Iapetus Cracked Like a Nut

first_imgSaturn has a moon named for the two-faced Roman god Janus, but the real two-faced moon is the larger Iapetus.  Since Jean Dominique Cassini discovered the moon in 1671 and noticed its varying brightness, scientists have been mystified by its two hemispheres, one as black as coal, the other white as snow.  Investigators were sure they would figure it out when Voyager 2 flew by in 1981.  They didn’t.  Investigators were hopeful they would figure it out when Cassini flew by less than two weeks ago on December 31, 2004.  They didn’t.  In fact, they were thrown another curve: a ridge that wraps around the equator that gives the moon the appearance of a cracked walnut (see imaging team picture and caption).  This is no ordinary crack; the ridgeline forms a mountain range 800 miles long and 13 miles high in places – three times the height of Mt. Everest.  For a global perspective, see this 3D image and this composite of the dark hemisphere.  The landslide at the right of the previous image slumped from a 9-mile scarp of an impact basin, and flowed tens of miles across a crater floor.    For decades, scientists have tried to prove one of two models for Iapetus’ black-and-white contrast: either the dark material erupted from the inside (endogenic) and spread over the surface, or was splattered onto the moon from the outside (exogenic).  Since the dark material covers the leading hemisphere (the side facing the orbital motion, like a windshield), the exogenic model has been slightly favored, but planetary scientists could not understand a source for the material that would not have also plastered the inner moons, unless it was dust blown off from an impact on Phoebe (see 06/14/2004 headline) – but the spectra didn’t match.  The new hi-resolution images from Cassini, taken seven times closer than Voyager, still favor the exogenic model, because the dark regions have feathery edges and are distributed around the equator, not the poles.  The pictures seem to rule out a liquidy or mushy ooze spreading out from the interior, but scientists cannot eliminate the possibility that dusty debris erupted from cracks or geysers.  Could geological processes related to the equatorial ridge be related to the dark material?  If so, what drove those processes on a frozen moon?    The ridge is a geological feature unique in the solar system.  It seems to cut right through more ancient craters.  The albedo difference divides the leading and trailing hemispheres, but this ridge divides the northern and southern hemispheres.  Are they related?  Since Iapetus is “far out” (literally and figuratively), Cassini won’t get another chance to observe it at close range till 2007.  That encounter, in September of that year, will be much closer and provide 100 times better resolution.  The JPL press release says scientists are hoping to determine whether Iapetus was volcanically active in the past – odd for an icy-cold moon far from any tidal influences.  Two weeks ago, scientists had a major mystery to solve at Iapetus; now they have two.Planetary science is the art of building skeet for observations to shoot down.  Next episode in this exciting sport comes this Friday, when the Huygens Probe parachutes to the surface of Titan.(Visited 10 times, 1 visits today)FacebookTwitterPinterestSave分享0last_img read more

Qantas: Airfares to fall

first_imgQantas boss Alan Joyce expects airfares to keep falling after a decline of almost 40 per cent over the last decade, while the Boeing 787-9 to be delivered next year, will offer passengers new non-stop options.Unveiling a record net profit of more than A$1 billion, Joyce said the airline had kept ahead of declining fares through restructuring which had cut costs by  A$1.66 billion while , improving its service and product offering and taking advantage of  new technology such as the 787.This had allowed it to achieve record results while consumers “have never had it better”, he said.“Airfares are typically 30 to 40 per cent below where they were 10 years ago. The aviation industry is one of the few industries where every year on average, airfares come down.“Consumers are getting the best product at lower airfares and what’s great is that thanks to our transformation program we’re making money and we’ve been able to adapt.’’Joyce pointed to a comparison of fares during the 2000 Olympics where Ansett Airlines had offered airfare specials of $A400 between Melbourne and Sydney.“Qantas fares today [on the same route] averaged $A160 and Jetstar fares were below $A100,” he said. “If you take Hong Kong, back then the Ansett special was $A1800, we typically have a $A900 airfare to Hong Kong,’’ he said. “But we’re doing that profitably.’’On the 787-9 the airline will unveil the interior design in late October and early next year the new routes that the aircraft will fly.Candidates are London-Perth, Dallas-Melbourne and Dallas-Brisbane.Qantas’s low cost subsidiary Jetstar has a fleet of 11 787-8s in service.Initially the Boeing 787-9 will used on Qantas’s regional international and domestic routes for operational experience and tickets for those services will go on sale in December.“Our first flight I still about 15 months away, but I’m delighted to say that Dreamliner flights on our existing network will be on sale before Christmas,’’ Mr Joyce said.“And shortly after that, we’ll be announcing other international destinations that this state-of-the-art aircraft will fly to.’’Joyce said 787 customers could expect luxury suites in business, roomier economy seats with better entertainment options and a revolutionary premium economy product “that is streets ahead of anything else out there’’.Insiders say that the seating configuration will be heavily focused on high yield passengers.last_img read more

