![]() Today, if we are hit by a major asteroid, that is not bad luck anymore. NARRATOR: For every near-Earth asteroid we have detected, there are thousands that we haven't.Įd Lu believes we need to locate and track them.ĮD LU: 50 years ago, 100 years ago, if we were wiped out by an asteroid, that was just bad luck. To put that in perspective, only about 20 years ago, we had less than 100. There are millions of these in orbits that pass near Earth.ĭON YEOMANS: We've discovered roughly 10,000 near-Earth objects that can get fairly close to the Earth. The immediate danger comes from smaller asteroids, less than one kilometer, or about 3,000 feet, across. The chances of a strike are vanishingly small. These are potentially large enough to cause a global catastrophe. Observations have revealed almost 1,000 asteroids larger than a kilometer in near-Earth orbits. NARRATOR: So how can we overcome the asteroid threat? We can maybe try and model where earthquakes happen, we can try to predict how frequently tornadoes happen.Īsteroid impacts, we might actually be able to do something about that in the very near future. Many now believe asteroids are a problem we can solve.ĬATHY PLESKO: Asteroid impacts are actually the first natural disaster that humans have a hope of really preventing. NARRATOR: Our asteroid knowledge and detection technologies have improved rapidly in recent decades. The entire city of Las Vegas was built upon the concept that the house always wins. With the experience of three missions and over 200 days in space, former Astronaut Ed Lu believes it's only a matter of time before one strikes us again. If they enter our atmosphere, they become potentially deadly meteors.Īny fragments that reach the ground, we call meteorites. Many of these near-Earth asteroids cross our path time and again. It's now en route to an even larger body: Ceres.īut not all asteroids stay in the asteroid belt.Ī random collision, a planet's gravity, even heat from the sun can knock them into a different orbit closer to Earth. NARRATOR: Today, we have the technology to visit these remote objects.Ģ011: NASA's Dawn probe approaches the Vesta, the second-largest asteroid in the solar system. They stay where they're supposed to be and they live their lives and evolve through their part of the solar system without ever coming close to the Earth. Out here, asteroids pose no threat to Earth.ĬATHY PLESKO: There are millions of asteroids and comets in the solar system.įortunately for us, most of them are on very stable orbits. The asteroid belt ranges from roughly 150 to nearly 500 million kilometers away. Our challenge is to understand these potentially devastating objects.Īsteroids are rocks left over from the birth of the solar system 4.6 billion years ago.Īs Mars and Jupiter form, they leave a ring of debris between them: the asteroid belt.Īsteroids are rocks that should form another planet, but Jupiter's gravity prevents them from coalescing. They can catch us completely by surprise. Our planet also bears the scars from much smaller strikes.īut the danger from asteroids still hangs over us today. ![]() It helps wipe out the dinosaurs and around 70% of species on the planet. It hits with the energy of over 100 atom bombs.Įverything from downtown to the outer city limits and beyond is completely obliterated.Ī rock approximately ten kilometers wide smashes into planet Earth. Perhaps then we could have saved ourselves. Ground based telescopes spot it just days before impact. It's 30 meters, or 90 feet, across, half the size of a small office building. It has orbited the sun for four-and-a-half billion years. NARRATOR: A rock tumbles through space: material left over from when the planets first formed. NARRATOR: Asteroids could be the biggest threat humanity faces. ![]() Perhaps we can learn to mine them for their wealth.ĬHRIS LEWICKI: There are millions and millions of these objects in the solar system, and we've only just begun to understand their resource potential. NARRATOR: But where some see danger, others sense an opportunity.Īsteroids contains precious metals and water. Only now do we have the ability to identify the threat and even the technology to neutralize it. We really need to upgrade the search capability. NARRATOR: Now the race is on to understand the danger. In 2013, a much smaller asteroid terrorizes this Siberian city.įor many, this really was a wake-up event. NARRATOR: 65 million years ago, a huge asteroid wipes out much of life on Earth. Some are on a collision course with earth.Īn asteroid has more damage potential than a nuclear bomb of the same energy. Trillions of tons of rock, hurtling through space at tens of thousands of miles per hour. You can't go on playing a game of chance and expect to keep winning. Our solar system is full of deadly missiles that could strike at any time. ![]()
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