first_img Citation: Research shows collision created Chelyabinsk asteroid (2014, May 23) retrieved 18 August 2019 from https://phys.org/news/2014-05-collision-chelyabinsk-asteroid.html (Phys.org) —On February 15 2013, an asteroid exploded about 30 kilometers above Chelyabinsk, Russia. The explosion, shared on video around the world, was the Earth’s second largest recorded airburst. By analyzing fragments of the meteorite that fell to Earth, Shin Ozawa at Tohoku University in Sendai, Japan and colleagues determined that the asteroid formed when a parent asteroid collided with another asteroid and then broke apart. The research appears in Scientific Reports. © 2014 Phys.org Insight into space collisions from Chelyabinsk fireball More information: Jadeite in Chelyabinsk meteorite and the nature of an impact event on its parent body, Scientific Reports 4, Article number: 5033 DOI: 10.1038/srep05033AbstractThe Chelyabinsk asteroid impact is the second largest asteroid airburst in our recorded history. To prepare for a potential threat from asteroid impacts, it is important to understand the nature and formational history of Near-Earth Objects (NEOs) like Chelyabinsk asteroid. In orbital evolution of an asteroid, collision with other asteroids is a key process. Here, we show the existence of a high-pressure mineral jadeite in shock-melt veins of Chelyabinsk meteorite. Based on the mineral assemblage and calculated solidification time of the shock-melt veins, the equilibrium shock pressure and its duration were estimated to be at least 3–12 GPa and longer than 70 ms, respectively. This suggests that an impactor larger than 0.15–0.19 km in diameter collided with the Chelyabinsk parent body at a speed of at least 0.4–1.5 km/s. This impact might have separated the Chelyabinsk asteroid from its parent body and delivered it to the Earth. Journal information: Scientific Reportscenter_img (a) The host-rock showing an equilibrated chondrite texture. (b) A shock-melt vein cutting through the host-rock. The two white dotted lines represent the boundaries between them. (c) Coarse-grained fragments and fine-grained matrix in a shock-melt vein. (d) Enlarged view of the area shown by the white rectangular in (c). Needle-like and skeletal-rhombic crystals of jadeite occur with feldspathic glass. Ol = olivine, En = enstatite, Di = diopside, Fsp = albitic feldspar, Me = Fe–Ni metal, Tro = troilite, Chr = chromite, SMV = shock-melt vein, Mtx = matrix of shock-melt vein, Jd = jadeite, Gl = feldspathic glass. Credit: Scientific Reports 4, Article number: 5033 doi:10.1038/srep05033 When an asteroid, 17 to 20 meters in diameter, burst over the south of Chelyabinsk city, in Russia’s southern Ural region, it generated shockwaves that injured more than 1000 people and damaged many buildings. Unlike many other Near Earth Objects (NEOs), the Chelyabinsk asteroid had a well-recorded trajectory, and it left fragments on the Earth. This gave scientists a unique opportunity to study its formation.Previous studies of the asteroid’s fragments had shown they contain shock-melt veins, which form when heat and pressure from an impact cause materials in a section of an asteroid to melt. Eventually, shock-melt veins lose heat to cooler surrounding rock and solidify, forming glassy structures.Ozawa’s team examined the shock-melt veins in the Chelyabinsk fragments and found they contain the mineral jadeite, which forms under extremely high pressure. Some terrestrial rocks and meteorites contain jadeite. However, when the team examined the jadeite from the Chelyabinsk meteorite under an electron microscope, they found the mineral had a unique composition and structure that indicated it had crystallized very rapidly.By calculating the rate at which the jadeite must have solidified, the team were able to determine that the asteroid must have formed when a parent asteroid collided with a second asteroid, which was at least 150 meters in diameter and moving at a relative speed of 0.4 to 1.5 kilometers per second. A previous study of the isotopes in the meteorite had shown that a collision could have occurred up to 290 million years ago. The jadeite would have formed as the result of this collision, as the mineral would not have survived a later impact. Earlier calculations had shown that asteroids in the main asteroid belt have lifetimes of less than 10 million years. The researchers think the Chelyabinsk asteroid broke off from its parent after the collision and moved into an orbital resonance less than 10 million years ago. It then fell into an orbit crossing that of the Earth.The research increases our understanding of how NEOs form and evolve. It shows that NEOs, which have the potential to strike the Earth, can survive much longer than previously believed. 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. Explore furtherlast_img

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first_img About Howard Lake Howard Lake is a digital fundraising entrepreneur. Publisher of UK Fundraising, the world’s first web resource for professional fundraisers, since 1994. Trainer and consultant in digital fundraising. Founder of Fundraising Camp and co-founder of GoodJobs.org.uk. Researching massive growth in giving. Tagged with: Gift Aid HMRC legacies HMRC has published a guide on payroll giving and Gift Aid for school charities, designed to help them understand how they can make the most of these methods of tax-effective giving.‘Gift Aid & Payroll Giving: a reference guide for school charities’ features a summary of how Gift Aid and Payroll Giving work and which donations qualify.It also covers examples of funds received by school charities and explains which qualify for Gift Aid. These include:• Appeals to fund extra lessons• Non-uniform days• Schools fees• Appeals towards school running costs• Appeals to fund scholarships• Appeals to a general reserve fund• Educational school trips• Appeals to buy a minibus or other equipment• Sponsored events• Payments to e-Learning Foundations• Building appeals• Other fundraising eventsGift Aid & Payroll Giving: a reference guide for school charities is available as a free PDF download.www.hmrc.gov.uk/charities/gift_aid/rules/school-charities.htm Payroll giving and Gift Aid guide for schools published  44 total views,  2 views today AddThis Sharing ButtonsShare to TwitterTwitterShare to FacebookFacebookShare to LinkedInLinkedInShare to EmailEmailShare to WhatsAppWhatsAppShare to MessengerMessengerShare to MoreAddThis AddThis Sharing ButtonsShare to TwitterTwitterShare to FacebookFacebookShare to LinkedInLinkedInShare to EmailEmailShare to WhatsAppWhatsAppShare to MessengerMessengerShare to MoreAddThis Howard Lake | 15 September 2011 | Newslast_img

