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Asteroids are much harder to destroy than scientists originally thought

first_imgThe options are limited. SCIEPRO Nuking an asteroid out of the sky to protect the Earth is great fodder for the silver screen. However, new research suggests that simply blowing up a threatening space rock may not save us quite as simply as we might hope. Scientists find rogue asteroids roaming our solar system often — just last month they discovered yet another one that could (maybe) strike the Earth. One of the ways to deal with these potential threats is to impact them, knocking them off course. NASA is currently planning an asteroid redirect mission where it’ll send a kamikaze spacecraft into the moonlet of an asteroid known as Didymos, barreling into the rock to shoo it away.Yet we haven’t had a lot of opportunities to study asteroids up close, so we can’t appreciate exactly how they are structured or how they might be destroyed. It has been believed that bigger asteroids may be easier to destroy because they would be more likely to have cracks and weaknesses that make them easy to blow apart. Thus, if an asteroid were to threaten our peaceful existence, what should we do?”Are we better off breaking it into small pieces, or nudging it to go a different direction? And if the latter, how much force should we hit it with to move it away without causing it to break?” asks Charles El Mir, lead author on the study, in a press release. Those questions are exactly what he and a team at Johns Hopkins University set out to answer.In the simulation, an asteroid splits apart but is pulled back together by the effect of gravity. This animation is sped up — this phase occurs over many hours. Johns Hopkins University/YouTube Their findings, published in an upcoming issue of the journal Icarus, are based on computer simulations of asteroid impacts. They plugged in parameters that digitally recapitulated a small asteroid, about 1 kilometer wide, impacting a large asteroid, about 25 times bigger, while travelling at 5 kilometers per second.A previous model had shown that the large asteroid was obliterated by this type of collision — but the Johns Hopkins team found an entirely different endgame. According to their modelling, the asteroid would greatly fracture in the fractions of a second after an impact.Over the hours after an impact though, the team showed the large asteroid broke apart into smaller pieces but wasn’t entirely obliterated as previous research had shown. The fragments that flew off the asteroid were then pulled back together by the damaged asteroid core, due to the overwhelming effect of gravity.Thanks, gravity.”We used to believe that the larger the object, the more easily it would break, because bigger objects are more likely to have flaws,” said El Mir. “Our findings, however, show that asteroids are stronger than we used to think and require more energy to be completely shattered.”The strength of the asteroid to resist such an impact allows it to preserve its gravitational pull, which could wreak havoc if we were to blindly fire rockets at an incoming rock. Understanding these interactions better prepare us for the decisions that will have to be made, should an asteroid be set on colliding with the Earth.Originally published March 6 at 7:13 p.m. PTUpdate, March 7 at 1:15 a.m.: Clarifies earlier experiment. Share your voice 1 Commentcenter_img Tags Sci-Techlast_img read more