Map to help travellers ‘walk in Mandela’s footsteps’

first_imgThe Department of Tourism has launched a travel map to guide and assist people from around the world who may be looking to visit South Africa to “walk in Nelson Mandela’s footsteps”. “To make it as easy as possible for people to personally experience Mandela’s story, we have developed the ‘Madiba-inspired tourist attractions’ map, which encapsulates the key points on his life’s journey,” Tourism Minister Marthinus van Schalkwyk said in March. He was speaking at the launch of the travel map at Drakenstein Correctional Centre (formerly Victor Verster Prison) in Cape Town – the last place where Nelson Mandela was held captive before he took his first steps to freedom on 11 February 1990. Developed by South African Tourism in partnership with the Nelson Mandela Foundation, the map highlights tourist sites as well as general places of interest in the four main provinces that defined Mandela’s life. These include the Eastern Cape, where he was born, grew up and attended Fort Hare University; Gauteng, where he worked as a human rights lawyer and became instrumental in South Africa’s political struggle; KwaZulu-Natal, where he was captured; and the Western Cape, where he was imprisoned and ultimately freed. Since Mandela was released from prison in February 1990, a number of world-class museums, monuments and precincts have been developed to help bring his story to life and to cater for the demand to better understand South Africa’s history. The map includes well-known attractions such as the Unesco world heritage site Robben Island, where Mandela was imprisoned, and Mandela’s house on Vilakazi Street in Soweto, which is the only street in the world to have had two Nobel peace prize winners, Mandela and Desmond Tutu, as residents. It also features some lesser-known attractions, such as the Kliptown open-air museum, also in Soweto, which marks the spot where the Freedom Charter was adopted by the Congress of the People, as well as the Nelson Mandela youth and heritage centre in Mandela’s childhood home, Qunu, where he was laid to rest on 15 December. “Mandela’s integrity and spirit of hope, reconciliation and love have touched the lives of millions of people,” Van Schalkwyk said on Tuesday. “This year, we celebrate 20 years of democracy and freedom, and we look forward to welcoming many tourists from around the world to share the South African story and Mandela’s legacy with us. “Not only was Nelson Mandela an incredible man and leader, but he remains a truly global icon. Since 1994, visitors from all corners of the globe have come to South Africa to seek out the places that shaped his remarkable life. His name alone put South Africa on the map; today, we are returning the favour in a literal sense.” According to the Department of Tourism, International visitors to the country increased from 3.4-million in 1993 – the year before Mandela became South Africa’s first democratically elected president – to 13.5-million in 2012, with close to 9.2-million of those being tourists (people who spent one or more nights here). “The numbers aside, what has perhaps been the greatest legacy for tourism is that Mandela has encouraged people from all corners of the globe to come and experience South Africa for themselves,” Van Schalkwyk said. It was also thanks to Mandela, the minister said, that the world “now knows South Africa for more than just our incredible wildlife, amazing scenic beauty and excellent value for money. Since 1994, the world has come to realise that what really sets this country apart is Mandela’s people, whose warmth and hospitality leave all who visit us touched by the ‘Madiba magic’.” SAinfo reporter View the map online at mandela.southafrica.netlast_img read more

Brandon Monebrake, Nov. 27

first_imgShare Facebook Twitter Google + LinkedIn Pinterest We are completely done. We finished the Friday before Thanksgiving with our crops and we finished up our custom work the day before Thanksgiving. We got done and moved stuff home that Sunday and started with the custom work on Tuesday and everything has dried up since.The last field we were in was wet and we will have to do some tillage where some places are torn up depending on how dry things get. There are people working ground around us right now.We had a little grass in the corn up at New Paris where the water stood and drowned out the corn. That hurt yields some. We had a good bit drowned out with the fields where we did our custom work too.The corn ended up around 190 bushels or 200 and the beans were 64 or 65 bushels overall. We thought corn would be around 165 and the beans would be around 50 and when we got into them we were really surprised. Things ended up really decent.The beans held up well through harvest. We had a big wind that broke the tops out of a lot of the corn right above the ears. It seemed like the harvest was never ending because every time you turned around it was raining.We are going to clean out dryer and work on some end of the year jobs now.last_img read more

