Romancing the Asteroid
Everyday approximately 100 tons of asteroid and comet material blanket the Earth, but like so many ships in the night, the asteroids and comets pass us by without ever meeting. Every so often though, once every 1,200 years or so, asteroids the size of 2012 DA14 meet the Earth, which is always a life changing experience.
Like the asteroid collision in the Yucatan approximately 66,038,000 (give or take 11,000 years) that is believed to be the final blow to the Cretaceous period of life on this planet (i.e. dinosaurs), only 8,900 near Earth asteroids have been discovered to date, including asteroid 2005 YU55, the asteroid roughly as wide as a city block that gave us a close call in 2011. Alas, as asteroid 2012 DA14 passes just 17, 100 miles away from Earth on Feb. 15th, it appears that the Earth and the star-like body shall be orb-crossed yet again.
This also means that the asteroid known as Apophis, discovered in 2004, is unlikely to plant one on Earth in about 30 years from now as was previously predicted. While Apophis has a diameter of about 325 meters, Asteroid 2012 DA14 is only 40 meters in diameter, but Asteroid 2012 DA14 will pass nearly 2,000 miles closer to Earth than Apophis will, according to the calculations of NASA scientists. Instead Apophis will pass the Earth at a distance of no closer than 19,400 miles, making the odds that Earth will draw Apophis in with its magnetism on April 13, 2029 less than one in a million. C’est la vie.
Asteroid 2012 DA14 will get very intimate with Earth, close enough to make moon babies. It will move well within the paths of satellites, which means there is a remote chance that 2012 DA14 could thoughtlessly knock one of those communication or navigation satellites sailing toward us, according to researchers at the Jet Propulsion Lab’s Near-Earth Object Program Office. This is one among many reasons why NASA scientists will watch 2012 DA14 closely from the Goldstone radar in the scenic Mojave Desert. This is an historic event. 2012 DA14 will get closer to Earth than any asteroid in recorded history, and while doomsayers might see that as an omen, astronomers view it as a great stroke of fortune.
What these close calls mean to scientists is an opportunity to study asteroids up close and personal, so that, like devising a plan to avoid a former lover, scientists can deflect them in the future when the two are inevitably and enigmatically drawn to each other. The scientists who will be monitoring the movements of 2012 DA14 will build a 3-dimenensional map of it, refine estimates on its shape, spin and reflectivity, and try to ascertain whether it’s made up of more iron than rock.
As Bill Nye explained on CNN, they won’t all be close calls, and the world we live in today is far different from the world the last time an asteroid the size of 2012 DA14 made contact. Unless an asteroid conveniently falls somewhere in the Western Sahara today, it will likely wreak terrible havoc. A potentially dangerous asteroid is one that is at least 500 feet wide and passes within 4.65 million miles of Earth.
In September of 2016, NASA plans to launch a space shuttle onto an asteroid. Origins-Spectral Interpretation-Resource Identification-Security-Regolith Explorer (OSIRIS-REx) will be the first U.S. mission to carry samples from an asteroid back to Earth, according to NASA. OSIRIS-REx will travel for three years to reach asteroid 1999 RQ36. It will then map the surface of the asteroid over the course of six months and, using a robotic arm, collect more than two ounces of material from the asteroid for return to Earth in 2023. NASA scientists estimate that the asteroid is approximately 1,900 feet in diameter or roughly the size of six football fields.
In the past, scientists have discovered organic molecules in meteorite and comet samples that indicated that some of life’s ingredients can be created in space. Asteroids are largely made of carbon, water, and platinum metals, which are the essence of both life and stars. Researchers believe that answers to important questions about the creation of our solar system and the beginnings of life on our planet can be uncovered by spending some time with asteroids.
To view 2012 DA14, it will be necessary to have a telescope, a good star map, and accurate positions of where the asteroid will be every minute. NASA’s Horizon System can provide some of the necessary ingredients. Unfortunately for those stargazers in North America who might be planning a romantic interlude under the nighttime sky this weekend, the 2012 DA14 show will be over before sundown. For complete coverage, see www.space.com.