Friday, January 22, 2010

Hidden asteroids are stalking the Earth

Hidden asteroids are stalking the Earth  :

TINY asteroid that buzzed Earth last week highlighted our planet's vulnerability to objects whose peculiar orbits put them in a game of hide-and-seek with us.

An Earth-based telescope spotted the 10-metre space rock hurtling our way just three days before a near miss on 13 January, when it flew by at just one-third of the distance to the moon . The asteroid is never expected to hit Earth and would burn up before hitting the ground in any case. But its unusual orbit seems ingeniously designed to evade our surveys. It is likely that a handful of objects large enough to cause harm are hiding under similar circumstances.

Large asteroids are relatively easy to spot because they reflect the most sunlight. But smaller asteroids - which can still damage Earth if they span at least 30 to 50 metres - are usually too dim for telescopes to detect except during brief close approaches to Earth. For a typical near-Earth asteroid, these occurrences are a few years or decades apart.

However, last week's unexpected visitor, called 2010 AL30, kept far enough from Earth to be invisible for more than a century. The prolonged avoidance occurred because the period of its solar orbit was 366 days - very close to Earth's year (though the close pass shifted the space rock into a 390-day orbit). Like a slightly slower race car that is periodically lapped by its competitor on a circular track, it stays far from Earth for long stretches.

"2010 AL30 may become a sort of 'poster child' for hiding asteroids," says Alan Harris of the Space Science Institute in Boulder, Colorado.

Similar "synchronised" asteroids may be hiding with periods of very close to two, three, four years and so on, Harris says. Those with periods of about four years pose the greatest risk to Earth, because they would be in sync with both Earth and Jupiter, says Timothy Spahr of the Minor Planet Center in Cambridge, Massachusetts. Such asteroids would be particularly influenced by Jupiter's gravity, which could nudge them onto a collision course with Earth.

Asteroids with non-synchronous orbits can also hide. Those with orbits mostly interior to Earth's - called Aten asteroids - spend most of their time in the glare of the sun as seen from Earth, so telescopes have trouble spotting them.

Despite our best efforts, the majority of hidden asteroids are too small and dim to be detected until they are practically on top of us - regardless of their orbits. "The sad part is, the bulk of the population is invisible to us most of the time," Spahr says.

Tuesday, January 12, 2010

RC heli with streaming video & iPhone control

RC heli with streaming video & iPhone control:

The recently announced AR.Drone from Parrot may be the coolest toy I've ever seen. The AR.Drone quadricopter is controlled by iPhone & iPod Touch via wifi and provides a live video stream from the unit's 'cockpit'. It uses a second onboard cam facing downward to measure speed and compensate for turbulence, and in case of signal loss an autopilot control kicks in to handle landing. The unit is billed primarily as an augmented reality system for gaming, but looks like it'd be a ton of fun without any virtual goals. Parrot also offers an SDK for those interested in making applications for use with the AR.Drone. Look forward to seeing what devs come up with!

Friday, January 8, 2010

Google Nexus One Phone

Google Nexus One Phone

Google has unveiled their brand phone, the Google Nexus One($529 unlocked; $180 with a T-Mobile 2 years contract).
The Nexus one phone made by HTC, using Google's latest version of the Android operating system - Android OS 2.1, sports a 1GHz Qualcomm Snapdragon processor, features a 3.7 inch AMOLED touchscreen(480 x 800), a 5 megapixel camera with a built in LED flash, Wi-Fi connectivity, accelerometer, compass, GPS, stereo Bluetooth, and 3.5mm headphone jack. Other features include a trackball with a multicolor LED that displays different colors for different notifications

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