Artist's conception of an fragment as it blasts off from Mars. Boulder-sized planetary fragments could be a mechanism that carried life between Mars and Earth, UA planetary scientist Jay Melosh says. (Credit: The Planetary Society)
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As long as we’re still pondering human origins, we may as well entertain the idea that our ancestor microbes came from Mars.
And Jay Melosh, a planetary scientist from the University of Arizona in Tucson, is ready with a geologically plausible explanation.
Meteorites.
“Biological exchange between the planets of our solar system seem not only possible, but inevitable,” because of meteorite exchanges between the planets, Melosh said. “Life could have originated on the planet Mars and then traveled to Earth.”
Jay Melosh. Credit: Maria Schuchardt, University of Arizona Lunar and Planetary Lab
Melosh is a long-time researcher who says he’s studied “geological violence in all its forms.” He helped forge the giant impact theory of the moon’s formation, and helped advance the theory that an impact led to the extinction of the dinosaurs 65 million years ago.
He points out that Martian meteorites have been routinely pummeling Earth for billions of years, which would have opened the door for past Mars microbes to hitch a ride. Less regularly, Earth has undergone impacts that sent terrestrial materials flying, and some of those could have carried microbes toward the Red Planet.
“The mechanism by which large impacts on Mars can launch boulder-sized surface rocks into space is now clear,” he said. He explained that a shock wave spreads away from an impact site faster than the speed of sound, interacting with the planetary surface in a way that allows material to be cast off – at relatively low pressure, but high speed.
“Lightly damaged material at very high speeds,” he said, “is the kind of environment where microorganisms can survive.”
Scientists have recent evidence of Earth microbes surviving a few years in space. When the Apollo 12 astronauts landed on the moon, they retrieved a camera from Surveyor 3, an unmanned lander that had touched down nearly three years prior. Earthly microbes – including those associated with the common cold — were still living inside the camera box.
“The records were good enough to show one of the technicians had a cold when he was working on it,” he said.
Scientists also have evidence that microbes can survive for thousands or even hundreds of thousands of years when frozen on Earth, but surviving that long in space would be an entirely different matter, with the bombardment of UV light and cosmic rays. Then again, the microbe Dienococcus radiodurans is known to survive in the cores of nuclear reactors.
Melosh acknowledges that scientists lack proof that such an exchange has actually occurred between Mars and Earth — but science is getting ever closer to being able to track it down.
LEAD PHOTO CAPTION: Artist’s conception of an fragment as it blasts off from Mars. Boulder-sized planetary fragments could be a mechanism that carried life between Mars and Earth, UA planetary scientist Jay Melosh says. (Painting by Don Davis. Copyright SETI Institute, 1994)
With less than six weeks to go, more than 500 cities around the world have officially agreed to go dark in support of global action on climate change. On March 28, 2009 at 8:30 p.m., local time, World Wildlife Fund is asking individuals, businesses, governments and organizations around the world to turn off their lights for one hour — Earth Hour — to make a global statement of concern about climate change and to demonstrate their commitment to finding solutions. Step inside and find out how you can become a part of this historic event…
Wherever you happen to be in the world on March 28th at 8:30 p.m., you’re likely to find a city or community somewhere nearby that is making plans to turn out the lights for Earth Hour – a global goal of 1,000 cities! WWF’s initiative aims to increase awareness about climate change and demonstrate that people from all over the world care about the issue. “Climate change and what we do about it is going to transform the world much more rapidly than people realize.” say Richard Moss, Vice President and Managing Director for Climate Change. “It’s my goal to get us moving to a world we will want, not one we’ll regret leaving for our children and grandchildren.”
Before you start knocking “Earth Hour” as something that just won’t make a difference, take just a moment of your time and watch this, please…
And now, here are some highlights of what’s going on around Earth Hour 2009 as we count down the days…
NASHVILLE: Earth Hour launched in Music City with a musical press conference that included live performances by Nashville superstars pledging to turn out against climate change.
THE STARS AND STRIPES ARE ALIGNING: Houston, TX; Santa Rosa, CA; St Louis, MO; Sarasota, FL; Minneapolis, MN; and Valdosta, GA signed up to be part of Earth Hour 2009. They join Atlanta, Chicago, Dallas, Las Vegas, Los Angeles, Miami, Nashville, New York City and San Francisco.
NOBEL PEACE PRIZE WINNER ARCHBISHOP DESMOND TUTU ANNOUNCES HIS SUPPORT: “Climate change is the greatest human induced crisis facing the world today. It is totally indiscriminate of race, culture and religion. It affects every human being on the planet. Earth Hour is an opportunity for every man, woman and child from all corners of the globe to come together with a united voice and make a loud and powerful statement on the issue of climate change.”
