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Latest Evidence that Saturn and Its Rings Are Young

first_imgA new set of post-Cassini papers has to deal with observational facts: Saturn and its rings cannot last billions of years.Science Magazine just added to the growing body of post-Cassini literature analyzing 13 years’ worth of data gathered by the legendary Saturn orbiter. During the last 22 “high-dive” orbits in 2017, Cassini had unprecedented opportunities to sample the space between the rings and the planet. Here are some of the surprising findings being reported.Hsu et al, “In situ collection of dust grains falling from Saturn’s rings into its atmosphere” (Science). A “ring rain” of nanoparticles detected by the Cosmic Dust Analyzer (CDA) puts an upper limit of 400 million years on the rings.Mitchell et al, “Dust grains fall from Saturn’s D-ring into its equatorial upper atmosphere” (Science). Atmospheric drag is ejecting dust from the D-ring analogous to “sawdust ejected from a circular saw as it cuts through wood.” They believe the process “plays a role in slowing the fall of the dust through the atmosphere,” but sawdust does not normally evolve back into wood.Waite et al, “Chemical interactions between Saturn’s atmosphere and its rings” (Science). This paper, with co-author Jeff Cuzzi, a ringmaster most of his professional life, cannot support billion-year rings. Water is falling into the planet from the rings at a rate of up to 45,000 kilograms per second. Other compounds are also flowing off the rings into Saturn, as measured by the Ion and Neutral Mass Spectrometer (INMS). Here’s the team’s conclusion:The large mass of infalling material has implications for ring evolution, likely requiring transfer of material from the C ring to the D ring in a repeatable manner. The infalling material can affect the atmospheric chemistry and the carbon content of Saturn’s ionosphere and atmosphere.Cassini dives through the gap between the D Ring and Saturn during its Grand Finale before burning up in Saturn’s atmosphere on September 15, 2017.Here’s the operative quote about ages: not millions of years, but thousands?The mass of Saturn’s C ring is ~1018 kg, about 0.03 times the mass of Saturn’s moon Mimas. Therefore, if we use the mass influx inferred from the INMS measurements (4800 to 45,000 kg s–1), we calculate a lifetime of 700,000 to 7 million years for the C ring. Yet this only reflects today’s influx. The current influx is directly from the D ring rather than the C ring, which must be the ultimate supplier because the mass of the D ring [likely no more than 1% of the C ring mass] can maintain current loss rates for only 7000 to 66,000 years—a very short amount of time in terms of solar history. It is unclear whether the C ring can lose 1% of its mass into the D ring by viscous spreading over that time period.Although viscous spreading of the C ring is likely not the cause of mass transfer to the D ring, occasional transfer of ~1% of the mass of the C ring into the D ring region via a large ring-tilting event is feasible. These ring-tilting events involve a stream of planet-orbiting rubble crossing the ring plane somewhere in the C or D rings. The C ring provides the ultimate source, containing enough mass to last (at current influx rates) about 5% of the time that the rings themselves have existed (~200 million years). The D ring could be repopulated sporadically by large impact events such as those that tilted the D and C ring plane. Once enough small particles are brought into the D ring region, exospheric drag would quickly drain them into the planet, as observed by Cassini.Notice that keeping the rings old (“repopulated”) requires an appeal to the old-age standby explanation: impacts. The number of lucky impacts needed to keep the rings billions of years old, however, stretches credibility.Perry et al, “Material Flux From the Rings of Saturn Into Its Atmosphere” (Geophysical Research Letters). This team measured the flow of nanometer-sized particles from the rings that are swept up by Saturn’s atmosphere and dragged into the planet. The predicted flux was wrong, and had to be revised upward significantly. It’s “exciting” to be wrong by a factor of a hundred, isn’t it?Surprisingly, the flux is a hundred times larger than past predictions, and at least half of the material is hydrocarbon, which comprises less than 5% of the water ice‐dominated rings. Cassini’s data also show that the influx varies at least a factor of 4 and may be linked to clumps that appeared in 2015 on D68, the ringlet on the inner edge of the rings. These newly discovered particles and processes alter the evolutionary landscape of the rings and provide an exciting, rich field for future research aimed at understanding the origin and history of the rings.How This Came Across in the Popular PressLeah Crane, “Cassini revealed three big surprises before diving into Saturn” (New Scientist). Can Ms Crane bring herself to criticize planetary scientists who got things so wrong? On the subject of Saturn’s magnetic field, she comes close:The magnetic fields of planets in our solar system are all tilted to some extent – Neptune’s is off by a whopping 47 degrees. But Saturn’s magnetic field seems to be perfectly straight, and our current theories of how these fields are generated suggests that should be impossible.