GREEN BUILDING TIP: Sell Energy to Your Utility Company

first_imgFrom the BlogsResisting the Allure of Small Wind Turbines Green PointsLEED for Homes Up to 10 points may be earned under EA1 (Energy & Atmosphere) or EA10 for renewable energy systems.NGBS/ICC-700 Energy Efficiency: points awarded based on renewable energy production — 1 pt. per 200 watts (704.3.3.2). Photovoltaic panels and are one of the design cornerstones of zero-energy homes, which produce as much electricity over the course of a year as they consume.Installing enough PV to accomplish this costs tens of thousands of dollars, but as the price of photovoltaic modules continues to fall and efficiencies go up, net-zero performance will be available to many more U.S. homeowners.In addition to incentives and rebates , net metering laws can help ease the cost of producing your own power.These laws require utility companies to buy electricity generated on-site from customers at the full retail rate. Typically the electricity meter runs backward when power is flowing into the grid (such as sunny or windy days), which offsets the amount of electricity you have to buy at other times (at night or when the wind isn’t blowing).—_This GREEN BUILDING TIP is from our Strategy Generator. Build a tip sheet for your green building or remodeling project under the Strategies & Details tab._ Learn more in the Green Building Encyclopedia:PHOTOVOLTAIC (SOLAR) ELECTRICIYWIND-GENERATED ELECTRICITY From the Green Primer Are features like solar panels absolutely necessary?last_img read more