BACK TO MY OLD SCHOOL: The University of Miami became the first American campus to officially sign up to turn off, but was quickly joined by Michigan State, University of Nevada, Las Vegas, University of Virginia, Belmont, Columbia, Ohio University, Howard University, Georgia Tech, Northwestern, Spellman, University of Missouri, St. Louis and Vanderbilt.
I GOT THE POWER: 10,000 college students from across the nation will converge on Washington DC on February 27–March 2 for Power Shift ’09, asking for “bold, comprehensive and immediate federal climate action.” Earth Hour Project Director Meg Pearce and Campus Organizer Sophie Latham will be there holding a special session on how to be part of Earth Hour 2009, the largest global climate event in history.
CITY OF LIGHTS TO TURN LIGHTS OFF IN SUPPORT OF WWF’S EARTH HOUR 2009: Paris—known as the City of Lights—will lead a list of 28 cities and towns across France that have committed to join the world in making a visual vote for decisive action on climate change by turning off their lights for one hour during Earth Hour 2009 on March 28th.
LAS VEGAS FLICKS THE SWITCH FOR EARTH HOUR 2009: Officials from World Wildlife Fund joined Clark County, Nevada Commissioner Lawrence Weekly, City of Las Vegas Mayor Oscar B. Goodman and City of Henderson Mayor James B. Gibson at the iconic “Welcome to Fabulous Las Vegas” sign to officially kick off the Las Vegas Valley’s participation in Earth Hour–a global event calling for action on climate change.
For now? Be sure to visit the Earth Hour website, where you can sign up to show your support and find all kinds of wonderful tools and ideas on how to motivate your community, school, family and friends to pledge just one hour of their time to darkness and become part of this global event.
Don’t forget to mark your calendar…Earth Hour is March 28, 2009, at 8:30 pm. Be there with us when the lights go out…
Solar Collecting Satellite. Image courtesy of Mafic Studios.
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Is space-based solar power (SBSP) a technology whose time has come? The concept and even some of the hardware for harnessing energy from the sun with orbiting solar arrays has been around for some time. But the biggest challenge for making the concept a reality, says entrepreneur Peter Sage of Space Energy, Inc., is that SBSP has never been commercially viable. But that could be changing. Space Energy, Inc. has assembled an impressive team of scientists, engineers and business people, putting together what Sage calls “a rock-solid commercial platform” for their company. And given the current looming issues of growing energy needs and climate change, Space Energy, Inc. could be in the right place at the right time.
“Although it’s a very grandiose vision, it makes total sense,” Sage told Universe Today. “This is an inevitable technology; it’s going to happen. If we can put solar panels in space where the sun shines 24 hours a day, if we have a safe way of transmitting the energy to Earth and broadcasting it anywhere, that is a serious game changer.” If everything falls into place for this company, they could be producing commercially available SBSP within a decade.
The basic concept of SBSP is having solar cells in space collecting energy from sun, then converting the energy into a low intensity microwave beam, sending it down to Earth where it is collected on a rectenna, and then fed into the power grid to provide electricity. Almost 200 million gigawatts of solar energy is beamed towards the Earth every second, which is more energy than our civilization has used since the dawn of the electrical age. We only need a way to harness that energy and make it usable.
Space Energy, Inc.’s vision is to help create an energy-independent world, and improve the lives of millions of people by bringing a source of safe, clean energy to the planet from space. They are looking to become the world’s leading, and perhaps the first, SBSP enterprise. Solar collector beaming energy to Earth. Image courtesy Mafic Studios.
“The biggest challenge for SBSP is making it work on a commercial level in terms of bottom line,” said Sage, “i.e., putting together a business case that would allow the enormous infrastructure costs to be raised, the plan implemented, and then electricity sold at a price that is reasonable. I say ‘reasonable’ and not just ‘competitive’ because we’re getting into a time where selling energy only on a price basis isn’t going to be the criteria for purchase.”
Currently, there are times in the US when electricity is sold wholesale for close to a dollar a kilowatt during peak usage or times of emergency when power needs to be shipped around the national grid. Sage said SBSP will never be cost comparable with the current going rate of 6 or 7 cents a kilowatt due to the enormous set-up costs.
“We believe we can get it to a reasonable price, a fair market price as the demand for energy increases,” Sage said.
A huge energy gap is looming for our world, and that too, will change the energy game.