“If you don’t have a tilt, you would expect the magnetic field to start dying away, but as we got in really close with the Grand Finale orbits, we saw that it is not,” says Michele Dougherty at Imperial College London.Michele is a dignified and accomplished woman on the Cassini team, but she was wrong on this point. She was wrong on another point, too (as were all the Cassini scientists). Once again, they are excited about being wrong:Even the seemingly empty space between Saturn’s surface and its rings is more exciting than we thought. “There’s this connection between the rings and the upper atmosphere of Saturn that we just didn’t think would be there,” says Dougherty. “That was a complete surprise.”Crane goes on to compare the amount of infalling material (dust, ice and gas), measured to be about 45,000 kg (22,000 pounds) per second, this way:That’s the equivalent of about 1800 cars falling into Saturn every minute – such a downpour may mean that the rings are disappearing faster than we thought.A little math helps picture this. How much material should have been lost in Saturn’s assumed lifetime? 4.5 x 104 kg/s times 86,400 sec/day times 365 days/year times 4.5 x 109 years: if this has been going on for the age of the solar system, Saturn’s rings would have lost 24 x 1021 kg of material by now. In plain English, that’s a whopping 6,500 billion billion kilograms, or 4,800 million billion cars! That’s close to 240 times the entire mass of the rings. Is that credible?Groundbreaking Science Emerges from Ultra-Close Orbits of Saturn (Jet Propulsion Laboratory). Will JPL apologize for getting it so wrong? Don’t count on it. Scientists must always look good to the public, because they are the high priests of knowledge in our culture.Scientists can’t be blamed for things that could not be measured or detected before, obviously, but much of what was taught about Saturn and its rings for decades has just been tossed out the window. The press release mentions “surprise” four times. How about that magnetic field? Haven’t students of geophysics been taught that a dynamo in the core generates the field? That’s been falsified, at least in the case of Saturn; “That might mean that Saturn produces its magnetic field differently from the other planets in our solar system,” Crane said. Actually, it might mean that the theory for generating magnetic fields is wrong for all planets. Philosophers of science look askance at special pleading.That’s not the only mystery or surprise, either. The whole mission was a string of surprises:According to everything scientists know about how planetary magnetic fields are generated, Saturn should not have one. It’s a mystery that physicists will be working to solve….But scientists were surprised to see that others [particles] are dragged quickly into Saturn at the equator. And it’s all falling out of the rings faster than scientists thought — as much as 22,000 pounds (10,000 kilograms) of material per second.Scientists were surprised to see what the material looks like in the gap between the rings and Saturn’s atmosphere. They knew that the particles throughout the rings ranged from large to small. But the sampling in the gap showed mostly tiny, nanometer-sized particles, like smoke, suggesting that some yet-unknown process is grinding up particles….Indeed, says project scientist Linda Spilker, “Almost everything going on in that region turned out to be a surprise.” No shame, though; “the data is tremendously exciting.”Now what? “Many mysteries remain, as we put together pieces of the puzzle,” Spilker said. “Results from Cassini’s final orbits turned out to be more interesting than we could have imagined.”In all these surprises, mysteries, and falsifications, one thing is never called into question by secular planetary scientists: the assumed age of the solar system. That figure—the Law of the Misdeeds and Perversions—cannot be altered.Instead of hiding their heads in shame, they are excited about being way off. So what is the likely impact of the revised estimates? Saturn’s rings are young. Plug that into your story of “understanding the origin and history of the rings.” The ramifications are likely to ripple across the solar system, all the way to Earth. (Visited 575 times, 1 visits today)FacebookTwitterPinterestSave分享0last_img read more

