and an SDK (brief overview, it's Free Software too). And the device runs GNU/Linux for the non-parallel parts (Ubuntu is the suggested distribution).
Nerval's Lobster writes "Last week, Microsoft announced that it would take a $900 million write-off on its Surface RT tablets. Although launched with high hopes in the fall of 2012, the sleek devices—which run Windows RT, a version of Windows 8 designed for hardware powered by the mobile-friendly ARM architecture—have suffered from middling sales and fading buzz. But if Microsoft decides to continue with Surface, there's one surefire way to restart its (metaphorical) heart: make it the ultimate bargain. The company's already halfway there, having knocked $150 off the sticker price, but that's not enough. Imagine Microsoft pricing the Surface at a mere pittance, say $50 or $75 — even in this era of cheaper tablets, the devices would fly off the shelves so fast, the sales rate would make the iPad look like the Zune. There's a historical precedent for such a maneuver. In 2011, Hewlett-Packard decided to terminate its TouchPad tablet after a few weeks of poor sales. In a bid to clear its inventory, the company dropped the TouchPad's starting price to $99, which sent people rushing into stores in a way they hadn't when the device was priced at $499. Demand for the suddenly ultra-cheap tablet reached the point that HP needed weeks to fulfill backorders. (Despite that sales spike, HP decided to kill the TouchPad; the margins on $99 obviously didn't work out to everyone's satisfaction.) In the wake of Microsoft announcing that it would take that $900 million write-down on Surface RT, reports surfaced that the company could have as many as six million units sitting around, gathering dust. Whether that figure is accurate—it seems more based on back-of-napkin calculations than anything else—it's almost certainly the case that Microsoft has a lot of unsold Surface RTs in a bunch of warehouses all around the world. Why not clear them out by knocking a couple hundred dollars off the price? It's not as if they're going anywhere, anyway."