According to a white paper written by aerospace engineer James Michael Snead, “The End of Easy Energy and What Are We Going To Do About It,” in order to meet the world’s projected increase in energy needs by 2100 which likely will be at least three times what is being produced today, today’s sustainable energy production must expand by a factor of over 25. Under that scenario, even if the US were to build 70 new nuclear plants, add the equivalent of 15 more Hoover Dams, expand the geothermal capacity by 50 times what it is today, install over a million large land or sea wind turbines covering 150,000 square miles, build 60,000 square miles of commercial solar voltaic farms, and on top of that convert 1.3 billion dry tons of food mass to bio fuels, still only 30% of the power needs would be filled by 2100, or perhaps even earlier.
“Looking at every single technology we can as a civilization to try and fill the energy gap in a clean and resourceful, sustainable way, technologies like SBSP have to be made to work,” said Sage. Peter Sage. Image courtesy Space Energy, Inc.
He says this is an important point. “We’re not setting ourselves up to compete with coal, or nuclear, or ground based solar or wind. I don’t want to pick a fight with any of those industries saying that we’re trying to take a piece of their pie. What we’re saying is that right now, from a responsible perspective in terms of being a good steward for the environment, we need to look at every single source of energy that we can get our hands on, primarily green, and develop it regardless, because we’re going to need it. SBSP is one of the few forms of energy that has the ability to be base-load, i.e., 24-7, and it’s the only form of energy that can be broadcast on demand.”
The first phase of Space Energy, Inc.’s plan is to launch a small prototype satellite into low Earth orbit. “This will help validate the numbers we are speculating on at this point, but also validate several different aspects of what SBSP can do,” said Sage. “From a successful demonstration, we are hoping to close power purchase agreements with one of several entities we are in discussions with at present. And on the strength of that we should be able to put the first commercial satellite in orbit.”
With regards to the timetable, Sage was hesitant to commit to a schedule. “As timetables go, everything needs to be flexible, but we are looking to close the financing for the demonstrator during the first quarter of this year (2009). The demonstrator is a 24 to 36 month project and, from there, we will start the commercial build-out of the main satellite, which could take up to four years to be operational.”
Satellites in orbit collecting solar power. Image: National Space Society.
That’s an aggressive schedule. But Sage said since their plan is being driven from a commercial basis, they can run their operation differently than government agencies who don’t necessarily operate with the bottom line in mind. “Our board members and entrepreneurial group certainly have a lot of experience running commercial entities. We know what we’re doing. We’re in a market that we hope to pioneer, and everyone feels confident that we have what it takes. We certainly have the passion, vision and enthusiasm to make this happen.”
What are the biggest hurdles to overcome in this project? “If you would have asked me that question a few months ago,” Sage replied, “I would have said a combination of meeting the right people who could understand the vision and scope of what it is what we’re doing, and raising the initial financing for the demonstrator. Those hurdles, at this point, really seem to be taken care of. The more we have our technical teams talk with investors, the more people understand that we’re real and this isn’t some sort of Star Trek giggle factor. Right now, with the level of due diligence that’s been done not only on SBSP itself, but with ourselves as a commercially viable entity, we’re on the forefront of many people’s agenda in terms of how to move this forward. We see a straight path to making this a reality.”
Sage said no new technology is needed for the demonstrator, which will be a working, small prototype, but challenges do remain to move forward beyond that. “Obviously, there are technical challenges because something of this scale has never been done before. We know we can do wireless power transmission, as NASA did some pretty significant tests on this in the 1970s. We know the physics of wireless power transmission, and how everything should work from geostationary orbit.”
While the demonstrator won’t be of any scale where energy could be sold commercially, it would be a proof of concept.
“Once we’ve demonstrated that we can wirelessly beam power accurately to the ground in a safe, controlled, effective manner, and in a way that can be metered and measured,” said Sage, “we will have taken a massive step forward to prove that SBSP is a technology of the future that has the potential to really fill a gap in the world’s energy needs.”
Some have equated developing SBSP to what was accomplished with the Apollo program.
“There are so many positive spinoffs to SBSP as a game changing foundation of space commerce, that just by addressing a lot of the challenges that lay ahead, we will be blazing a trail for many other opportunities for a low earth orbit economy,” Sage added. A rectenna on Earth collects microwaved energy from space solar collectors. Image courtesy Mafic Studios.
Space Energy, Inc. recently attended the World Future Energy Summit and has been overwhelmed with the response.
“We’ve had discussions with many different entities, both governmental and private, in the Middle East; Abu Dhabi, United Arab Emirates, Jordan, Dubai, many areas around Europe, and many of the world’s top investment firms. I don’t think we’re going to be short of people that will want to support us.” Sage added that in general, SBSP has strong support in Washington DC, and that SBSP recently was added to a list of technologies being studied by the Obama administration.