Chesa Nyama to open restaurant in the US

first_img26 February 2016Chesa Nyama is going to America, but what exactly is chesa nyama, or shisa nyama?According to South Africa braai connoisseur Jan Braai, while “chesa nyama” might literally mean “to burn meat” in isiZulu, it is a lot more than that. It is an informal social event involving the traditional meat braai, where friends and even strangers gather to celebrate the great South Africa social culture of food and community. It is an opportunity to bring together people of all walks of life with good food and good music, to make great memories.Chesa Nyama heads to the US https://t.co/DwN95z0tN6 pic.twitter.com/Q4imsTmXgc— Eyewitness News (@ewnupdates) February 24, 2016Chesa Nyama is one of South Africa’s fastest growing national brands, a traditional braai restaurant franchise hugely popular with young people and people looking for an authentic taste of African braai cuisine.It has almost 300 franchises across South Africa and employs over 3 000 people. The brand’s rapid growth led to the listing of its owner company, Gold Brands, on the JSE at the beginning of 2016.Congratulations to our holding company Gold Brands for being the only fast food company to be listed on the JSE! pic.twitter.com/z5GLd5bcVr— Chesanyama (@Chesanyama_SA) February 19, 2016Gold Brands is now set to export the success of Chesa Nyama and South African braai culture to the United States, with plans to open its first restaurant in Nashville, Tennessee in October.Gold Brands announced on 23 February that the company had signed a memorandum of understanding for the expansion of the brand with private investors, the South African industrial holdings firm Red Hornbill, and the White Family Partnership, an American partner.#SouthAfrican born brands can achieve success. 3 year old #ChesaNyama franchise chain announced it opens in US this year #WednesdayWisdom— Commstrategis (@Commstrategis) February 24, 2016An area development agreement between these partners allows for the establishment of Chesa Nyama Holdings in the US, with Gold Brands as a partner in the joint venture. It will own 30% of the American company and Red Hornbill will own 40%; the remaining 30% percent will be held by the White Family Partnership.According to the deal, Red Hornbill and the White Family will cover the funding of the Nashville set up as well as establishment costs for the further roll out of the franchise in the US. While Gold Brands will not provide capital for the US venture, it will be responsible for logistical support in the development of the product lines, branding, menu costing and strategic support.Gold Brands’ chief executive, Stelio Nathanael, explained the origins of the expansion plans to CNBC Africa: “We have long had a dream of taking Chesa Nyama beyond the borders of Africa. The idea has always been to bring our iconic South African braai culture to America.”We can not blame the Americans for loving #Chesanyama! No one can resist the #Nyamalicious treats! #ProudlySA pic.twitter.com/dpj5MxEK2c— Chesanyama (@Chesanyama_SA) February 24, 2016“(While) we’ll have to teach (the Americans) how to say Chesa Nyama first,” Nathanael joked, “it’s more about a restaurant dining concept giving that African feel and what we as South Africans are about.”He attributes the success of the brand to South Africans who embrace the combination of tradition with the contemporary. “(Our customers) love the brand so much, love the vibe of the brand. (but) they (also) love the tradition of Chesa Nyama and bringing it from the township to the suburbs is the reason for its success.”He is confident the model will translate not only to a large African expatriate community in Nashville, but also to Americans looking to try something a little different.Source: ENCAlast_img read more