Volunteers need umbrella org for effective disaster response

first_imgSpeakers at a roundtable on `Institutionalisation of Urban Community Volunteers` organised by Prothom Alo in association with Social and Economic Enhancement Programme (SEEP) of Save the Children at the daily’s Karwan Bazar office on Wednesday. Photo: Abdus SalamUrban planners and people concerned at a roundtable on Wednesday said volunteers at the urban level of disaster management need to be brought under one umbrella organisation in order to ensure effective and prompt response to disasters.The roundtable styled “Institutionalisation of Urban Community Volunteers” was organised by Prothom Alo in association with Social and Economic Enhancement Programme (SEEP) of Save the Children at the daily’s Karwan Bazar office in the capital.Speakers highlighted various aspects and obstacles of disaster management, especially in at an urban level.Citing the difference between coastal and urban disaster management, they said volunteers working in urban areas needed different training and technical support.Although many NGOs conducting different training programmes for volunteers, most of them are ad hoc or project- based. When their training project ends, the volunteers do not have proper guidelines about their service that leads them to drop out in many cases. Institutionalising community volunteers would make their services well-organised.The discussants said the Bangladesh government is committed to train 62,000 community volunteers as the densely populated nation is highly susceptible to earthquakes.Emphasising the issue of awareness building, the disaster management and relief ministry’s additional secretary Satya Brata Saha said a nation needs a vision for development.The discussants suggested initiatives to create awareness about the disaster management among people through TV programmes, community radio and street plays.The Cyclone Preparedness Programme (CPP) conducts training, seminars, street plays and campaigns to raise awareness on disaster management.Speakers at a roundtable on `Institutionalisation of Urban Community Volunteers` organised by Prothom Alo in association with Social and Economic Enhancement Programme (SEEP) of Save the Children at the daily’s Karwan Bazar office on Wednesday. Photo: Abdus SalamThe discussants said a single agency should take all the responsibilities for the urban community volunteers with particular roles. The agency should be strengthened so that they can lead efficiently during any disaster.Describing community as the worst sufferer and first responder during any disaster, director general at Bangladesh Fire Service and Civil Defence brigadier general Ali Ahmed Khan said, “Trained volunteers are assets for any society.” Bangladesh Fire Service and Civil Defence have already trained up 33000 volunteers with the financial support of Comprehensive Disaster Management Programme, he mentioned.Ali Ahmed Khan said, “The fire service in association with community volunteers can build up a sustainable force “.He said the fire service maintained a manual database not a digital one. So they faced difficulties to find volunteers during a fire. Besides they couldn’t share their database with the city corporations, the municipality and other offices in the district level so that they could get help from the volunteers.Praising Prothom Alo’s initiative, chairman of the parliamentary standing committee on relief and disaster management Dhirendra Debnath Shambhu said, “The government is currently working on building an umbrella organisation for all the volunteer groups.”Disaster being a barrier to development, disaster management needs to be more effective and up to the standard to achieve the Sustainable Development Goals, he said.Trained volunteers Mohammed Wahid and Mohammed Shaheed Alam, director general of Disaster Management Directorate Md Reaz Ahmed, director (admin) of CPP Ahmadul Haque and director of Programme Development and Quality at Save the Children Reefat Bin Sattar and other also spoke at the roundtable.Prothom Alo associate editor Abdul Quayum moderated it.last_img

UPDATE Melania Trump Travels To Arizona To Visit A Migrant Facility

first_img Share AP Photo/Carolyn KasterFirst lady Melania Trump arrives at Davis Monthan Air Force Base, Thursday, June 28, 2018, en route to a U.S. Customs border and protection facility in Tucson, Ariz.First Lady Melania Trump is paying a second visit to children detained under her husband’s “Zero Tolerance” policy for illegal border crossings. She arrived at Tucson, Ariz., where she will visit a Customs and Border Protection facility and participate in a roundtable discussion with Border Patrol, Immigration and Customs Enforcement, the U.S. Marshals Service and a local rancher.The trip follows a visit last week to the border town of McAllen, Texas to a shelter for children separated from their parents.“She wanted to see everything for herself,” her spokeswoman, Stephanie Grisham, said at the time. “She supports family reunification. She thinks that it’s important that children stay with their families.”Grisham confirmed on Tuesday that a second trip was being planned, but details were kept under wraps.During the trip to McAllen, the first lady’s choice of a jacket emblazoned with the words, “I REALLY DON’T CARE, DO U?” prompted controversy and speculation about its meaning. Her spokeswoman said it was simply “a jacket” with “no hidden message.”She did not wear the jacket Thursday.The initial trip took place the day after President Trump signed an executive order aimed at ending family separations. A White House official told NPR that Melania Trump pressed her husband to stop separating children from their parents.On Tuesday, a federal judge in San Diego ordered the administration to stop separating parents and children and said that all immigrant children detained under the Trump administration policy must be returned to their parents within 30 days.Since the ruling, Grisham said Thursday, the first lady is “anxious to learn how they’re implementing the new process. There was a court case that threw a wrench in the works.”last_img read more