The Asteroids Are Coming! Friday, Planet Earth Meets “1998 QE2″
The Brenner Brief - “1998 QE2″ is not referencing quantitative easing; rather, an asteroid on its way to earth. Planet earth will meet 1998 QE2 on Friday, May 31, but they won’t quite shake hands.
On Friday, May 31,2013 at 1:59 p.m. PDT, a large asteroid designated
as 1998 QE2, will come as close to earth as its orbit dictates once
every 200 years. However, “close” is a relative term that easily gets
lost when describing things and events that occur in our cosmos. Close,
in this case, is 3.6 million miles (about 15 times the distance between
earth and the moon). Another measure that is rightly attributed to such
objects is their size, in this case 1.7 miles long, which is quite large
for such objects that are referred to as Near Earth Objects (NEO).
are large chunks of spatial debris that never grew large enough to
become a planet in their own right, but attach themselves to the
gravitational pull of established planets or a sun. There are also some
asteroids that seemingly float through space looking for a gravitational
orbit or a large heavenly body to implode upon, such as earth. They
travel at varying speeds in the tens of thousands of mph relative to the
The 1998 QE2 asteroid was discovered 15 years ago and has more than
one possible origin. It is in an earth orbit and considered of very low
risk to us for the foreseeable future, which in astronomical time is
more than your genealogy tree can even imagine. It will be back again in
2119, presumable in the same orbital path.
are declared safe from any harm from this identified asteroid, but what
about other asteroids? There are substantial efforts at identifying the
larger asteroids in orbit around earth, of which there are 980
identified at 0.6 miles in diameter or greater. But, as the asteroids
get smaller, identifying them, which includes predicting their orbits,
has a far less satisfying status. Only 30% of the 4,700 asteroids of
about 330 feet in diameter,that come uncomfortably close at some point
in their orbit, have been identified. Such space rocks could destroy an
area the size of a state if they collided with us. As the categories of
asteroids that travel in earth’s orbit get smaller, they are
increasingly more difficult to identify or predict.
A case in point is earlier this year on February 15, there was an
identified flyby of asteroid 2012DA 14, a 130 foot wide space traveler
that came within 17,200 miles, that was of no particular threat to
earth, but was within the distance of geosynchronous orbits (an orbit
height that will keep a satellite in exactly the same location over a
place on earth). Surprisingly on that same day an unidentified asteroid
collided with our atmosphere and exploded over Chelyabinsk, Russia,
causing considerable damage to property with claims of up to 1500
injuries, but no directly attributable deaths. We had no idea at all
that it was coming and it was only coincidental that it occurred on the
same day as 2012DA 14.
does not seem to get adequate notice is the number and size of
meteorite hits on the earth’s surface. A meteorite is a meteor that has
hit the earth’s surface and a meteor is an asteroid that has entered the
earth’s atmosphere. On those clear nights that you can see the shooting
stars in abundance, keep in mind that those are some of our smaller
space objects burning up in our atmosphere.
Almost all meteorites that have been studied are made up of iron,
nickel or cobalt or mixes of these heavy metals. Those are mighty heavy
stones hurtling through space. There are some very forward thinking
programs aimed at mining such valuable resources from nearby large
asteroids, but that is a really long time off. We have all seen pictures
of craters from meteor hits in our own earth’s history. Pictures of a
few of the larger ones are attached, but the this site will show you a list of the ten largest, including Chicxulub Crater in the Yucatan Peninsula of Mexico credited with leading to the extinction of dinosaurs.
Just looking at the moon through even a modest set of binoculars or
telescope will show the many craters on the moon’s surface. Because the
moon has no atmosphere to burn up asteroids, they will all make it to
the surface, but there are some mighty big craters visible.
One of the most recent damaging asteroid collisions with earth is referred to as the 1908 Tunguska Event. That year a 130 foot wide object exploded over Siberia’s Podkamennaya Tunguska River,
flattening roughly 825 square miles of forest. It is somewhat
disconcerting to realize that less than 1 percent of asteroids of this
size or bigger have been identified. That means that we have an
undetermined amount of good-sized projectiles orbiting our earth, and
some with diminishing orbits. But, then again, the frequency of one of
these rocks falling to earth is very low, maybe even every 40,000 years,
but where are we in that cycle?
Editor’s Note: On Friday, May 31 at 2pm ET, the White House will have a Google+ Hangout event with Bill Nye “The Science Guy” and others to discuss asteroids. Click here for more information.
Thanks to: http://aworldchaos.wordpress.com