Nasa Live Earth

What would happen if something the size of a mountain, flying at 26 000 miles per hour (41 843 km / h), press the earth? What our governments have a plan in place to protect us against such a calamity? Judging by the slow reaction of the administration before and after Hurricane Katrina the likely answer is "No".

We live in a lively atmosphere of the solar system, with many moving parts. Many of these pieces are made of stone materials of iron known as asteroids and many of these rocky bodies have not yet been discovered and could impact with Earth at any time.

There are also many icy bodies, known as Comets. They live from the orbit of Neptune. While stirring of their orbits, perhaps nudged by gravitational forces of nearby stars can change their trajectories for a visit to the inner solar system to put them on a potential collision course with Earth, so at any time.

Scientists study recent developments

In January 2008 there have been some news that an asteroid known as 2007 WD5, might hit the planet Mars. The resulting impact was projected to be similar in size to Meteor Crater, an impact crater a mile wide in Arizona, formed in a flash of white light and fireball, when a asteroid struck there 50 000 years.

Around the same time, another known asteroid in 2007 TU 24 was discovered in November 2007 by the Catalina Sky Survey on October 11, 2007. Calculations determined that pass close to Earth on January 29, 2008, just outside the orbit of the Moon, which is considered very close in astronomical terms.

2007 TU 24 is between 150 and 600 meters in diameter. The average interval between actual Earth impacts for an object of this size is estimated at about 37 000 years. Radar observations of 2007 GMT 24 were made at the Goldstone, California in late January and early February. This will allow later reconstruction of 3D shape.

In July 1994, twenty one of the fragments of comet Shoemaker-Levy 9 on Jupiter broken, leaving black and brown spots on the planet for over a year, each spot itself, the size of Earth. Astronomers have yet to witness an asteroid impact with another planet.

Therefore, the opportunity to see the impact on the planet in March 2007 WD5 was exciting for astronomers and scientists who wanted to make measurements of these types of objects as well as calculations and impact scenarios of what could happen if an asteroid or comet impact with Earth.

The impact on Mars has never held that the asteroid crossed without incident, a disappointment to astronomers who have lost the opportunity to observe the direct effects of an asteroid impact on a planet similar to Earth.

Fortunately for us, however, Earth asteroid 2007 TU 24 also failed. I could not help but wonder how we could actually be answered if scientists told us that the asteroid with the Earth-bound is headed directly for us and that, according to their calculations there was no way he would miss us!

How worried should we be?

One of the main problems we have now is the lack of an effective response. Even if we knew that an asteroid or comet was headed straight for us, and even if we had plenty of warning in advance, what would we do? Once we detect them we still find a way to safely and reliably destroy or divert them. To date, these methods are not in training, only in theory. No mission to prove the ability to move or destroy an asteroid or comet that have already been undertaken by a country.

If an asteroid hitting the Earth, the impact would probably be in the oceans of the Earth is more than 70% water. The effects of such impact.