Venus Express has charted the first map of the planet's southern hemisphere at infrared wavelengths, which hints that Venus may once have been more Earth-like, with both, a plate tectonics system and an ocean of water. The map comprises over a thousand individual images, recorded between May 2006 and December 2007. Because Venus is covered in clouds, normal cameras cannot see the surface, but Venus Express used a particular infrared wavelength that can see through them. Although radar systems have been used in the past to provide high-resolution maps of Venus's surface, Venus Express is the first orbiting spacecraft to produce a map that hints at the chemical composition of the rocks. The new data is consistent with suspicions that the highland plateaus of Venus are ancient continents, once surrounded by ocean and produced by past volcanic activity. "This is not proof, but it is consistent. All we can really say at the moment is that the plateau rocks look different from elsewhere," said Nils Muller at the Joint Planetary Interior Physics Research Group of the University Munster and DLR Berlin, who headed the mapping efforts. The rocks look different because of the amount of infrared light they radiate into space, similar to the way a brick wall heats up during the day and gives off its heat at night. Besides, different surfaces radiate different amounts of heat at infrared wavelengths due to a material characteristic known as emissivity, which varies in different materials. The Visible and Infrared Thermal Imaging Spectrometer (VIRTIS) instrument captured this infrared radiation during Venus's night-time orbits around the planet's southern hemisphere. The new map shows that the rocks on the Phoebe and Alpha Regio plateaus are lighter in colour and look old compared to the majority of the planet. On Earth, such light-coloured rocks are usually granite and form continents. Granite is formed when ancient rocks, made of basalt, are driven down into the planet by shifting continents, a process known as plate tectonics. The water combines with the basalt to form granite and the mixture is reborn through volcanic eruptions. "If there is granite on Venus, there must have been an ocean and plate tectonics in the past," said Muller. The new map gives astronomers another tool in their quest to understand why Venus is so similar in size to Earth and yet has evolved so differently.
Friday, July 31, 2009
Satellite provides its first visible full disk image of Earth
The latest Geostationary Operational Environmental Satellite, GOES-14, provided its first visible full disk image of Earth on July 27. The prime instrument on GOES, called the Imager, is taking images of Earth with a 1 kilometer (km) or 0.62 mile resolution from an altitude of 36,000 km (22,240 miles) above Earth's surface, equivalent to taking a picture of a dime from a distance of seven football fields. "The first GOES-14 visible full disk image shows little activity in the Atlantic Ocean and two tropical waves located in the East Pacific Ocean with a low probability of becoming a tropical cyclone," said Thomas Renkevens, a User Services Coordinator from the National Oceanic and Atmospheric Administration's (NOAA) National Environmental Satellite, Data and Information Service, Camp Springs, Maryland. "Numerous thunderstorms are seen scattered along the east coast and western Atlantic Ocean, with more significant rains and thunderstorms in the southeast Oklahoma and northeast Texas area," he added. "NOAA will continue to follow the tropical waves and thunderstorms for possible further development, he further added. The GOES satellite system aids forecasters in locating severe weather events and is instrumental in providing early warnings for residents located in the surrounding areas. "Being able to predict the path of a hurricane with reasonable certainty and only evacuating the areas at risk saves communities roughly a million dollars per mile," said Renkevens. "This GOES-14 image also shows a mostly cloud-free southwest United States, with a blanket of low clouds along over the Pacific Ocean off the west coast," he added.. "Capturing this first sharp image is a major milestone for our GOES team. It represents a culmination of this team's hard work and dedication. We still have more to do but full mission success is clearly in our sights," stated Andre' Dress, the NASA GOES N Series Deputy Project Manager, at NASA Goddard Space Flight Center, Greenbelt, Maryland. Launched as GOES-O on June 27, 2009, the satellite was renamed GOES-14 after reaching geostationary orbit on July 8, 2009. The satellite is now approximately 22,300 miles above Earth's surface located at 89.5 west longitude where it will remain during the 5 month checkout period.
