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Sunday, November 16, 2008

Swarms of small satellites coming soon

Posted by Roland Piquepaille

The first satellites were launched about 50 years ago as a way to conquer space. Now, satellites are essential for our civilian and military communications. But they remain large and expensive, some of them costing several hundreds of millions of dollars. This is why researchers from the University of Florida (UF) are building small satellites able to work as a team to take multiple and distributed measurements or observations of weather phenomena for example. These small satellites should cost only about $100,000 to produce. The first one should be launched next year by a NASA rocket and should not be larger than a softball. The goal is to mass-produce these satellites to even reduce their costs. But read more…

Benefits of multi-satellite systems

The picture above shows the expected benefits of multi-satellite systems. (Credit: University of Florida) Here is a link to a larger version of this chart.

Prototype of a UF small satellite

And you can see above “a prototype of a ‘pico satellite’ being designed and built in a mechanical and aerospace engineering laboratory at the University of Florida. […] The completed pico satellite, nicknamed SwampSAT, expected to be launched in 2009, will be about the size of a softball. This prototype is slightly larger than a basketball.” (Credit: University of Florida) Here is a link to several other pictures of these small satellites and the man behind them.

This research project has been initiated by Norman Fitz-Coy, an associate professor of mechanical and aerospace engineering. Fitz-Coy is also the director of the Advanced Space Technologies Research & Education Center (ASTREC) established by the U.S. National Science Foundation (NSF) at the UF College of Engineering.

But will these $100K small satellites replace $100M ones? Not at all. “Fitz-Coy said small satellites are not anticipated to totally replace larger ones, but rather to complement them by adding new capabilities. For example, he said, ’swarms’ of small satellites could take multiple, distributed measurements or observations of weather phenomena, or the Earth’s magnetic fields, providing a more comprehensive assessment than is possible with a single satellite. ‘People are looking toward these to not totally replace the big satellites but to supplement what the big satellites are doing,’ he said.”

It’s interesting to note that it’s easier to control large satellites than small ones. Fitz-Coy uses an analogy with cars. “The smaller the satellite, the harder it is to manage its flight path and attitude, or orientation in space — for example, which directions its instruments point, a critical parameter in spacecraft design. ‘It’s similar to you driving an SUV down the road or a sub-compact,’ Fitz-Coy said, explaining that while inertia helps large satellites, it is not enough to keep small satellites on track and properly oriented. ‘The SUV is a lot more stable than the sub-compact.’” Yes, but it costs more…

So what will happen in the short term? The first launch should happen in 2009 “aboard an unmanned NASA rocket carrying other payloads as well. The satellite will fly at an altitude of between 600 and 650 kilometers, or from 373 to 404 miles, and will remain in orbit for several years, Fitz-Coy said. A container that could be standardized for use in transporting the small satellites aboard the rocket also is being developed. As with the satellites themselves, the goal is mass production – to be able to transport satellites to outer space much the same way that ships and trucks transport goods around the terrestrial world now, Fitz-Coy said.”

Sources: University of Florida News, November 13, 2008; and various websites

You’ll find related stories by following the links below.

Roland Piquepaille lives in Paris, France, and he spent most of his career in software, mainly for high performance computing and visualization companies. For disclosures on Roland's industry affiliations, click here.

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Urine passes Nasa taste test

By Irene Klotz
Cape Canaveral, Florida

Drinking beverage
Mmm... tasty. But will astronauts enjoy the taste of their own urine recycled?

Astronauts flying aboard space shuttle Endeavour on Saturday plan to deliver a device to the International Space Station that may leave you wondering if Nasa is taking recycling too far.

Among the ship's cargo, which will help prepare the station for an expanded six-person crew, is a water regeneration system that, as one astronaut puts it, "will make yesterday's coffee into today's coffee".

"It's one of these great circle-of-life things," explained Don Pettit, a former space station science officer serving as a mission specialist aboard Endeavour.

The new system distils, filters, ionizes and oxidizes wastewater - including urine -- into fresh water for drinking.

I've got some in my fridge. It tastes fine to me
Bob Bagdigian,

Nasa

The US space agency wasn't really thinking about saving the environment when it decided to invest $250m in the water recycling gear.

With the space shuttles due to retire in two years, Nasa needed another way to make sure the station crew would have a good supply of fresh water.

The orbiters make water as a byproduct of their electrical systems. On missions to the space station, the water is bagged and transferred over to the outpost for storage.

"When the shuttles retire, that nice water-delivery system that we have will go away," said Endeavour astronaut Sandra Magnus, who will be staying behind on the station for a four-month flight.

"In addition we're going to have six people on-station, so our requirements for water will go up."

