JUL 4, 2011 - Asteroid Alert is a mobile astronomy app for Apple iOS devices (iPhone, iPod Touch, iPad) that may have extra appeal since last week's near-miss Asteroid 2011 MD fly-by. Had that piece of space rock, which is about the size of a house and speeding along at nearly 7 km./sec. (a brisk 15,000 mph), come in just a little closer, it would have made a great, big, spectacular sky-show as it burned up in Earth's atmosphere - enough to put tonight's Independence Day fireworks to shame, I should think. As it was, the errant asteroid passed within about 19,000 km. (less than 12,000 miles) of our home planet - as close as 12,000 km (7,500 miles), according to most sources. Asteroid Alert won't let similar space rocks sneak up on you. If you download this free app to your iPhone, you can check up on what's careening toward you from out there in space. (The app downloads the data from NASA's Near Earth Object Close Approaches web page, in case you want to hit it up from your PC.) One word of caution, for what it's worth: I'm suspicious of the distance and velocity figures given by Asteroid Alert, since they don't agree with other published sources. I'll follow up on this, if I get anything definitive in the way of a response from the developer.