first_img SHARE After hosting what the White House initially called a “listening” session, President Donald Trump took American investors by surprise Thursday. Trump announced to the group attending the meeting that he will be imposing the long-rumored steel and aluminum tariffs next week. The president will impose a 25 percent tariff on steel imports and a 10 percent for aluminum. Trump told a meeting of steel and aluminum executives that he’ll sign the paperwork next week. “You’re going to have protection for the first time in a long time,” he said to the executives. He says steel and aluminum workers haven’t been represented in some time and moves like this will help rebuild the American industries.Before making the announcement, Trump praised his recent tariffs on solar panels and washing machines, saying they were a good example of how tariffs can lead to investment in different U.S. business sectors. Metal company stocks rose sharply after the midday announcement. At the same time, the announcement pushed the Canadian dollar sharply lower. While it did bounce back somewhat, the tariffs remind people on both sides of the border about lingering tensions as the countries continue to participate in NAFTA negotiations.U.S. Wheat Associates and the National Association of Wheat Growers were both very disappointed in the Trump Administration’s decision to impose tariffs on steel and aluminum imports. A statement says they have repeatedly warned of the risks of retaliation and the precedent set by such a policy would have potentially serious consequences for agriculture. The groups say it’s disappointing that the voices of farmers and many other industries were ignored in favor of an industry that’s already among the most well-protected in the country.Brian Kuehl of the Farmers for Free Trade Organization says they are also deeply concerned that the move to impose tariffs will unintentionally hurt American agriculture. “These tariffs are very likely to accelerate a tit-for-tat approach on trade, putting U.S. agricultural exports in the crosshairs,” Kuehl says. “We’ve already seen China discussing tariffs on sorghum, while the EU and China have both indicated they will move forward with swift retaliation in the wake of these tariffs.” He adds that everyone agrees on the need to hold trading partners accountable but taking unilateral action like this will have unintended consequences. “The ag sector knows from experience that our ag exports are the first to be hit by retaliation,” he adds. SHARE Home Indiana Agriculture News Trump Will Impose New Tariffs on Steel and Aluminum Trump Will Impose New Tariffs on Steel and Aluminum Facebook Twitter Facebook Twitter By NAFB News Service – Mar 2, 2018 Previous articleReactions to White House RFS MeetingsNext articleRyan Martin’s Indiana Ag Forecast for March 2, 2018 NAFB News Servicelast_img

first_imgLinkedin + posts printWhile the exterior of TCU’s Greek housing has a cohesive style to match the rest of campus, each sorority was given the liberty to personalize its interior as it pleased with the help of alumni and other board members. TCU funded the majority of the project but allowed the chapters to purchase upgrades and personalize their houses with design elements.Many sororities incorporated their traditions and symbols into their designs; Kappa Kappa Gamma is clad in blue and blue, two lions guard Alpha Delta Pi’s entrance and Delta Gamma has an anchor rooted in their front yard.  The new houses don’t just have personal touches though, many sorority women living in the houses said the new open chapter rooms and kitchens have allowed bonding opportunities with sisters. This is something you don’t get to do in a regular dorm, sophomore Kappa Alpha Theta member, Hailey Paul said.“Theta’s study room has comfy chairs and couches that are inviting and make all of us want to sit in there to have a social gathering to be able to help each other with school, as well as catch up on life,” Paul said.The chapter room is furnished with tables that allow Theta members to eat together like a family with comfortable couches nearby for sometimes watching a movie after dinner, Paul said.Interior of Kappa Alpha Theta’s house.“Elizabeth White, the designer, was so cool and helped us make the chapter room super cute and welcoming,” Paul said. The chapter had a huge part in this project and is one of its biggest supporters, White said.Over at the Delta Gamma house, there is a similarly positive response.“Walking into the Delta Gamma house instantly feels like home,” Sophomore Delta Gamma member Rachael Reinhert said. “There is a loving sense within the walls. The light pink brings friendship, peace while the blue brings trust. We share this space between the light cream walls as friends and as family.”  Interior of Delta Gamma’s sorority house.Delta Gamma received help from alumni member Lisa Ford to design the beautiful house they have now, said Reinhert. Ford said she enjoyed designing the interior to match the traditions and customs of this special group of women.  TCU places second in the National Student Advertising Competition, the highest in school history Facebook ReddIt Never too young to make an impact Twitter Welcome TCU Class of 2025 Colleen Powell Study abroad adds Stellenbosch, South Africa to its list of destinations ReddIt Colleen Powellhttps://www.tcu360.com/author/colleen-powell/ Colleen Powellhttps://www.tcu360.com/author/colleen-powell/ Previous articlePrimary election shows surge in voters for Democratic candidatesNext articleHoroscope: March 7, 2018 Colleen Powell RELATED ARTICLESMORE FROM AUTHOR Facebook Colleen Powellhttps://www.tcu360.com/author/colleen-powell/ Linkedin Twitter Colleen Powellhttps://www.tcu360.com/author/colleen-powell/ Fort Worth Music Festival World Oceans Day shines spotlight on marine plastic pollution Eco-Friendly hair salons look to encourage others to help the environmentlast_img

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