The Airport House: Measuring Results

first_imgVerifying the heat load calculationsAs discussed in a previous article on heating and cooling, the Manual J design heat load for my house is 34,000 Btu/hour at a design temperature of 7°F. To check this, I used a method of calculating the heat load based on fuel use as described in this GBA blog by Dana Dorsett.The heating demand is satisfied by a combination of internal gains and furnace output. The contribution of the furnace is calculated based on historical fuel use data. To calculate the contribution of internal gains, this method relies on a guess at the home’s balance point, which is basically the outdoor temperature at which internal gains would keep the house at the design indoor temperature. A better insulated home will have a lower balance point than a poorly insulated home. Homes with a lot of solar gain or other internal gains would have lower balance points. Dana recommends guessing 60°F for a house with 2×6 walls and 65°F for a house with 2×4 walls.Instead of simply guessing what the balance point was, I attempted to determine the balance point by applying Dana’s method to four different months of fuel use data. For each of the four months, I tried four different levels for balance point, 50°F, 55°F, 60°F, and 65°F. The estimated heat load gets lower as the presumed balance point gets higher. However, the slope is steeper for warmer months. (That is probably why Dana recommends using mid to late winter bills.)The negative slope results from assuming that a lower proportion of the heat comes from internal gains as the balance point increases. (This does not imply that modifying the house to have a higher balance point would reduce the heat load.) I graphed the results (see illustration #3 below). In theory, the lines for the different months should intersect at the actual balance point and design heat load. In practice, noise factors like varying occupant behavior cause some divergence from the theory. Based on the graph, I believe the balance point is in the ballpark of 56°F and the heat load is in the ballpark of 28,000 Btu/h.The lines for October to December seem to cross as expected. However, the line for January appears to have shifted. This could be due to noise factors or could represent an actual change in the heat load. I would expect some drop in the heat load because we improved the insulation in our attic around that time, as mentioned in a post I wrote in GBA’s Q&A forum.In relying on the Manual J calculations, I specified a two-stage furnace with an output rating of 39,000 Btu/h on high stage, against the HVAC contractor’s recommendation. On mornings with single-digit temperatures this winter, however, the furnace ran continuously without satisfying the thermostat setpoint. I have not yet figured out why that happened. Is the heating load actually substantially higher than suggested by the Manual J calculation or the calculation based on fuel usage? Is the furnace not actually putting out its rated output capacity? (I did verify that the fan speed changes as expected when it is supposed to switch from low stage to high stage.)One theory is that the small fan that goes with the small furnace is not able to distribute the heat throughout the relatively large house. I didn’t worry too much because the house never got uncomfortable and the temperature came up to the setpoint rapidly once the sun came out.Another decision that the HVAC contractor pushed back on was my decision not to install a humidifier. On that front, the data say that I was right. The indoor relative humidity did not go below 30% over the course of the winter. We have now been living in the house for about nine months. I would like to wrap up this series of articles by discussing the measured performance. I’ll start with the blower door test.One of our goals during construction of the house was to make it airtight. Of course, no house is ever completely airtight. Some houses leak a little and other houses leak a lot. The standard way of measuring airtightness of houses is a blower door test.A fan is installed into the front door so it blows air out. An equal amount of air comes in through whatever leakage paths are in the house. The technician adjusts the fan speed while measuring the pressure difference between the inside of the house and the outside of the house. That determines the rate of airflow required to establish a 50 pascal pressure difference. The air flow rate is compared to the volume of the house to calculate the number of air changes per hour, called ach50.A low ach50 number is good. We had a blower door test performed on our previous house, which was built in the early 1990s. The ach50 was about 10. That house had many of the symptoms of poor air sealing: rooms that were uncomfortably cold whenever it was windy in the winter, for example. Floor plan complicated air-sealingThe floor plan of our house is not ideal for air sealing. The fact that only some of the house has a second story and the ceiling in the hangar is midway up the second story meant that we had more wall/ceiling intersections to seal. We did a number of things to improve the airtightness.The worst areas in most houses are the ceilings and the rim joist. To reduce air leakage through the ceilings, we:Located the attic accesses either in the garage or in the gable ends to avoid leakage around attic access doors.Avoided recessed can lights.Used spray foam around the intersection of the walls and ceilings.To reduce air leakage around the rim joists, we:Applied a peel-and-stick membrane on the exterior extending from the foundation concrete to the wall sheathing.Used spray foam on the interiorTo reduce air leakage through the walls, we:Taped the joints of the OSB sheathing.Caulked around the framing on the interior sideSelected high-quality casement windows.So, did these things work? Yes, they did. Our blower door test result of 0.82 ach50 proves it. Cooling loadsThe Manual J calculated cooling load for the house was 18,000 Btu/h at 88°F. The smallest central air conditioner that was readily available was a 2-ton (24,000 Btu/h) unit. I haven’t attempted to systematically measure the cooling load. Anecdotally, I notice that the air conditioner runs about half of the time on the few occasions that the outdoor temperature has reached the mid 80s this summer. I wish I would have spent the extra money for a two-stage air conditioner. When only one zone is calling for cooling, it is sometimes uncomfortably cold close to a supply register. If we had a two-stage unit and a zone controller smart enough to use the low stage when only one zone is calling, that problem would be mitigated.Out of curiosity, I installed a remote temperature sensor in the attic while dealing with the insulation issue. On a sunny day, it is not uncommon for the attic air temperature to be 20°F to 25°F warmer than the ambient outdoor air temperature. So, for cooling, the delta T through the ceiling is commonly three times larger than the delta T through the walls.The relative humidity on the first and second floors seems to average about 50% in the summer without supplemental dehumidification. In the basement, the temperature stays in the low 70s without ever calling for air conditioning. The relative humidity in the basement often pushes 60% if I don’t run a dehumidifier. New construction houses now usually have an ach50 of between 3 and 4. To be certified under the very rigorous Passive House standard, a house needs an ach50 of less than 0.6. Builders of Passive Houses go to great lengths to get to that level. For our house, the heating and cooling load calculations assumed an ach50 of 1.5, although I hoped for better. Editor’s note: This is the last in a series of guest blogs by Reid Baldwin about the construction of his house in Linden, Michigan. For a list of previous blog posts on GBA by Reid Baldwin, see the “Related Articles” sidebar below. You can read his entire blog here.center_img BLOGS BY REID BALDWIN Solar and Hot WaterExperiments in Home AutomationChoosing and Installing an ERVHeating and CoolingWalls and Insulation Energy Efficiency and Garage Space for an Airplane RELATED ARTICLES Is Modeling a Four-Letter Word?Energy Modeling Isn’t Very AccurateTackling the Plug Load Problem Why Don’t Green Buildings Live Up to Hype on Energy Efficiency?Saving Energy With Manual J and Manual D Overall impressionsDuring the process of designing, building, and living in this house, I have learned a lot about building science, HVAC, and the housing construction industry. Fortunately, I learned most of it in time to incorporate that knowledge into my house. There are a few things that I learned about too late in the process to apply. I got a much better result in terms of energy use and comfort than I would have gotten if I simply hired the usual cast of professionals to do what they usually do.The cast of professionals that I hired also learned some things. It seems that only a tiny fraction of the industry is actively applying a lot of what experts know about how to build houses. Hopefully, my project made that fraction a little bit less tiny.last_img read more

