Planet Habitable Zone Cannot Be Too Windy

first_imgThe “habitable zone” of a planet usually concerns its distance from the star such that it can support liquid water.  But what if the star fries the surface with intense stellar winds?“Deadly stellar winds could put a stop to life” reads the headline of an article on Astrobiology Magazine.  Planet Earth has a protective magnetic field that shields its inhabitants from the solar wind.  But the solar wind emitted by our star is mild compared to the intense storms of charged particles flung out by other stars.Joe Llama from the University of St. Andrews looked at the winds that bombard one of the “hot Jupiters” (giant planets orbiting close to parent stars), named HD 189733.  He considered what such a wind would do to an earth-like planet, even if it orbited in its habitable zone:In the case of HD 189733b, this is not a huge problem as it and other hot Jupiters are already far too hostile for life to survive. But strong stellar winds could also strip away the atmospheres of potentially habitable planets further out, something that would have dire consequences for their habitability.  Joe comments: “Imagine what the Earth would be like with its air stripped away, placed in a radiation bath. There could be numerous planets like this that in many ways resemble our world, but where life never stood a chance.”The article did not quantify how many stars would irradiate their planets to death, but Llama thinks they “could be numerous”.  There would be no point looking for life on planets in such systems.  “For more than two decades we have been stepping up the search for other planets like the Earth,” he said.  “Our new work will help refine this quest, enabling us to rule out the sites where dangerous activity on stars would kill off life from the start.”Earlier this month on Astrobiology Magazine, Sara Seager of MIT presented a “revised” Drake Equation that leaves off Frank Drake’s final factors about intelligent life evolving.  She’s just interested in any kind of life emerging on a habitable planet.  Llama’s conclusions will surely affect one factor she calls FQ, the fraction of stars that are quiet.  “Some stars are like our solar maximum all the time, with flares and other activity,” Seager said. “We don’t like those noisy stars.”The “habitable zone” theory is is a classic case of dogmatic slumbers being jolted awake by physical reality.  In Carl Sagan’s Cosmos days, it seemed so simple: billions upon billions of stars might have life, based on the idea that all you needed was a rocky planet at the right distance from its star.  Over the past decade we have been adding complications to the “habitable zone” idea, narrowing down substantially the probability of finding those lucky stars.  Last year about this time, our list of factors (reported from astrobiology literature) was at nine (see 9/08/12); we predicted additional factors would be thought of.  Now we have #10: the Stellar Wind Habitable Zone.  Earth continues to look mighty special in this vast universe.  You can thank your lucky stars if your world view requires heavy doses of superstition.  Others of us find positive evidence for intelligent design. (Visited 33 times, 1 visits today)FacebookTwitterPinterestSave分享0last_img read more

admin

New solutions for water conservation

first_imgSouth Africa is pressed to conserve its drinking water. (Image: Clever Green) Pupils in a Pretoria school using water. (Image: Bongani Nkosi) MEDIA CONTACTS • Sputnik Ratau   Spokesperson   Department of Water Affairs   +27 12 336 6813 or +27 82 874 2942  RELATED ARTICLES • Courts to protect South Africa’s water • Absa Campus generates its own power • R500m water deal for rural SA • Better water supply for SA schoolsBongani NkosiIt has become a “moral imperative” for major businesses operating in South Africa to adopt water saving schemes for their buildings, thereby helping the country sustain the declining resource.CEO of car rental company Avis, Wayne Duvenage, did not mince his words at the Sustainable Water Resource Conference and Exhibition. The event, held in Kempton Park on 16 and 17 August, was attended by leading water experts and businesspeople and supported by the International Marketing Council of South Africa – among a range of sponsors.Recycling water for reuse in buildings was the experts’ principal recommendation. Homeowners are also advised to go for recycling technologies.Avis saved 75-million litres of water in 2010 in its major centres in Johannesburg, Cape Town and Durban.The Avis scheme kicked off in 2008 with a R1.9-million (US$264 000) investment, and started paying off in 2009 when the company saved 4.2-million litres.Avis has pumped an additional R1.5-million ($208 000) into the construction of underground water filtration and recycling facilities at its three main depots. The aim is to save at least 95-million litres of water each year.“We decided to recycle water because that was the right thing to do,” said Duvenage. “We’re recycling water that was going down the drain.”The company reprocesses grey water from washing machines and baths, which is then used to wash most of its fleet of 20 000 rental cars, while potable water from public sources remains available to employees for hygienic use.Harvesting rainwater is a focus of Avis’ recycling efforts. “You know how much it rains in Cape Town, so it’s nice to switch off municipal water and use rainwater,” said Duvenage.It’s always recommended for entities to study the impact of their business on the environment, he pointed out.Conserving a precious resourceSouth Africa is water-stressed, experts at the conference revealed. Reports have pointed out that the country runs the risk of facing critical shortages by 2020.“South Africa is stressed both in the quantity and quantity of water that we have,” Duvenage said.Alison Groves, a sustainability consultant at WSP Green by Design, said: “In South Africa we need to get beyond the idea that water is always going to be available.”New solutions are needed to sustain potable water availability, Groves added.Her consultancy group has established itself as an industry leader in the greening of major buildings, having helped big companies such as Absa, Nedbank and Woolworths introduce water-saving and eco-friendly schemes in their properties.Banking group Absa’s headquarters in downtown Johannesburg have been fitted with recycling and rainwater harvesting technology that allows it to save at least 43 000 litres of water every day.Retailer Woolworths’ distribution centre in Midrand, north of Johannesburg, is another facility with a large grey water reclamation system. Groves pointed out that the centre has “irrigation ensured for 10 months per year without using potable water”.Woolworths saves R1-million ($139 000) in municipal water bills per year thanks to its recycling efforts.Other companies, such as South African Breweries, are rolling out major water-saving schemes in a bid to help protect the precious resource.Duvenage pointed out that “business is starting to change its behaviour” in accordance with the green revolution, but there is room for improvement. “We believe business has to act much faster,” he said.Residences can reduce consumptionIt’s not only businesses and public entities that should assume the responsibility of saving water, but homeowners can play a major role as well.The grey water technology of Cape Town-based Water Rhapsody, a specialist water conservation company, has proven its efficiency in recent years.Its founder Jeremy Westgarth-Taylor said that water recycled and harvested through its system is suitable for irrigation, toilet flushing, cleaning and washing.Homes can reduce consumption from 280 litres to “as little as 100 litres per day” and save up to 90% of their municipal water bill by using the system.“But it’s done in such a way that you don’t change your lifestyle. You just take control of your own supply,” said Westgarth-Taylor.Water Rhapsody won the WWF Green Trust award in 1998 for product innovation. It’s helped the University of Cape Town reduce potable water consumption by over 90%.The late Kader Asmal, former Minister of Water Affairs and Forestry, told Water Rhapsody, in a 2010 letter to the company, that its water recycling system helped nourish grass and shrubs in the garden of his Cape Town home.last_img read more

