Thursday 7 February 2013

COSMIC WATCH

“Astronomy compels the soul to look upwards and leads us from this world to another.” - Plato
 

Next week, an asteroid will approach Earth in what is being described as a historic “close shave”. Astronomers say that there’s no chance that the rock will crash into our planet on this occasion. The 45 meter long asteroid 2012 DA14 will approach earth and on February 15 will be as close as 27,700 kilometres. This is extremely close and personal on cosmic terms, coming nearer than the ring of satellites that are in geosynchronous orbit. This will be the closest distance of approach that we know of in advance for such a large asteroid, however, there is no need to predict doom.
 

NASA has a special department called the “Near-Earth Object Program Office” and this can accurately predict the asteroid’s path with the observations and measurements already obtained. It is known that there is no chance that the asteroid might be on a collision course with Earth. The approach, however, will provide a unique opportunity for researchers to study a near-Earth object up close.
 

Asteroid 2012 DA 14 was discovered in February last year by astronomers with the La Sagra Sky Survey in Spain. The asteroid has been orbiting the sun once every 368 days, though next week’s close pass will reduce its orbital period to 317 days. At its closest approach on February 15, the rock will be just 1/13th as far from Earth as the moon is and will whiz by our planet at about 28,000 km/h as it makes its closest pass for at least the next 30 years.
 

The asteroid will be visible as a point of light through binoculars and small telescopes during the close encounter. The best observing will be from Eastern Europe, Asia and Australia, NASA officials said. 2012 DA 14 will have faded considerably by the time Earth’s rotation brings the object into view for people in the continental United States. Radar astronomers plan to take images of the asteroid about eight hours after closest approach using the Goldstone antenna in California’s Mojave Desert, which is part of NASA’s Deep Space Network.
 

Several other known asteroids have approached Earth even more closely than 2012 DA14 will, but those objects were all smaller. Asteroids of the size of 2012 DA14 flit past earth about once every 40 years and actually hit Earth every 1,200 years or so. Other relatively large asteroids have probably zipped very close to Earth recently without being spotted. Astronomers have identified more than 9,000 near-Earth asteroids to date, but perhaps a million or more such space rocks are thought to exist. If 2012 DA14 did strike our planet, it would likely cause serious damage on a local scale. An object of similar size flattened 2,000 square km of forest when it exploded above Siberia's Podkamennaya Tunguska River in 1908.
 

The asteroid seems to have a very prosaic name, but it reflects the rule of nomenclature for minor heavenly bodies. I think I’ll call it “Valentino” given its discovery by Spanish scientists around about February 14! There is already an asteroid called “Eros”!
 

As if this cosmic even wasn’t enough, a comet is approaching our sun and some scientists say it could dazzle as a “comet of the century” later this year. Comet ISON was discovered in September 2012 by Russian astronomers Vitali Nevski and Artyom Novichonok using a 0.4-metre telescope of the International Scientific Optical Network (ISON), near Kislovodsk. Incidentally, “ison” in Greek means a drone note, or a slow-moving lower vocal part, used in Byzantine chant and some related musical traditions to accompany the melody, thus enriching the singing, at the same time not transforming it into a harmonized or polyphonic piece. Hence the comet will enrich the music of the spheres!
 

Comet ISON will make its closest approach to the sun on November 28, when it will approach within 1.2 million km of our star’s surface. As of mid-January, the comet’s tail was more than 64,400 km. If the comet survives the approach, and does not fade or break apart, it could transform into a spectacular celestial sight, rivaling the full moon, scientists have said. The comet will make its closest approach to Earth on Dec. 26, when it will fly within 64 million km of our planet. It poses no impact threat to the Earth, NASA scientists said.

1 comment:

  1. See this article:

    http://theconversation.edu.au/look-out-close-encounters-of-the-asteroidal-kind-12009

    ReplyDelete