SBSP has ability to literally change the course of history, and impact the quality of life for people everywhere. Sage said this project is an entrepreneurs’ dream.
“I speak for our entire team here, we’re not just focused on how much money are we going to make,” Sage said. “We’re focused on the fact that this is an inevitable technology and someone is going to do it. Right now we’re the best shot. We’re also focused on the fact that, according to every scenario we’ve analyzed, the world needs space based solar power, and it needs it soon, as well as the up-scaling of just about every other source of renewable energy that we can get our hands on.”
“Space based solar power will happen whether we crack cold fusion, or whether we suddenly go to 80% efficiency on ground based solar power (currently its only at 50%),” Sage continued. “It has to happen based on the nature on what it is. With that in mind, I’ve been willing to put everything I have on the line to be able to make this work, and that was three years, ago. To see how far we’ve come in the past six to eight months has been amazing.”
Scientists have long suspected that climatic variables like sea surface temperature and precipitation could foreshadow outbreaks of disease. Now, they have confirmation.
Responding to a deadly 1997 outbreak of the mosquito-borne disease Rift Valley fever, researchers had developed a “risk map,” pictured above, using NASA and National Oceanic and Atmospheric Administration measurements of sea surface temperatures, precipitation, and vegetation cover. As reported in a recent NASA-led study, the map gave public health officials in East Africa up to six weeks of warning for the 2006-2007 outbreak of the deadly Rift Valley fever in northeast Africa — enough time to lessen human impact.
On the map above, pink areas depict increased disease risk, while pale green areas reflect normal risk. Yellow dots represent reported Rift Valley fever cases in high-risk areas, while blue dots represent occurrences in non-risk areas. The researchers have detailed the map’s effectiveness in the Proceedings of the National Academy of Sciences.
Scientists study a typical dambo habitat at Sukari Farm, a long-term Rift Valley Fever study site just outside Nairobi, Kenya. Dambos are natural breeding grounds for disease-carrying mosquitoes and can be observed from space with the aid of satellites. Credit: Assaf Anyamba
During an intense El Niño event in 1997, the largest known outbreak of Rift Valley fever spread across the Horn of Africa. About 90,000 people were infected with the virus, which is carried by mosquitoes and transmitted to humans by mosquito bites or through contact with infected livestock. That outbreak prompted the formation of a working group — funded by the U.S. Department of Defense Global Emerging Infections Surveillance and Response System — to try to predict future outbreaks.
The working group didn’t start from scratch. The link between the mosquito life cycle and vegetation growth was first described in a 1987 Science paper by co-authors Kenneth Linthicum of the U.S. Department of Agriculture and Compton Tucker of NASA’s Goddard Space Flight Center. Later, a 1999 Science paper described a link between Rift Valley fever and the El Niño-Southern Oscillation, a cyclical, global phenomenon of sea surface temperature changes that can contribute to extreme climate events around the world.
Building on that research, Assaf Anyamba of NASA Goddard and the University of Maryland, and his colleagues, set out to predict when conditions were ripe for excessive rainfall — and thus an outbreak. They started by examining satellite measurements of sea surface temperatures. One of the first indicators that El Niño will boost rainfall is a rise in the surface temperature of the eastern equatorial Pacific Ocean and the western equatorial Indian Ocean. Perhaps the most telling clue is a measure of the mosquito habitat itself. The researchers used a satellite-derived vegetation data set that measures the landscape’s “greenness.” Greener regions have more than the average amount of vegetation, which means more water and more potential habitat for infected mosquitoes. The resulting risk map for Rift Valley fever, showing areas of anomalous rainfall and vegetation growth over a three-month period, is updated and issued monthly as a means to guide ground-based mosquito and virus surveillance.
As early as September 2006, the monthly advisory from Anyamba and colleagues indicated an elevated risk of Rift Valley fever activity in East Africa. By November, Kenya’s government had begun collaborating with non-governmental organizations to implement disease mitigation measures—restricting animal movement, distributing mosquito bed nets, informing the public, and enacting programs to control mosquitoes and vaccinate animals. Between two and six weeks later—depending on the location—the disease was detected in humans.
After the 2006-2007 outbreak, Anyamba and colleagues assessed the effectiveness of the warning maps. They compared locations that had been identified as “at risk” with the locations where Rift Valley fever was reported. Of the 1,088 cases reported in Kenya, Somalia, and Tanzania, 64 percent fell within areas delineated on the risk map. The other 36 percent of cases did not occur within “at risk” areas, but none were more than 30 miles away, leading the researchers believe that they had identified most of the initial infection sites.
