One of NASA's major research funds is aimed at the detection of large asteroids around the earth. Asteroids are one cause of the extinction of dinosaurs. Then will mankind also be extinct by asteroids? Or can humans avoid large asteroids? Let's look at the following reviews:
NASA categorizes asteroids that are about 45 million km away as NEOs (near-Earth Objects). An object of outer space measuring more than 100 meters has been categorized as a threat to humans because it can destroy or have a serious impact on the surface of the earth.
Since 1988 NASA has spent more than 100 million dollars on NEO detection and identification programs. But in 2014 they are more serious in its program due to the occurrence of the fall of Chelyabinsk meteors in Russia. NASA then get a budget of about 40 million dollars per year.
How Important Is It Detecting Asteroids?
As I mentioned in the previous article about the Great Disasters, asteroids are one of the disasters that have occurred in the past and caused the extinction of living things on earth, yes dinosaurs!
So the ability to detect the fall of this asteroid will give us a greater chance of survival.
Knowing the size and velocity of an asteroid gives us information about how severe the impact that can be caused by the impact with the earth. Knowing the coordinates of the fall and the timing of the collision allows us to determine the rare mitigation or evacuation to save the people on the site.
That is one way humans can avoid asteroids, but they are still not 100% safe because one of the worst impacts of asteroids is not only the impact but also the dust after the impact.
It turned out that in addition to preparing for information displacement position of the asteroid can also be used to shift the point of fall of the asteroid.
Meteor Chelyabinsk
One of the events of the latest meteor fall is on February 15, 2013, in the city of Chelyabinsk, Russia. The size of the meteor is small ie only about 20 meters but the fall speed reaches 60,000 km/hour.
This meteor fails to predict its arrival because the fall time coincides with the DA14 asteroid 2012 which also passes at its closest point to the earth. In addition to previous predictions, Meteor Chelyabinsk considered small enough size and will not harm the earth.
Meteor Chelyabinsk although destroyed at a height of 30km from the surface of the earth but can result in more than 1000 people injured.
The injured person is not because of the direct impact of the asteroid but because when the asteroid explodes with shiny light (brighter than the sun), the people in the office see the light in the sky without realizing that the shockwave (shock wave) from this collision is propagating towards the building.
The shock wave reaches the building and breaks the office glass which then injures the people who witnessed this meteor. So more than 1000 people suffered injuries from glass slices.
Are Humans Able to Avoid Asteroids?
Previously there may be people who think that humans already have nuclear weapons, why not destroy it with nuclear? Yeah, at first I also think like that, but it turns out to get the asteroid location very precisely when it has been headed to Earth is very difficult because there are so many influential styles there.
Not just the force of gravity but also the initial speed of the asteroids, the asteroid's asteroid angle, atmospheric density, even the process of destruction of asteroids by the Earth's atmosphere also gives a significant change of position so that firing a nuclear to the asteroid that falls to earth is very difficult to do.
It's like touching two ends of a sword at a very high speed.
The second way NASA has learned is to anticipate that the asteroid does not enter into the gravitational force of the earth, so before the asteroid reaches the Earth's gravity area it is hit by this asteroid with a spacecraft so that the asteroid trajectory changes.
But this way is also not very safe because of the uneven surface of the asteroid so that crash errors can actually make the asteroid into the earth's gravitational field and hit the earth faster.
One possible method is to take the asteroid using a specially designed spacecraft weighing several tons. When the spacecraft is juxtaposed with an asteroid in outer space, the pull force between the two will bind the asteroid and be able to move it to a new path (closer to the spacecraft).
Then if the shifting trajectory is considered still vulnerable to collision, then with a little rocket power we will shift the spacecraft slowly. The gravitational field between the spacecraft-asteroid will force the asteroid to shift also to a new, safer path.
This method was developed by a group of researchers called The B612 Foundation. Where they have tested this technique on small asteroids. The only requirement for this method to succeed is the long/long time.
Because the shift to be carried out is slowly until a proper new trajectory is found, this process takes quite a long time.
So if we managed to map the asteroid position and keep track of its path for the next few decades (predictable trajectory of large asteroids-asteroids can be done up to 20 years) then using the method of The B612 Foundation, humans can avoid asteroids.
For now, NASA can only map about 10% of all the asteroids in the NEOs so that humanity still needs a lot of effort in finding and mapping the existence of the objects of outer space around the earth.
Best Regard @h4f
Reference :
http://heavy.com/news/2016/02/chelyabinsk-russia-meteor-2013-size-damage-weight-injured-how-big-deaths-asteroid-meteor-hitting-earth-tx68-tx86/
http://www.businessinsider.com/heres-why-astronomers-did-not-detect-the-russia-meteor-ahead-of-time-2013-2
https://oig.nasa.gov/audits/reports/FY14/IG-14-030.pdf
http://www.businessinsider.com/nasa-was-given-36-million-extra-to-find-90-of-dangerous-asteroids-and-they-failed-2014-9
https://www.ted.com/talks/phil_plait_how_to_defend_earth_from_asteroids