120,000 yr old frozen microbe in Greenland may hold clues to alien life
A team of scientists has found a tiny frozen microbe trapped more than three kilometres under glacial ice in Greenland for over 120,000 years, which may hold clues as to what life forms might exist on other planets. The novel microbe was found by Dr Jennifer Loveland-Curtze and a team of scientists from Pennsylvania State University, US. The team coaxed the dormant microbe back to life; first incubating their samples at 2 degree Celsius for seven months and then at 5 degree C for a further four and a half months, after which colonies of very small purple-brown bacteria were seen. H. glaciei is small even by bacterial standards. It is 10 to 50 times smaller than E. coli. Its small size probably helped it to survive in the liquid veins among ice crystals and the thin liquid film on their surfaces. Small cell size is considered to be advantageous for more efficient nutrient uptake, protection against predators and occupation of micro-niches and it has been shown that ultramicrobacteria are dominant in many soil and marine environments. Most life on our planet has always consisted of microorganisms, so it is reasonable to consider that this might be true on other planets as well. Studying microorganisms living under extreme conditions on Earth may provide insight into what sorts of life forms could survive elsewhere in the solar system. "These extremely cold environments are the best analogues of possible extraterrestrial habitats", said Dr Loveland-Curtze. "The exceptionally low temperatures can preserve cells and nucleic acids for even millions of years. H. glaciei is one of just a handful of officially described ultra-small species and the only one so far from the Greenland ice sheet," she added. "Studying these bacteria can provide insights into how cells can survive and even grow under extremely harsh conditions, such as temperatures down to -56 degree C, little oxygen, low nutrients, high pressure and limited space," she explained.
Wednesday, July 29, 2009
Only three operators can offer 3G services in Delhi
Only three telecom operators can roll out third generation (3G) services in Delhi due to a spectrum crunch, Communications and IT Minister A. Raja said Monday. 'Delhi has only 15 Mhz of spectrum available making it possible only for three telecom operators to offer such services,' Raja told Lok Sabha in a written reply. The minister also told parliament that an Empowered Group of Ministers (EGoM) had been constituted to look into matters concerning 3G spectrum auctions, scheduled to happen this year. Each telecom operator (successful bidder) will be allocated 5 MHz of 3G spectrum once the auctions are over. In Delhi, only two private players will be able to offer this high-end services as one slot is already reserved for the state-run telecom operator Mahanagar Telephone Nigam Ltd (MTNL). The minister said West Bengal will get only 10 MHz of spectrum, while Gujarat will have 15 MHz. Such a crunch may lead operators to make crazy bids to acquire spectrum in maximum number of telecom circles, industry officials worry. The government is expected to earn about Rs.35,000 crore from the 3G auctions.
Cyber criminals may have created first 'zombie' cellphone network
Experts have warned that hackers may have created a network of "zombie" cellphones, similar to a network of virus-infected personal computers, to send spam or carry out cyber attacks. 'Botnets' is the term that computer scientists use for such networks of computers. While millons of machines worldwide are said to be secretly running botnet software, no has ever been discovered running on mobile devices to date. However, security firm Symantec, headquartered in Cupertino, California, warns that a piece of software known as Sexy Space may be the first case. The firm has revealed that the software uses text messages reading "A very sexy girl, Try it now!" to jump between phones. Symantec experts say that the message contains a link that, upon being clicked, asks the user to download a software program. Just in case the user installs the software, it sends the same message to contacts stored in his/her cellphone. Although similar SMS viruses have been seen before, Sexy Space is unusual because it also communicates with a central server, and so can be controlled by the hackers who created it. Zulfikar Ramzan, Symantec's technical director of security response, says that it has yet to be determined as to how Sexy Space will use the connection to the central server. "But this has all the makings of a mobile botnet," New Scientist magazine quoted him as saying. "As PC botnets go it's unsophisticated. But it's a new development in the world of mobile malware," added Ben Feinstein of SecureWorks, a computer security firm based in Atlanta, Georgia. The experts fear that infected mobile phones may also be misused to infiltrate computer networks. This fear stems from the fact that in a demonstration last year, a team from Errata Security, also in Atlanta, used an iPhone sent to a company to spy on its IT infrastructure. While sat in the firm's mailroom the phone sent back information about the local wireless systems and computers. A criminal hacker could use the same technique to break into a company's internal computer network, Errata's researchers claim.