admin

The Obama Time Capsule and the Future of Publishing

first_imgJust when you thought the Obama lovefest was dwindling, Photographer Rick Smolan released his latest book, The Obama Time Capsule. The book includes photography, maps and election results from President Obama’s road to the White House. What makes this project unique is that Smolan offers readers a chance to upload their own photographs and personalize their copies. Said Smolan,”Half the people in the room picked up their cameras and took a photo of the television set just as Obama won.” With The Obama Time Capsule, pictures taken by friends and family will live alongside professional pictures of the campaign trail. Smolan is waiving any profit on the project in the hopes that he’ll provide readers with an affordable product they will cherish with their grandchildren. This user-generated component to the book ensures that The Obama Time Capsule becomes a time capsule for anyone willing to pay the $34.95 to Amazon. Tags:#Book Reviews#web 9 Books That Make Perfect Gifts for Industry Ex… dana oshiro 4 Keys to a Kid-Safe App Related Posts 5 Outdoor Activities for Beating Office Burnout Said Hewlett-Packard’s Andrew Bolwell in a recent ABC World News feature on the book,”We think a book like this that’s printed only after it’s ordered, that’s personalized for the end user, is absolutely the future of publishing. You can have your own family cookbook with Grandma’s recipe through to Martha Stewart’s recipe.” It appears that unbeknown to Bolwell, the future (much like President Obama) has already arrived. RWW has already covered a number of companies where products are produced on an individual basis and personalized to the user. Below is a list of companies that allow users to upload, price and purchase their personalized books: 1. Blurb: Blurb offers users the chance to personalize books in a variety of formats. The quality of this product is extremely striking and buyers can opt for a number of page layouts and finishes. The company is one of the few businesses able to earn healthy revenue in our down economy.2. Lulu: Similar to Blurb, Lulu also allows customers to personalize and create books. Users can upload photos from their Facebook, Flickr and Photobucket accounts as well as directly from their computers. The finished products are sold in the Lulu online storefront as eBooks or physical hard covers. The company even offers square, compact and wallet sized options.3. CreateSpace: In late 2007, Amazon launched CreateSpace as an on-demand book publishing service. In addition to being able to create a personalized book and sell it in the Amazon storefront, users can also create Kindle-specific books, audio CDs, MP3s, DVD’s and video downloads. While the service isn’t as sleek as Lulu or Blurb, the potential to reach the Amazon audience is a huge draw to those looking to earn money with their creative talents. 4. Scribd: Another site with a large audience, Scribd recently launched their own store this past April. With 60 million unique visitors per month, the company is a great platform for those looking to publish their original works. Budding authors can price and publish their books alongside Simon and Schuster titles in the Scribd storefront. For now, the storefront only services the eBook audience. 5. Tastebook: Both Grandma and Martha Stewart’s recipes can live side-by-side in this personalized cookbook making site. Featured in a RWW article on recipe resources, this tool offers users the chance to personalize cookbooks and produce them on an individual basis. The Obama Time Capsule is obviously a very cool project, but it’s clear to see that personalized book production is certainly not a new concept. That being said, regardless of whether or not it’s a paradigm shifter for publishing, the quality of The Obama Time Capsule, coupled with Smolan’s recognition as a TIME photographer and TED speaker will likely still draw fans. UPDATE: It turns out Obama’s Time Capsule IS actually made possible by Blurb’s global print partner network, a partnership which exclusively uses the HP Indigo digital printing presses. Other partners include Google, Facebook, AOL, Glam Media and paper manufacturer NewPage. 12 Unique Gifts for the Hard-to-Shop-for People…last_img read more

admin

3 Jharkhand firms under ED scanner

last_img

admin