Weekend Project: Make Your Own NFC Tags

first_imgRelated Posts sarah perez Tags:#How To#mobile#web As noted above, we’re focusing on making tags using your Android phone. There are actually several apps that allow for this now in the Android Market. One such app, to give you an idea, is the NFC Task Launcher from developer Joshua Krohn. We were introduced to this app via an NFC World interview.In detailing the potential uses for NFC tags, Krohn told the website:You could have a tag that enables Wi-Fi, configures your wireless network and then connects — so visitors would never have to enter your security key to use your wireless connection. They would not need to have an open network, they would only need to scan the tag and the rest is done for them.He personally uses NFC tags in his car, his home and his workplace, where he uses them to put the phone into different modes. For example, in the car, a tag enables Bluetooth, disables Wi-Fi, sets the media volume to max and launches the Car Home application. And all with just a tap!Meanwhile, at the office, another tag enables Wi-Fi, disables Bluetooth and connects to his work’s secure network.Currently, his NFC Action Launcher application supports these tasks:Enable / Disable / Toggle WifiEnable / Disable / Toggle BluetoothLaunch any installed ApplicationConnect to any known SSIDConfigure a new Wifi Connection and connectConfigure and enable Portable HotspotEnable / Disable Auto-syncLaunch any Tasker Task (for users of Tasker)Changing Phone RingtoneChange Notification ToneChanging Ringer Mode (Normal/Silent/Vibrate)Changing Ringer VolumeChanging Media VolumeChanging Alarm VolumeChanging Notification VolumeYou can also use it to create task tags, profile tasks, vCard tasks, Smart URL tags, text tags and URI tags (Tel, SMS, Mailto). Originally launched on the XDA Developer forums, the app is now availalbe in the Android Market here for $1.99.Similar apps in the Market include Touchtag’s client (free), NXP’s TagWriter (free), taglet (free), Write a Tag (free), AnyTag (free), NFC Classic Tag Reader Writer (free) and others, mostly in Japanese.For experimental purposes though, it’s nice when the developer is hanging around in the forums, responding to user questions, like Krohn does here. That may be worth the $2 to you when choosing what app to try.To see what tag reading and writing looks like in action, check out this YouTube video. Why IoT Apps are Eating Device Interfaces Role of Mobile App Analytics In-App Engagementcenter_img NFC, or near field communication, is an emerging technology that will power mobile payment systems and mobile wallet solutions, like those in development by Apple, Google, RIM, mobile operators, banks and others. But NFC itself is just a way to send data wirelessly between devices, meaning it can be used for far more than mobile payments alone.One way to take advantage of a phone’s NFC capabilities is to make your own NFC tags. These tags, when read by your phone, can perform a number of actions, like open a map, launch a website, change your phone’s settings and configurations, plus dozens of other tasks. Wouldn’t it be fun to make tags like that? Well, now you can. Here’s how.One of the most popular phones to have NFC built in is Google’s flagship device, the Samsung Nexus S. However, it’s not the only one. There are many phones you can buy today that have NFC built in, and there are several more than are coming soon, like the Nokia Astound (C7) or Samsung’s Galaxy S II, which will include NFC in some models. You can check out a more complete list of NFC phones here for details.But for our purposes, this project will focus on using Android phones, specifically the Nexus S.Where To Get NFC Tags Of course, before you can make your own NFC tags, you first have to acquire them. These aren’t available on the shelves at Best Buy, so you’ll have to order them online. Thanks to software developer Joshua Krohn, who made the NFC Task Launcher app described below, we have a good list of sites selling NFC tags.These include the following:Tagage: This Finland-based store ships NFC stickers worldwide to many countries, including Australia, Austria, Belgium, Bulgaria, Canada, Chile, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hong Kong, Hungary, Ireland, Italy, Japan, Latvia, Lithuania, Luxembourg, Malaysia, Malta, Mexico, Netherlands, New Zealand, Norway, Philippines, Poland, Portugal, Romania, Saudi Arabia, Singapore, Slovakia, Slovenia, South Africa, Spain, Sweden, Switzerland, Taiwan, Thailand, United Arab Emirates, United Kingdom, United States. U.S. shipments take about 5-7 days. Sparkfun: For U.S. customers, Sparkfun sells laminated U.S. tags.Touchtag: Also U.S.-only, Touchtag sells various starter kits of 25 or 500 tags.CoreRFID: In Europe, this U.K.-based RFID shop sells different types of tags, like these sticker discs and more. BuySmartCard: Serving the Asian market, this store sells tags that ship from Hong Kong. (Details from XDA Developers forum here.)Write Tags with NFC Task Launcher for Android What it Takes to Build a Highly Secure FinTech … The Rise and Rise of Mobile Payment Technologylast_img read more