Ms Magnus replaces Nasa astronaut Greg Chamitoff, who has been aboard the station since June.

Astronaut sees reflection in spilled liquid
Every drop of water on board the ISS is precious

Nasa doesn't plan to start using the new system immediately - engineers want samples to analyse to make sure it functions properly in zero-gravity.

The water has been thoroughly tested on Earth, including blind taste tests that pitted recycled urine with similarly treated tap water.

People may think it's disgusting, but if it's done correctly the water is purer than you drink on Earth
Heidemarie Stefanyshyn-Piper,

Endeavour astronaut

"Some people may think it's downright disgusting, but if it's done correctly, you process water that's purer than what you drink here on Earth," said Endeavour astronaut Heidemarie Stefanyshyn-Piper.

The most frequent comment was the faint taste of iodine in the water, added Nasa's Bob Bagdigian, who oversaw development of the water regeneration system.

Iodine is added at the final step of the process to control microbial growth.

"Other than that, it is just as refreshing as any other kind of water," Mr Bagdigian said.

"I've got some in my fridge. It tastes fine to me."

International Space Station
The International Space Station is also being fitted with an extra bathroom unit

Nasa plans to double the station's crew size from three to six as early as May.

Endeavour also will be delivering two new sleeping compartments, more exercise gear, a galley and perhaps most important, a second toilet.

"With six people, you really do need to have a two-bathroom house. It's a lot more convenient and a lot more efficient," Ms Magnus said.

Astronauts also plan to work on the space station's solar power system. Four spacewalks are scheduled to begin repairs on a contaminated rotary joint needed to aim solar panels at the Sun.

The flight is the fourth and final mission of the year.

Nasa had hoped to fly a servicing call to the Hubble Space Telescope last month but delayed the mission to May 2009 to prepare for some additional repair work on the observatory.

In all, Nasa plans 10 more shuttle flights before the fleet is retired in 2010.

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Facial scars can help win a woman's heart

By Roger Dobson

Faced with picture of men with and without different scars, women rated the scarred faces as better looking, but scars did not enhance women's attractiveness to men.

"This is the first study to demonstrate that under certain circumstances post-traumatic scarring may increase a person's perceived social worth,'' say the researchers from the universities of Liverpool and Stirling.

"Our results suggest that under certain circumstances scars may advertise valued information about their bearers, and that the idea that scarring universally devalues social perceptions can no longer be assumed to be true."

In the study, published in the journal Personality and Individual Differences, around 220 people were asked to look at pictures of men and women, some of which had been manipulated to have different scars.

Results show that scarring enhances women's ratings of men's attractiveness for short-term, but not for long-term, relationships. Men's ratings of female attractiveness were unaffected by scarring.

Exactly why women favour scars is not clear, but one theory is that they provide visible evidence of past trauma and may also communicate information about the man's history and personality, as well as affect their attractiveness.

It has also been suggested that scarring associated with violence may signal to a woman that the man has a risk-taking personality or above average masculinity, both of which might appeal to women for short term relationships. Because of that, scars may indirectly be a sign of good genes or a strong immune system that also appeal to women for short-term relationships.

The scars that are rated attractive are those that appear to be associated with post traumatic events or violence of some kind.

"Scars that indicate past illness like chickenpox, acne, or surgery scars, and which therefore suggest a weaker immune system, may be viewed more negatively than other types of scarring," says the report.

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Debate: Which is the world's most invaluable species?

Plankton, bats, primates, fungi and bees - which species would have the greatest impact on our planet if it were lost? Five experts set out their case public debate in London next Thursday

Jessica Aldred

Fungi
'It keeps the trees alive, recycles waste and helps us'
Professor Lynne Boddy of the Cardiff School of Biosciences

Earthwatch debate: Amanita pantherina wild mushroom

Fungi have a bad reputation, usually being thought of as poisoners, rotters of food and homes, causes of plant disease and human infections (eg athlete's foot). In fact, very few fungi cause a nuisance. Moreover, without fungi humans could not exist. Most terrestrial plants obtain their nutrients and water from soil through fungi associated with their roots. Furthermore, fungi are the main garbage disposal agents and nutrient recyclers of the natural world. They are hugely important as food for soil animals and in producing human food, eg Quorn, cheese, chocolate and soft drinks. Fungi produce many "wonder drugs" including penicillin and statins to control cholesterol.

Within this vast kingdom of organisms that is so crucial to our very existence, it is hard to single out just one species. However, my choice would be Amanita muscaria, the fly agaric. This fungus forms mycorrhizas with the roots of forest trees, providing them with water, mineral nutrients, protection from pathogens and some pollutants. It also recycles dead organic matter. It is used as a food source by some animals, and produces powerful chemicals that may turn out to yield novel pharmaceuticals.

