![]() The main food source for sperm whales are medium sized squid (0.5 m and 1–3 kg), of which 70–80% are slow moving, ammoniacal species 4, 5, while the remainder are faster moving squid and fish targeted at meso- and epipelagic depths 6, 7, 8. Sperm whales are mainly teuthophagous predators that spend more than half of their life below 500 meters depth where they target meso- and benthopelagic prey. Today, almost 200 years later, that question is still relevant for the largest tooth-bearing predator on the planet, a major nutrient recycler in the world’s oceans 2 responsible for an annual biomass turnover that has been compared to the combined catches of human fisheries 3. “ It remains, then, to be inquired in what way the sperm whale (Physeter macrocephalus) usually does supply his enormous frame with sufficient food” wrote the whaling surgeon Beale in 1840 1. The high temporal resolution helps to guide motor patterns during occasionally prolonged chases in which prey are eventually subdued with the aid of fast jaw movements and/or buccal suction as indicated by acceleration transients (jerks) near the end of buzzes. Rather, buzzing involves high-frequency, low amplitude clicks well suited to provide high-resolution biosonar updates during the last stages of capture. As a result, received levels at the prey are more than an order of magnitude below levels required for debilitation, precluding acoustic stunning to facilitate prey capture. We show that in the terminal buzz phase, sperm whales reduce inter-click intervals and estimated source levels by 1–2 orders of magnitude. Here we test these hypotheses by using sound and movement recording tags in a fine-scale study of buzz sequences to relate the acoustic behaviour of sperm whales with changes in acceleration in their head region during prey capture attempts. ![]() Several hypotheses have been advanced to propose both active and passive means to acquire prey, including acoustic debilitation of prey with very powerful clicks. However, it remains a conundrum how this bizarrely shaped apex predator catches its prey. The sperm whale carries a hypertrophied nose that generates powerful clicks for long-range echolocation.
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Now you want to pull the string gently downward with one hand. Sometimes, even if you think everything looks great in the air, you may notice that the kite feels a little sluggish and the line is sagging. Your kite may begin an unsteady descent until you pull back on the string with one hand, which should boost its stability again. If you let the string out too much, its weight will actually begin pulling the kite down. If you see the kite swooping in different directions and feel it tugging your string, it’s time to pay out the line. Make sure you pull the line as your friend lets go. If there’s enough wind, the kite will take flight. As you hold on to the spool, tell your friend to throw the kite straight up in the air. Have the friend hold the kite and spool out string for several feet, making sure it’s straight. If you have a friend to help, you can team up to give your kite a boost. Roll out about 50 feet of string from your kite and walk back until the line is as straight as possible, according to Jim Nicholls’ 1,508th kite video. You can employ a “long-line launch” if you’re having trouble. When you feel the kite pulling away from you as it catches an updraft, let your string spool out a bit. ![]() Now let go of the kite and grasp the spool with both hands. You’ll notice that the kite is already picking up the breeze. ![]() Hold the kite in your non-dominant hand and the spool in the other. The beach is always a good option when choosing a location for flying a kite, because it usually has a strong offshore breeze. If your kite has tails, pay attention to what direction they are blowing, because they’re an indicator of wind direction. Avoid going out in stormy weather too, in case of lightning strikes. Flying near trees and power lines is a bad idea. Choose a location that has a quarter to half a mile of clear space behind you, according to kite enthusiast Chris Maxa, who demonstrates how to fly a kite. That way, when you let go of your kite, you can keep an eye on it as it rises in front of you. These Are the 13 Biggest Planes in the WorldĪ good rule of thumb is to start your flight with the wind at your back.The feel of the tautness in the line, the jerk of the kite as it struggles to maintain its orientation in an uncertain wind, and the sight of kite tails pointing in the breeze, indicate what to do next. Of course, nobody flies a kite with a pad and pencil to determine the physics of the moment, so these principles are learned through experience. That means lift must equal the weight of the kite, and thrust by the wind must be equal to drag, the kite’s resistance to movement through the air. Once it’s airborne, you have to keep the four forces in