Engineers working on converting foot power into battery power
Engineers are developing a way to capture the energy released by the marching boots of soldiers and are trying to use it to power their equipment, according to the latest research. The new system designed to convert foot-power into battery power could help troops reduce the weight of their packs by up to 10 kg. The project has been designed to address the needs of infantrymen. Heavy packs can severely limit a soldier's mobility and also lead to long-term health problems. The typical pack weight that an infantryman carries on a six-hour patrol is around 75 kg, with batteries making up 10 kg of the load. Essential kit such as ammunition and water make up much of the rest. A similar energy harvesting idea has been used in cars for some time where braking force is stored and later used to drive the vehicle forward. However, harvesting energy from people walking has always proved difficult due to the flexibility and strength of the materials required and the fact that everyone's walking patterns are different. The devices will use high tech ceramics and crystals as piezoelectric transducers in order to convert mechanical stress into an electric charge. Andrew Bell, professor at the University of Leeds, who is leading the project says: 'It could also reduce a soldier's pack weight by around 15 percent.' 'And this technology could potentially have lots of applications in civvy street too.' Bell says his team will succeed where others have failed because they are taking a holistic approach.
IPhone Apps For Road Warriors
As smart phones keep getting smarter, more and more road warriors are leaving their laptops behind, leaning instead on their trusty phones to keep up with work away from the office. With over 50,000 apps in the App Store emporium, the iPhone offers an especially rich trove of ammo for roaming productivity mavens to turn mobile phones into mobile offices.
In Pictures: 10 Top iPhone Apps For Road Warriors
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It's important to keep this little revolution in perspective: A new style of device requires a new set of work habits. Your glossy gadget can't match your laptop in every respect, and it's a mistake to try to use it the same way. No matter how blazingly fast your thumbs might be, pecking delicately away at a touch-screen keyboard won't win any speed records. Though some inevitably try, the iPhone's not a great tool for writing a novel.
In Pictures: Top 10 iPhone Apps For Road Warriors
Instead, the iPhone is a device of convenience and context. Unlike laptops, notebooks or messy collections of Post-It notes, your phone rarely leaves your side, making it a handy vessel for bottling brainstorms, managing to-dos and itineraries, or capturing on-the-go information like expenses or billable hours. The best iPhone apps (and especially the best productivity apps) emphasize quick access to your ideas, contacts, tasks and info. Most of them thrive on simplicity, offering fewer features than desktop counterparts, but also making it faster and easier to get it done quickly.
Take, for instance, the Quickoffice Mobile Office Suite. It lets you edit Word and Excel files and view a slew of others. Editing a long document on your iPhone may not be ideal--but being able to make changes on the go could be a lifesaver.
Compared to traditional computer work of long, sustained work sessions, iPhone office apps are tuned for short but frequent hits, encouraging you to capture new information and ideas as they happen, to be processed and massaged later. The iPhone is likewise ideal for reading and even editing documents in the otherwise lost time of grocery-store lines or subway commutes. (This also happens to be true of iPhone games, which are nearly all designed for quick but tasty bites of gameplay, just a few minutes at a time.) In all of its contexts, in other words, the device's quick-draw convenience lets you make the most of your downtime, whether you use it for work, play or creative contemplation.
This makes the iPhone an ideal laptop substitute between the times we traditionally consider work time, and as a can-do sidekick outside the office--at conferences, for business travel or in those sparkling (and never scheduled) moments when inspiration strikes.
We've collected the best apps for making the most of those intrawork interludes, each of them earning their place with fast, efficient interfaces that are well suited to this evolving style of work.
Grab 'em--and go.
In Pictures: Top 10 iPhone Apps For Road Warriors
Josh Clark stress-tested thousands of iPhone apps to identify the 200+ apps featured in his book, Best iPhone Apps: The Guide for Discriminating Downloaders, available this month from O’Reilly Media . When he’s not tapping, flicking and swiping, he makes words and spins code at his hypertext laboratory www.globalmoxie.com in Paris, France.