Bees
'Bees are irreplaceable. Their loss will be catastrophic'
Dr George McGavin of the Oxford University Museum of Natural History

Honeybee

The partnership between flowering plants and pollinating insects, especially bees, is one of the most widespread and significant symbiotic interactions on Earth. This 100m-year-old collaboration has spawned a rich diversity of species and promoted the rise to dominance of humans.

Now the need to feed our burgeoning population, coupled with the agricultural means to that end – a plethora of pesticides, the unabated loss of natural habitat and the translocation of alien species and diseases - are driving wild and managed bee populations into a very steep decline. Seventy percent of the crop species eaten by humans depend wholly or partly on pollination and recent estimates put the economic value of insect pollination at over £121 billion ($192bn) - representing at least 10% of the value of the world's agricultural production.

Bees are irreplaceable and the debate about what might happen if they disappeared is no longer academic. We have set in motion processes that may lead to the extinction of the planet's most important pollinators along with countless other species that depend on them. Not only will the world be a much less colourful place, it will also be poorer in every other way imaginable. The effects will be nothing short of catastrophic.

Plankton
'Plankton are the base of the whole food web'
Professor David Thomas of the School of Ocean Sciences, University of Bangor

Earthwatch debate: Plankton

Plankton is a collective term for a myriad of bacteria, viruses, plant-like microbes and small animals that drift at the mercy of the winds and the ocean currents and wind. They are the base of the whole food web that lives in just about any body of water you care to imagine: from your bird bath in the garden up to the vast oceans that cover most of the planet.

Temperature extremes hold no bounds and plankton survive being encased in ice in our Arctic and Antarctic oceans and can survive near boiling waters in hot springs. Not only that, but plankton cells can be carried large distance in aerosols in the wind, and some people even believe they can survive in space. They not only fuel aquatic ecosystems, but some release gases that can influence cloud formation and therefore global climate.

But apart from how vital the plankton are to running planet Earth, they are simply beautiful to look at. Plankton have been an inspiration to artists and designers ever since the first microscopes were invented, and plankton inspired design can be found on a whole range of scales from buildings to wheel hubs.

Bats
'Bats provide a number of these essential services'
Dr Kate Jones of the Zoological Society of London

Earthwatch debate: Bats

We are in the midst of a mass extinction of this planet's life brought about by humans monopolising global resources and changing global climate patterns. Many species provide essential services eg, disease control, clean water, pollination and insect regulation, and we are now faced with an agony of choice. Given finite amounts of conservation dollars, which species can we not do without? I present the case for bats.

Bats provide a number of these essential services; for example without bats many commercially important crops such as bananas, mangoes, dates and tequila would fail. Insects consumed by bats translate to millions of dollars saved on pesticides. Bats are also indicators of general ecosystem health and monitoring their populations provides us with early warning systems of irreversible damage.

Bats also have many irreplaceable traits, they are the only mammals to use powered flight, can hunt and navigate in the pitch darkness using only sonic echoes, provide the imagery of Dracula and the flying creatures of Halloween. Perhaps some of us couldn't cope with fewer fungi in our lives, green goo in our rivers, bees to sting and annoy, and primates that one day might rise to overthrow us, but to me a world without bats is unthinkable.

Primates
'Primate habitats provide ecosystem services we all depend upon'
Ian Redmond, chief consultant of the great apes survival project

Earthwatch debate: Gorilla

Monkeys, apes and lemurs must be saved, not just because they share so much DNA with humans (although blood is thicker than water, so this convinces many people), not because they are fascinating research subjects (though clearly they are), not because they are intelligent social mammals who have every right to exist (though arguably they do); not even because primate-watching can form the basis of multimillion-pound tourist industries, creating jobs and lifting rural communities out of poverty.

Any one of these would be reason enough to fight for the survival of our zoological next-of-kin, but I would argue that their ecological role as keystone species in tropical and sub-tropical forests is more important.

Primate habitats provide ecosystem services we all depend upon – especially absorbing carbon while releasing oxygen through photosynthesis and pumping water into the atmosphere through evapo-transpiration, which drives global rainfall patterns. What most people fail to recognise, however, is that primates sow the trees of tomorrow by dispersing seeds in their dung.

If we want these forests to be a permanent carbon store, a source of clean water and to regulate our climate in future, we had better not kill the gardeners of the forest today.