Exclusive interview: India out-bowling England, says Graeme Swann

first_imgShadows of the 2011 whitewash are quickly vanishing as India puts up a much more spirited performance against England this time around in 2014. It’s been a compelling series, one where India have had their noses ahead, drawing at Trentbridge and now with looking to make a bigger impact at Lord’s. England is no longer the force it was in 2011. So is this India’s best chance to win in England and exorcise the dark ghosts of 2011. Recently retired English spinner Graeme Swann feels it’s all about the pitches.In an exclusive conversation with Shivani Gupta, Swann said, “It is perhaps India’s best chance to win in England. That’s perhaps a very astute comment. India is out-bowling England, putting balls in the right places.””Pitches are not supporting England. They don’t play the same as they used to, not the same as the ones that James Anderson and Stuart Broad thrive on. But India is missing a trick by not playing Ashwin. With two spinners in the second innings they could be better off.”The English itself are facing the heat, not having a won a Test in their last nine matches, equaling a win-less run from more than two decades ago. Can this team beat India?”Team is in transition. Lots of names not there anymore – Pietersen, Trott and me. If the wickets were similar to 2011, England  would win because of their superior seam bowling. But this is where the problem is. Such is the lack of traditional English wickets, that when they do get it like the first day at Lord’s, bowlers were so eager to cash in that they bowled poorly. India out-bowled us. Bhuvneshwar Kumar was exceptional. It’s strange that India did better in conditions tailor-made for England. The team in 2011 could beat this India team, of course because I was in it,” he adds with a laugh. advertisement”I won’t say the England team is unraveling now, it has already unraveled since Australia. It’s a team with a new coach, the captain is in a beleaguered position. Lots of people are questioning him. He needs to forget about it and concentrate on scoring runs and everything else will take care of itself.””I know Alastair Cook very well. He’s a very stubborn individual, he won’t be listening, but the more people bang the drum, the louder the noise. Especially the England press is very much like the Indian press. When India doesn’t do well, they go after Dhoni, same here with Cook.’So the big question is – what is wrong with the pitches? Why is England not being able to take advantage of home conditions? Clearly, its not just about being ‘good hosts’ or groundsmen having their own minds.Swann says he has just the answer.”I’ll tell you exactly what’s happening. All the drainage systems put into Test venues over the last few years have sucked all the moisture out. I’ve  been saying this for 2-3 years – at every ground, wickets are getting drier and drier. The Oval is very dry now, spins square there.””Everyone said last year that groundsmen were doctoring wickets to suit me during Ashes, which is flattering?, but really it’s become difficult to keep moisture in the ground. It’s like pouring a glass of water on a sandpit.””I feel for Trentbridge’s pitch marked poor for last week. The groundsmen are actually battling against the grounds at the minute. They are scratching their heads. This wicket at Lord’s too started wet but it’s bone dry now.”Finally, Swann says he has been most impressed with the young Indian batting lineup.”Rahane’s century in the first innings was one of the best I’ve seen in a long time. He must have seen the wicket on the first day and felt like he’s batting on moon, it must have been so alien.””I want to see Virat Kohli bat well. He’s one of my favorite batsmen to watch, not bowl against, and he hasn’t fired yet. And Shikhar Dhawan as well who is a wonderful player. Two guys I thought will be the lynch pins of Indian batting are not contributing yet India is scoring good runs.”Shivani GuptaFollow @shivanigupta_5last_img read more

