From Skies to Stars - March 2013
It Ain’t Over Yet
By Ed Downs
Yes, February was a real “high five” for both amateur and professional astronomers. Astronomy, often thought of as a “geek” profession (or hobby) by the multitudes who would rather watch late night television as opposed to freezing their tushies off while stooped over a telescope, may reconsider their opinions. Clearly, astronomy is a participative sport that involves loud noises, close calls, frightening damage and reflection upon the many science fiction movies dealing with annihilation by giant meteors, comets or asteroids. And it ain’t over yet!
February started out with excitement as the world waited for the fly-by of asteroid 2012DA14. With a diameter of approximately 160 feet (such objects are seldom spherical); 2012DA14 was expected to pass within 18,000 miles of earth, truly a “near miss,” being inside the orbit of a number of communication satellites. Then, just 16 hours before this asteroid was to buzz our planet, a 10,000 ton meteorite, 55 feet across, ripped into the Earth’s atmosphere over Russia, moving at 44,000 mph. To put that in perspective, moving at that speed one could fly from New York to LA in 4 minutes or cover the distance from the Moon to Earth in about 5.3 hours – our astronauts took 3.5 days to do the same. It exploded 12 to 15 miles above the surface of the earth, creating an air burst of 500 kilotons of TNT (30 times larger than the Hiroshima A-bomb). More than 1,000 people were injured from shattered glass and other debris over a 30-mile radius. This writer was just gearing up to watch the 2012DA14 fly-by when we received a firm reminder that “we are not alone in space.”
The Russian meteorite was in fact, a victim, as it wandered into earth orbit and was “run over” by our planet. Of particular interest was the response of some cable news stations, which tagged the meteorology department (after all, it does have the word “meteor” in it) for expertise. This news station confidently told viewers that NASA was quickly developing technology to see such meteors and will then be able to destroy them with lasers. To put it kindly, that is not true. NASA’s Near Earth Object (NEO) program is earth based and severely limited with respect to locating small objects that present a real danger to us earth-dwelling critters. Fortunately, the political and scientific communities of Canada (Canadian Space Agency) pretty sophisticated and had just launched (days before this was written) the Near-Earth Object Surveillance Satellite, or NEOSSat, that will seek out and track space rocks orbiting the sun from its position in Earth orbit. The satellite will also track space debris and satellites still in service in Earth’s orbit, splitting time between its two missions. Launched from India, this $25 million dollar project is super cheap by U.S. standards (a modest Lotto win) and offers observational capabilities not possessed by NASA.
Fortunately, a private group, known as the B612 Foundation, and led by well-known former astronauts and leading scientific experts, is taking up the challenge of protecting our planet. The B612 Foundation recently released details of a spacecraft called Sentinel, which could be launched as early as 2017. Its objective is to find and track a half million asteroids in Earth’s vicinity, accounting for up to 90 percent of those with diameters of at least 450 feet (140 m) over its five-and-a-half-year mission. While efforts now underway to locate NEO’s would not have caught the recent Russian meteor, the technology is evolving that can create an early warning system, if not an ability to “shoot down” such intruders.
But the excitement is not over. We now have a very active sun spot showing us some of the largest solar flares we have seen in recent times. Do not be surprised if we see interruptions to communication and GPS services. Also, get ready for Comet Pan-STARRS to give us a fly-by in mid-March. Experts are not yet sure of just how bright this comet will be, but certainly a pair of binoculars will make it clearly visible. It can be seen from March 7 to 20, low on the western horizon, about 30 minutes after sunset. At only 10 degrees above the horizon, the approximate width of your fist held at arm’s length, it will appear as a dim star moving in relation to fixed stars. To be sure, this amateur astronomer will brave the cold nights and join the adventure of watching our ever-changing solar system.
One last thought: Why so much activity now? Well, it all started for Earth about 4.6 billion years ago when early debris coalesced from galactic gasses and matter to compress into rocks and asteroids, which then collided to form early planetessimals (baby planets). As the mass of the baby earth increased its gravitational influence, millions of additional collisions occurred and the earth we know as our “space ship” evolved. The process of collision and growth has never stopped, and never will. Fasten your seat belt!
