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What Issues Will Shape The 2019 Houston Mayors Race

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Spacecraft Could Save Earth from Asteroids

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first_img(PhysOrg.com) — British space engineers working for a space company in Stevenage in England, have designed a “gravity tractor” spacecraft to deflect any asteroids threatening to collide with Earth. The announcement comes only weeks after an asteroid collision scar around the size of Earth was detected on Jupiter. Explore further This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Asteroid (2867) Steins. Image: ESA Citation: Spacecraft Could Save Earth from Asteroids (2009, September 4) retrieved 18 August 2019 from https://phys.org/news/2009-09-spacecraft-earth-asteroids.html A collision with an asteroid is a rare event, but scientists believe it is inevitable that sooner or later an asteroid will come close enough to be a real threat. In fact in 2004 an asteroid called Apophis caused alarm when scientists predicted there was a 1:37 chance of it hitting Earth in 2029, which is the greatest threat in recorded history. They later revised their figures but it could still be on course to collide in 2036. The US space agency, NASA estimates there are at least 1000 “potentially hazardous asteroids.”NASA is so concerned about the threat it has set up a monitoring program to track every space object that could be an asteroid on a collision course. They are so far tracking over 6,000 asteroids whose orbits bring them close to Earth, but there are an estimated 100,000 asteroids large enough to wipe out a city.A collision could be catastrophic, depending on how large the asteroid is and where it hits. A direct hit to a city by even a relatively small asteroid the size of a football field, for example, could completely destroy the city and kill millions of people. Many more could be killed by tsunamis triggered by the impact, and by dust and burning material thrown up into the atmosphere after the collision.The engineers, led by Dr Ralph Cordey, head of exploration and business at EADS Astrium, a British space company, have designed what they call a “gravity tractor”, a ten-tonne spacecraft around 100 feet long that could provide a practical way of averting a collision with Earth. The device would be launched as soon as an asteroid was found to be on course to crash into the planet, and would fly alongside it at a distance of about 160 feet away. The craft could divert an asteroid up to 430 yards in diameter, and an impact with an asteroid this size would release around 100,000 times the energy of the bomb dropped on Hiroshima in 1945.The gravity tractor is designed to draw the asteroid towards itself by exerting a small gravitational force on it. The spacecraft would then steer the asteroid away into an orbit away from Earth. The craft would use four ion thrusters, which are low energy and efficient, of the type commonly used on deep space probes. The ion thrusters enable the craft to adjust its position relative to the asteroid. The gravitational pull exerted by the asteroid would be enough to nudge the rock into a different, and less dangerous, trajectory.The process of steering the asteroid away from a collision course would take several years, with the craft changing the angle of trajectory by only a fraction of an inch over 15 years, but that is enough change to divert an asteroid. The spacecraft would need to be launched at least 15 (preferably 20) years before the predicted collision to give it time to adjust the asteroid’s trajectory away from Earth.The design team say the gravity tractor could be built fairly quickly with existing technologies, although a prototype has not yet been built. They have planned the details of the mission, and expect the cost could be shared by a number of governments if an asteroid on track to hit Earth was discovered, and international agreements would need to be drawn up.NASA published a paper earlier this year on the feasibility of using a gravity tractor for this purpose, and they concluded it could be extremely effective if there was enough warning. With scientists saying the asteroid Apophis could possibly be on a course to collide with Earth in 2036, perhaps we do have enough warning.© 2009 PhysOrg.com NASA Statement on Student Asteroid Calculationslast_img read more

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Youth shot dead by cousin brother over family dispute

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first_imgKolkata: A youth from Diamond Harbour was allegedly shot dead by his cousin brother over some dispute.The incident took place in the Netra area of Diamond Harbour area in South 24-Parganas on Monday night. The victim has been identified as Sabbir Gaji. The victim went to a fair near Diamond Harbour station on Monday evening. After visiting the fair, the victim was going to one of his relatives’ houses situated nearby. When Gaji was about to enter the house of his relative, his cousin brother Rakibul Gaji turned up there and took him to a house in the locality. Also Read – Rain batters Kolkata, cripples normal lifeAfter a few minutes the youths stepped into the room, locals heard the sound of a gunshot. They rushed to the spot only to find the victim lying in a pool of blood. The victim with a bullet injury was taken to Diamond Harbour District Hospital and was later shifted to a city hospital as his condition deteriorated. The patient succumbed to his injury on late Monday night. The incident triggered panic among locals residents in the Netra area. The family members of the victim lodged a complaint at the local police station against the cousin brother, Rakibul, and four others. On the basis of the complaint police have started a probe. They are yet to ascertain the exact cause that might have led to the murder. According to the preliminary investigation, police suspect that some family-related dispute might have caused the incident. Cops are investigating if the victim had any personal rivalry with his cousin brother. The investigating officers are interrogating the family members of the victim and police are conducting raids to nab the accused.last_img read more

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Driver taken to hospital after van collides with house

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No major damage after Willa says Puerto Vallarta

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first_img Posted by Share Tags: Hurricane Willa, Puerto Vallarta PUERTO VALLARTA — Following the passage of Hurricane Willa earlier this week, Puerto Vallarta has announced that operations are returning to normal.After an extensive evaluation of the city by the Civil Protection and Fire Department, it was determined that the risk of storm surges and winds has been significantly decreased, and that Puerto Vallarta’s tourism infrastructure was left with no major damage. This includes: Licendiado Gustavo Díaz Ordaz International Airport, which has remained open; trans-national roads; and the marina, cruise port, and Pier Los Muertos, which provides access to areas south of Puerto Vallarta such as Yelapa.City services will also be back to normal, including schools and garbage collection. Cleaning crews and public works and public services personnel have begun clearing debris left by high winds and waves.According to Adrian Bobadilla, head of Civil Protection and Puerto Vallarta’s Fire Department, a total of 587 tourists and 62 locals were housed in city shelters because they were in high-risk areas, mostly around local bodies of water. He also mentioned that many locals opted to stay with family members while some hotels conducted voluntary evacuations according to their own contingency plans.More news:  Honolulu authorities investigate arsons at 3 Waikiki hotels; no injuries reportedHurricane Willa briefly reached Category 5 strength on Monday, with winds of 260 kph, before weakening to Category 4. Officials said up to 8,000 people were evacuated from low-lying areas, mostly in Sinaloa state. Friday, October 26, 2018 center_img Travelweek Group No major damage after Willa, says Puerto Vallarta << Previous PostNext Post >>last_img read more

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