BW Green Carriers Takes World Fuel Services to Court

first_imgzoomImage Courtesy: BW LPG Norway’s gas transportation company BW Green Carriers AS, part of BW Group, is taking Miami-based bunker supplier World Fuel Services Inc to court over contaminated bunkers.The company filed a complaint at Florida Southern District Court on October 19, 2018, seeking compensation for damages caused by contaminated bunkers to two of its LPG tankers, M/V BW Kyoto and M/V BW Leo, court documents show.The fuel tanked into the company’s ships in April in the Nederland port in Texas has reportedly caused the ships’ fuel pump systems to clog up, posing a danger to the ships’ engines. The fuel had to be removed before causing any further damage.Both BW Group and World Fuel Services are yet to provide World Maritime News with a comment on the matter.Back in September, Trafigura Maritime lodged a complaint against WFSC with Florida Southern District Court over bunker issues.Contaminated marine fuels are believed to have caused operational issues to over 150 ships this year.The contaminated fuels were initially delivered to ships in Houston in January this year, followed by Panama, Singapore and Malaysia in April, causing a myriad of technical and mechanical problems for ship owners and operators.The contaminated fuel can lead to engine failures and associated losses of propulsion, placing the safety of the affected ship and crew at risk.Shipowners’ associations have vehemently criticized lack of action from maritime authorities to address the issue, curb the further spread of contaminated fuels and investigate the causes of the problem and sources of contamination.World Maritime News Stafflast_img read more

Indias synonymy with tea

first_imgIndia has been dancing to the beat of “Cha-Cha-Cha” with every cup of tea consumed and every soul comforted by the taste of brewed magic, be it regular or masala. History suggests tea-drinking commenced around 750 BC, but the origin of tea in India, in terms of commercialisation, goes back to the pre-Independence years, when the British initiated tea cultivation and consumption in the country to challenge the Chinese monopoly in the tea industry. Also Read – Add new books to your shelfWhat began as a business goal soon became a household habit, with almost everyone orchestrating their days to the tune of their tea-cups. After Assam and Darjeeling proved to be successful spots for cultivation, mountainous areas like Kumaon, Dehradun and the Nilgiris were inspired to also do so. The impactful response made India initiate trade and exports to other countries, hence spreading the magic of Indian tea across the globe. The import-export business began to put India on the map for being synonymous with tea and if one has to gauge its resonance, even today, the first beverage that foreigners drink when they come to our country isn’t their regular beer or whisky, it is tea. Also Read – Over 2 hours screen time daily will make your kids impulsiveThat itself speaks a lot about the synonymy of India with chai. Early advertising of tea positioned it as an accompaniment for snacks, be it for the family or for guests. In an attempt to bridge a consumer need and turn it into a profitable venture, tea stalls started popping up around offices for those who couldn’t go home to have their daily dose of chai. High-tea sessions gained momentum, wherein people would gather at each other’s homes and socialise with cups of tea and biscuits or cakes. In fact, it still a tradition in a lot of Indian societies. A basic cup of tea has undergone major changes across the years. From regular and masala, to elaichi, ginger, lemon and more – one thing has, however, remained the same: People like to play around and get innovative with their steaming cups of invigorating chai. Today, tea consumption is at its highest with newer variants being introduced for the health-conscious generation. Green Tea, Herbal Tea and Chamomile Tea are three of the most consumed beverages by Indians because of the magic that they do for one’s immune system. Right from weight control to being rich in antioxidants, the benefits are endless, which makes tea extremely appealing to the current mindset of consumers. It is quite interesting to note how trends dictate the evolution of any industry, for that matter. Looking at the current course of the tea industry, with innovation being the key criteria, there are quite a few interesting trends to look out for in 2019: 4Veggie Tea Mixes: Given the rise of vegetarianism and veganism across the globe, a lot of people want their teas to have vegetables in the composition, some of which include onions, tomatoes, potatoes and more. 4Power Teas: Although several teas provide energy naturally, power teas combining vitamins and herbs is a new trend to look out for, considering the “quick-fix” patterns of people due to the fast pace of life. 4Probiotic Teas: Probiotic teas are those which go through microbial fermentation, which is said to work wonders for one’s immune system as well as improve digestion and help with weight management. 4Natural Colors and Hues: With advent of ‘Instagram-worthy’ pictures, natural colors will play an important part in terms of tea representation for consumers. On International Tea Day, it’s interesting to note how tea has changed over the years, with further innovations to come.last_img read more