Cosmic Journeys - Day of the Asteroid

we look out into space to experience a sense of peace and wonder but how much do we really know about what's out there asteroids racing through the solar system have smashed into Earth before what are the chances we'll get him again armed with new generation technologies and daring new concepts scientists are getting ready for the inevitable day a decade century or millennia from now per day of the asteroid scientists and philosophers once believed the universe worked as a precision instrument designed by the ultimate watchmaker God the world around us moves in neverending cycles the seasons a bang and flowed planets and moons circling the Sun stars drifting across the night sky all the Testaments to the perfection of creation scientific discoveries challenged this view the working of natural laws in chemistry physics biology gradually replaced the tinkering of an intelligent designer we've learned that the universe is shaped by violent events stars exploding in a fury galaxies tearing each other apart black holes emitting powerful streams of energy even our own peaceful world was born in violence astronauts walking on the lunar surface found rocks uncannily similar to those on earth that led to the idea that the two were formed in a planetary collision early in the history of the solar system the craters that pock the lunar surface record a history of ongoing impacts earth has not been spared this pounding the fact is that our solar system is still stopped with countless sub planet-sized objects some lion stable orbits as in the asteroid belt between Mars and Jupiter others follow looping orbits that intersect with Earth's own path over the years they have continued to strike our planet often leaving marks that we can see and ponder of the 175 known impact sites meteor crater is perhaps the best preserved it dates back to a day some 50,000 years ago when a nickel-iron asteroid slammed into Arizona at 30 to 40 meters wide and a mass of 300,000 tons it left a crater almost 200 meters deep this is the penguin Lewis crater in Quebec created 1.3 million years ago the impactor is thought to have unleashed the energy of over 8,000 Hiroshima sized atomic bombs it left a crater three-and-a-half kilometers wide and 400 meters deep the manticore Gong crater known as the eye of Quebec was left by a five kilometer wide asteroid some 214 million years ago it may have been part of a chain of impacts that struck in what are now France Ukraine and North Dakota it would have been similar to the string of fragments from the shoemaker-levy comet that struck Jupiter in 1994 the largest known impact crater can be found in South Africa known as the vredefort crater it's about 2 billion years old what you see here is the inner crater the impactor blasted out a 300 kilometer wide grater spreading devastation across the region it was part of a class of large impacts capable of wreaking havoc all around the globe just recently scientists discovered what appears to be a large impact basin on the east coast of Antarctica they proposed that the impact sent shockwaves through the planet triggering the eruption of a giant volcanic hotspot on the planet opposing or antipodal side that eruption is linked to the greatest mass extinction on record including 96% of all marine species at the end of the Permian period about 252 million years ago then there's the Chicxulub crater straddling Mexico's Yucatan Peninsula the asteroid was at least 10 kilometers in diameter the debris thrown into the upper atmosphere has been blamed for the extinction of all non-avian dinosaurs in the last few decades studies of impacts have led to a new sense of awareness that earth remains vulnerable it's not only the danger of a city ending up at the bottom of a crater it's what happens when an incoming asteroid doesn't even reach the ground just after sunrise February 15 2013 residents of Chelyabinsk in southern Russia were greeted by a stunning aerial display 23 kilometers above the town a streaking meteor exploded with the equivalent of 500 kilotons of TNT or 20 to 30 per Oshima bombs over a thousand peaceful religions but most from falling debris and flying grass three and a half hours later the polar orbiting Suomi satellite began tracking the plume of dust and smoke from the explosion over the next four days scientists tracked the plume as it spread out in high-altitude winds forming a complete global belt they further studied its motions with computer models in an effort that could one day help predict the atmospheric effects of incoming asteroids the Chelyabinsk explosion was reminiscent of one of the most famous asteroid impacts in modern times but Raguse Castrol simulated in these sequences exploded over Siberia in 1908 leveling 2,000 square kilometres including 80 million trees what if an asteroid this size took aim at London or New York or any of the world's metropolitan areas one group of scientists and celebrities believes our first line of defense is simple awareness and a sense of urgency they are promoting asteroid day June 30 on the anniversary of Tunguska to remind us all that the clock may well be ticking down to the next asteroid disaster asteroid day has captured the imagination of many for its cause for expanded monitoring and science initiatives spiced with select promotion it's also drawn criticism for its appeals to fear and for what some see as exaggerated doomsday scenarios so how real is the threat and is there anything we can do about it 1998 the blockbuster movie Armageddon sent a