BlackBerry CEO Thorsten Heins: Maybe Not A Patsy After All

first_imgThe Rise and Rise of Mobile Payment Technology Thorsten Heins was supposed to be the steward that oversaw the final collapse of one of the great technology companies of the last 30 years. When Heins took over Research In Motion in early 2012, not many people gave him a lot of hope. “Thorsten Heins Is A Patsy Set Up To Fail” was my take here on ReadWrite.At the time, Research In Motion (now BlackBerry) was grasping for straws. It had just reported half a billion dollars in quarterly, losses and co-founders and co-CEOs Jim Balsillie and Mike Lazaridis were getting ousted by the RIM board — a panel they ostensibly controlled for more than a decade. At the time, Heins was seen as a front guy while Balsillie and Lazaridis pulled his strings from behind the curtain. Heins was supposed to be Norville Barnes. So long, Mike Lazaridis Heins Comes Into His OwnFast forward to today. BlackBerry has a new name, a new series of good smartphones in its BlackBerry Z10 and coming Q10 devices and a streamlined and more efficient business that has renewed focus on services and applications. In its latest quarterly earnings report, BlackBerry announced $94 million in profit and said it sold a million BlackBerry Z10 devices in a little over a month, with strong channel sales likely to come. “Our financial transformation over the past 12 months has been outstanding,” Heins said on the company’s earnings call. “To say that it was a very challenging environment to deliver improved financial results could well be the understatement of the year. In the face of numerous challenges this past year, BlackBerry has gone from a significant operating loss in the first quarter of the year to an operating profit in the fourth quarter.”Heins, who is prone to over enthusiasm and exaggeration, wasn’t lying. The company swung to profit from a GAAP loss of $518 million and an operating loss of $118 million. In that time, BlackBerry’s liquid cash hoard rose from $2.1 billion to $2.9 billion despite losing market share to the like of Android and Apple.Balsillie is gone. Lazaridis is retiring at the beginning of May. It appears that Heins has taken hold of BlackBerry and made it his without the puppeteers manipulating from the background.Remaking BlackBerry In His Own Image“Thorsten has been doing a good job at the helm, in my opinion. He got the devices to market (although a bit later than expected),” mobile analyst Jack Gold, principal at J. Gold Associates, wrote me in an email. “He’s effectively managing the bottom line (still not done but he’s on his way), and he’s made a number of management changes. The restructuring isn’t totally done yet, but he does seem to be remaking BB in his image of what it needs to be.”Heins & Alicia Keys at BlackBerry 10 LaunchBlackBerry and Heins had a baptism by fire in 2012. The new BlackBerry 10 mobile operating system was delayed. Then it was delayed again. BlackBerry completely missed the holiday shopping season, eventually launching its new devices on Jan. 30. at an event in New York City. Between the time that Heins took over and the launch of BlackBerry 10, the company was forced to lay off thousands of workers. It got so bad that BlackBerry hired powerful Wall Street groups J.P Morgan and RBC Capital to perform a strategic review, something that pointed to a potential sale of the company.Instead of a sale, it seems that the strategic review has led to a leaner, meaner BlackBerry. The company saw a billion dollars in savings from operating income a year before it expected to. That has led to profitability, even though BlackBerry technically lost 3 million subscribers (from 79 million to 76 million) in the most recent quarter. Just The BeginningBlackBerry is not done though. Heins called the profitable quarter and launch of BlackBerry 10 just the beginning. It has yet to launch the BlackBerry Q10, which like BlackBerrys of old features a physical keyboard, though it has been testing the device on 40 carriers in 20 countries. In 2013, more BlackBerry 10 devices will be released at lower price points to take advantage of emerging markets where BlackBerry plays particularly well, like the Middle East and Africa. BlackBerry Z10“Everyone at BlackBerry understands that there is more work to do. Delivering BlackBerry 10 and a profitable quarter is just the starting line, not the finish line,” Heins said.Through it all, Heins comes out looking like a hero. Instead of a patsy, he has superseded both Balsillie and Lazaridis and given the BlackBerry tangible hope for a profitable future. It may only be the beginning, but Heins’s first year of hardship is over. “Of course, the next two-to-four quarters will give us a better understanding of how successful he’s been, but so far I give him a pretty good grade,” Gold said.Lazaridis photo courtesy of Wikipedia  Role of Mobile App Analytics In-App Engagement dan rowinski What it Takes to Build a Highly Secure FinTech …center_img Why IoT Apps are Eating Device Interfaces Tags:#BlackBerry#BlackBerry 10#mobile#Thorsten Heins Related Posts last_img read more