The nearly simultaneous and completely coincidental occurrences of a near miss by an asteroid and the biggest meteor to hit the Earth in more than a century have prompted a lot of questions. There is so much that is fascinating about these objects, from their danger (one will eventually be on a collision course with the Earth) to their promise (some are potential sources of great wealth), that I can imagine a book-length Star Struck post! My time and most likely your patience preclude that for now, although I’d like to return to the topics in smaller segments in the near future. For now, I decided to send you to a few of the best web links I have found on a variety of topics related to Near Earth Objects.
Near Earth Objects are strictly defined as anything whose closest approach to the Sun is less than 1.3 astronomical units (AU), one AU being the average distance of the Earth from the Sun. NASA has a page full of information here and you can plot orbit diagrams for them if you like. This application lets you take a 3D look at the orbit, always helpful in really understanding why orbits don’t always really intersect when you think they do. Type in 2012 DA14 to see the orbit of the near-miss asteroid of February 15, 2013. This nice FAQ page tells how they are found and how the danger of an impact is assessed.
In what truly was a cosmic coincidence, the largest meteor to strike the Earth in more than a century streaked through the Russian skies a mere thirty hours before 2012 DA14’s closest approach. The inimitable Emily Lakdawalla rounds up some informative links, including this great illustration of why the two events are unrelated.
More than thirty years ago a team of scientists found evidence of a massive asteroid impact coinciding with the mass extinction that killed off the dinosaurs 65 million years ago. Lingering skepticism about this proposal has pretty much been laid to rest by recent results.
Russia has been the scene of the two biggest meteor strikes of the last 105 years. The Tunguska event of 1908 took place over largely uninhabited territory, which was a very good thing. Slate has collected some historical documents, some (but by no means all) of which require fluency in Russian.
NASA is so cash-strapped that most of the search for potentially hazardous objects is farmed out to private organizations. Preeminent among those is the B612 Foundation. Extra points to anyone who knows the origin of the name without clicking on this link!
Despite Armageddon and Bruce Willis and Ben Affleck, nuclear weapons are not the first choice for saving the Earth from an impending asteroid impact. Phil Plait discusses the general topic, and an MIT student’s clever method involves paintball!
Most asteroids are just rock, interesting to scientists but not of any immediate economic value. A few, however, are metallic, remnants of the cores of small planetesimals that shattered early in the solar system’s history. The value of a million tons of high purity metal should be obvious. Get on board with Planetary Resouces if you want to be an asteroid miner. Check out a paper on just how feasible and profitable this might be before you sign up.