• The Earthwatch debate Irreplaceable - the world's most invaluable species, takes place from 7-9pm at the Royal Geographical Society in London on Thursday November 20. Free to current Earthwatch supporters, but by ticket only. For all others, a donation will be requested on the door. Doors open 6pm (cash bar). The debate will be followed by an optional buffet supper with wine, £25. For tickets and information please call +44 (0)1865 318856 or email events@earthwatch.org.uk

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Mineral Kingdom Has Co-evolved With Life, Scientists Find


Elrathii kingii trilobite from the middle Cambrian period, approximately 550 million years BCE. Found in a sandy shale formation south of Salt Lake City, Utah. (Credit: iStockphoto/Russell Shively)

Evolution isn't just for living organisms. Scientists at the Carnegie Institution have found that the mineral kingdom co-evolved with life, and that up to two thirds of the more than 4,000 known types of minerals on Earth can be directly or indirectly linked to biological activity.

The finding, published in American Mineralogist, could aid scientists in the search for life on other planets.

Robert Hazen and Dominic Papineau of the Carnegie Institution's Geophysical Laboratory, with six colleagues, reviewed the physical, chemical, and biological processes that gradually transformed about a dozen different primordial minerals in ancient interstellar dust grains to the thousands of mineral species on the present-day Earth. (Unlike biological species, each mineral species is defined by its characteristic chemical makeup and crystal structure.)

"It's a different way of looking at minerals from more traditional approaches," says Hazen. "Mineral evolution is obviously different from Darwinian evolution—minerals don't mutate, reproduce or compete like living organisms. But we found both the variety and relative abundances of minerals have changed dramatically over more than 4.5 billion years of Earth's history."

All the chemical elements were present from the start in the Solar Systems' primordial dust, but they formed comparatively few minerals. Only after large bodies such as the Sun and planets congealed did there exist the extremes of temperature and pressure required to forge a large diversity of mineral species. Many elements were also too dispersed in the original dust clouds to be able to solidify into mineral crystals.

As the Solar System took shape through "gravitational clumping" of small, undifferentiated bodies—fragments of which are found today in the form of meteorites—about 60 different minerals made their appearance. Larger, planet-sized bodies, especially those with volcanic activity and bearing significant amounts of water, could have given rise to several hundred new mineral species. Mars and Venus, which Hazen and coworkers estimate to have at least 500 different mineral species in their surface rocks, appear to have reached this stage in their mineral evolution.

However, only on Earth—at least in our Solar System—did mineral evolution progress to the next stages. A key factor was the churning of the planet's interior by plate tectonics, the process that drives the slow shifting continents and ocean basins over geological time. Unique to Earth, plate tectonics created new kinds of physical and chemical environments where minerals could form, and thereby boosted mineral diversity to more than a thousand types.

What ultimately had the biggest impact on mineral evolution, however, was the origin of life, approximately 4 billion years ago. "Of the approximately 4,300 known mineral species on Earth, perhaps two thirds of them are biologically mediated," says Hazen. "This is principally a consequence of our oxygen-rich atmosphere, which is a product of photosynthesis by microscopic algae." Many important minerals are oxidized weathering products, including ores of iron, copper and many other metals.

Microorganisms and plants also accelerated the production of diverse clay minerals. In the oceans, the evolution of organisms with shells and mineralized skeletons generated thick layered deposits of minerals such as calcite, which would be rare on a lifeless planet.

"For at least 2.5 billion years, and possibly since the emergence of life, Earth's mineralogy has evolved in parallel with biology," says Hazen. "One implication of this finding is that remote observations of the mineralogy of other moons and planets may provide crucial evidence for biological influences beyond Earth."

Stanford University geologist Gary Ernst called the study "breathtaking," saying that "the unique perspective presented in this paper may revolutionize the way Earth scientists regard minerals."

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51 Countries to Form International Agency Promoting Renewable Energy

Don’t Call it a Wind Farm, It’s an EcoPower Centre: Canada’s Largest Wind Project (200 MW) Opens

by Matthew McDermott, Brooklyn, NY

melancthon wind farm photo

photo: Canadian Hydro

Though in the scheme of the world it’s solidly in the middle ranks of wind power project capacity, but given that the newly finished Melancthon EcoPower Centre, developed by Canadian Hydro, is Canada’s largest wind farm it’s still worth noting. Here are the details:

Under Construction Since 2005
Located near Shelburne, Ontario (northwest of Toronto), the Melancthon EcoPower Centre has a capacity of 199.5 MW and has been under construction since 2005. It commenced initial commercial operations after the 67.5 MW first phase was completed in in 2006. The final phase, which brought the project to its current nation-leading capacity, began construction in 2007.

All the electricity from the project is being sold to the Ontario Power Authority under two 20-year contracts.

Canadian Hydro says that it expects the wind farm’s annual output to be about 545 GWh, or enough power for 70,000 homes.

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