balance so your kite continues to fly smoothly. To launch a kite into the air, the force of the initial lift must be greater than the kite’s weight. Whether you’re handling a jumbo jet or a kite, aerodynamic forces rule all flying objects. With the help of some popular YouTube explainers, here are the basic steps for how to fly a kite with minimum stress and more enjoyment! How to Launch Your Kite □ Hundreds of birds also fly into the kite strings or are entangled in them, causing deep cuts to their wings, nerve injuries, fractures, dislocations and, in many cases, death.Play icon The triangle icon that indicates to play □ You love learning new skills. The popular festival marks the onset of spring where kite-flying is often used during celebrations across the country. If the official ban is not being implemented, then the government should offer compensation to victims,” the Times of India quoted Shinde as saying. “Citizens should not have to pay for the lackadaisical attitude of the government machinery. However, Jayesh Shinde, an activist campaigning against the use of manja, said the government had failed to uphold the ban and should compensate victims for their treatment. Police urged participants to be careful while flying kites during the festival, saying the “momentary fun” of cutting another kite could come at the cost of someone’s life. “Do not use deadly Chinese manja to fly kites,” it said. In Ahmedabad, Gujarat’s largest city, the police department warned against using the coated kites at the festival. ![]() Photograph: Saurabh Sirohiya/Zuma/Rex/Shutterstock Some participants use strings coated with glue and mixed with powdered glass to enable flyers to cut those of rivals. A kite trader in a backstreet in Ahmedabad sells colourful kites. Later this month, the probe, which is low on fuel, will begin the "grand finale" phase of its mission - a series of 22 orbits that will take it between Saturn's cloud tops and the edge of the innermost ring. (Huygens was a piggyback lander that touched down on the surface of the huge Saturn moon Titan in January 2005.)īut the Cassini orbiter's work is nearly done. The $3.2 billion Cassini-Huygens mission - a joint effort of NASA, the European Space Agency and the Italian Space Agency - launched in October 1997 and arrived at Saturn in July 2004. (Image credit: NASA/JPL-Caltech/Space Science Institute) Cassini got some passing images of Atlas in 2015, but it’s unlikely the space probe will have time to do a more in-depth photo shoot with that moon before the probe’s final mission: crashing into the surface of Saturn in September, 2017.Saturn's moon Atlas hangs in the void in this image taken by NASA's Cassini spacecraft on April 12, 2017. Saturn’s moon Atlas, which orbits in the outer edge of the A ring, also has a saucer shape. Pan is not the only moon that might go well with a little marinara. Showalter tells Drake that it’s likely that some of that the fine dust sticks to Pan, and since the ring is much thinner than the moon, it has accrued in an “equatorial accretion disk” or ring around Pan's middle. Pan’s gravity holds open a 200-mile-wide opening in Saturn’s A ring known as the Encke Gap. So why does the little moon have such an unusual, delectable, shape? Stephanie Pappas at LiveScience explains that the moon is known as a “shepherd” because as it orbits Saturn within the planet's iconic rings, its gravity sweeps an area inside the ring free of dusty particles. “It’s very gratifying finally to see Pan’s closeup.” “This is such a far cry from the nondescript ‘dots’ that I was tracking way back in 1990 in the Voyager images!” he tells Drake. While studying the moon may make some researchers a bit peckish, Mark Showalter, a senior research scientist at the SETI Institute who, along with a colleague, originally discovered the moon back in 1990 by examining data from the Voyager 2 mission, finds the images fascinating. Loren Grush at The Verge reports that the staff at the website likened the moon to half an avocado, a belly button, fresh naan bread, Gilligan’s hat, a space pimple and a hamburger tilted to 80 degrees. The moon has been described by astronomers and journalists as a ravioli moon, a space empanada, a walnut, and a pierogi. ![]() As moons go, Pan is downright cute, with an oval-shaped main body surrounded by an equatorial ridge. The most striking thing about Pan is its unusual shape. Its latest find, however, is not nearly so menacing-earlier this week Cassini sent back the best images yet of Saturn’s moon Pan, a tiny 21-mile wide body hiding in the planet's A ring, reports Nadia Drake at National Geographic. NASA’s Cassini spacecraft has been buzzing around Saturn and its many, many moons for the last 13 years, sending back the first close-up images of the geologically active Enceladus, Saturn’s hexagonal storm, and Mimas, a moon that looks like the Death Star. |
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