comet on a beeline for Earth a heroic food travels out to meet it landing on its surface they drill a hole large enough to plant a nuclear bomb their sacrifice is rewarded the planet is safe earth doesn't get off so easy in deep impact released the same year this time the rescue proof fails to destroy the incoming come blasting it instead into two projectiles one hits the Atlantic Ocean the lucky ones head for the hills that same year the US Congress directed NASA to begin discovering and tracking near-earth objects those with orbits that could overlap ours or that come within 1.3 times the distance from the earth to the Sun astronomers have since identified over 13,000 objects and are adding 1,500 new ones to the list each year that includes some 90% of all those expected to be in the kilometer class or larger according to the data there are no large asteroids on a collision course with earth in the foreseeable future in fact our chances of being hit by one of the dinosaur killers at least 10 kilometers across amount - once every 100 million years the chances of being hit by a one kilometer asteroid rise - once every seven hundred thousand years six hundred and three hundred meter rocks should hit every 200 thousand and seventy thousand years bringing continent scale devastation its every twenty thousand years for 140 meter objects and every three hundred years for 40 metre objects like the one that punched a hole in Arizona or that blew up over two Agusta large asteroids can still come uncomfortably close take the so called Halloween asteroid also known as 2015 TB one four five this massive object six hundred meters in diameter flew within five hundred thousand kilometers of Earth for about one point three times the distance from Earth to the Moon it arrived just three weeks after it was discovered the fact of the matter is that we still don't have a complete handle on the asteroid threat as a result NASA recently began to shift its attention to smaller objects down to about 140 meters wide of which perhaps only about 10% are currently known NASA's wise satellite has been recommissioned as NEOWISE to search for near-earth objects the prolific asteroid finding pan-starrs telescope in Hawaii has been upgraded additional projects are joining the search Atlas is a series of small telescopes to be deployed around the world with large camera sensors designed to detect dangerous incoming asteroids looking down the road NASA is mounting what it calls the asteroid Grand Challenge it will seek a variety of government corporate and citizen partnerships to detect track and stop all potentially hazardous asteroids planetary defense is no longer just the subject of action movies the European Space Agency ESA and NASA are planning a joint project to test the idea of actually altering an asteroids path ESA's asteroid impact mission aim will target a binary asteroid system called six five eight or three didymus the spacecraft would orbit the pair to collect a range of data that includes releasing tiny landers called cube SATs to collect specialized information a massive craft called dart would arrive laser this vehicle would ran into the smaller 150 meter asteroid the impact should lead to a significant change in its orbit around its 800 meter companion while this would not affect this pairs trajectory through the solar system it would provide information on what it would take to alter the course of an object that might one day threaten earth NASA's ambitious asteroid redirect mission arm takes a different approach the spacecraft would slowly orbit the asteroid scanning its surface for landing zones and for boulders commonly found on asteroid surfaces it will then descend to the surface deploying a pair of specialized claws that will clamp onto a targeted boulder rising up with rock in hand the spacecraft will move into a position near the asteroid the idea is to use its gravitational attraction to subtly deflect the asteroid from its earth-crossing path the arm mission has a potential side benefit the craft may be used to deliver the boulder to lunar orbit where astronauts can get their hands on it and return samples to earth plans to mitigate the threat of near-earth asteroids coincide with rising interest in what they have to offer us you the osiris-rex spacecraft is one of a range of missions proposed by governments and private ventures it's scheduled to travel out to the asteroid 101 nine five five demo and return by the Year 2023 with rock and dirt samples scientists want to know what can be as tiny ancient worlds tell us about the early days of the solar system four to five billion years ago what we're minerals can future asteroid mining missions tap into and what role can asteroids play in future human missions to explore and colonize the solar system in this age of rapid advances in science and technology we are gaining a firmer grasp of Earth's larger space environment both the resources and the threats these same advancements are allowing us to understand the course of earth and humanity on longer and longer timescales will we be ready when the inevitable arrives a decade the century or a millennium from the day of the asteroid

Channel: SpaceRip

Views: 441,555

Rating: 4.6973386 out of 5

Keywords: solar system, asteroid, comet, nasa, planet, impact, dinosaurs, crater, meteor, science, astronomy, telescope, spacecraft, Armageddon, Deep Impact, asteroid day, extinction, permian, tunguska, jupiter, mars, cosmic journeys

Id: AO-gegCmRpQ

Length: 25min 17sec (1517 seconds)

Published: Fri May 20 2016