The potential for mapping the risk of disease outbreaks is not limited to Africa. Previous research has shown that risk maps are possible whenever the abundance of a virus can be linked to extremes in climate conditions. Chikungunya in east Africa and Hantavirus and West Nile virus in the United States, for example, have been linked to conditions of rainfall extremes.
“We are coming up on almost 30 years of vegetation data from satellites, which provides us with a good basis for predicting,” said Linthicum, co-author on the 1987 paper, upon his return from a Rift Valley fever workshop in Cairo, Egypt last month. “At this meeting, it was clear that using this tool as a basis for predictions has become accepted as the norm.”
The European Space Agency’s Soil Moisture and Ocean Salinity (SMOS) satellite has been cleared for takeoff, following nearly a year in limbo while the mission team awaited the go-ahead from a private launch company.
Originally expected to launch in 2008, SMOS has been in storage at Thales Alenia Space’s facilities in Cannes, France since last May, awaiting a launch appointment at the Russian Plesetsk Cosmodrome, north of Moscow. If all goes according to plan, the craft will now launch between July and October, the second ESA mission in a series of six designed to observe Earth from space and bolster an understanding of climate change. The first of the satellites in its new Living Planet Program, The Gravity field and steady-state Ocean Circulation Explorer (GOCE), is scheduled to go up March 16.
Over its lifetime of about 20 months, GOCE will map global variations in the gravity field – crucial for deriving accurate measurements of ocean circulation and sea-level change, both of which are affected by climate change.
SMOS, circulating at a low orbit of around 750 km (466 miles) above the Earth, will be the first mission dedicated to mapping soil moisture and ocean salinity. Salinity in the oceans has a significant impact on ocean circulation, which in turn helps drive the global climate. Among other applications, understanding the salinity and temperature of the seas will lead to easier predictions of the zones where hurricanes intensify. A specialized radiometer has been developed for the mission that is capable of observing both soil moisture and ocean salinity by capturing images of emitted microwave radiation around the frequency of 1.4 GHz (L-band). SMOS will carry the first-ever, polar-orbiting, space-borne, 2-D interferometric radiometer. The mission is designed to last three years.
Here’s a rundown of the final four planned crafts in the series:
ADM-Aeolus (Atmospheric Dynamics Mission), with a 2010 launch date, will collect data about the global wind profile to improve weather forecasting.
CryoSat-2, set to launch in late 2009, will determine variations in the thickness of the Earth’s continental ice sheets and marine ice cover to further our understanding of the relationship between ice and global warming. CryoSat-2 replaces CryoSat, which was lost at launch in 2005.
Swarm, due for launch in 2010, is a constellation of three satellites to study the dynamics of the magnetic field to gain new insights into the Earth system by studying Earth’s interior and its environment.
EarthCARE (Earth Clouds Aerosols and Radiation Explorer), lanching in 2013, is a joint European-Japanese mission that aims to improve the representation and understanding of the Earth’s radiative balance in climate and numerical weather forecast models.
The Mars feature of Google Earth 5.0 lets users see the Red Planet from the perspective of Rovers like the NASA Mars Pathfinder Rover. (Credit: NASA/Google/JPL/University of Arizona)
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Google Earth now allows you to probe the depths of Earth’s oceans as well as fly through the giant canyons or volcanoes on Mars. Google Earth 5.0 was unveiled today, with substantial upgrades for both the Earth and the Red Planet. Google worked in conjunction with NOAA and NASA to incorporate data from our undersea explorations and the spacecraft orbiting Mars. For the first time, you’ll be able to look at the two-thirds of our planet covered by the oceans, take a tour below sea level, and even look at historical imagery to see things like coastal erosion. On Mars there’s a rich conglomeration of images, including the most recent from the Mars Reconnaissance Orbiter to provide an immersive 3D view of Mars. Marine scientists say the electronic images will boost awareness and increase public support for marine conservation, while NASA says the new features in Google Mars will aid public understanding of Mars science, while also providing researchers a platform for sharing data similar to what Google Earth provides for Earth scientists.
In Google Oceans, you can click a function called Touring and you can create narrated, illustrated tours, on land or above and below the sea surface, describing and showing things like a hike or scuba excursion, or even a research cruise on a deep-diving submarine. A view of the coast of Maui, outside Lanai City, Hawaii, from the new version of Google Earth.
By choosing among 20 buttons holding archives of information, called “layers” by Google, a visitor can read logs of oceanographic expeditions, see old film clips from the heyday of Jacques-Yves Cousteau and check daily Navy maps of sea temperatures.
While only 5% of the ocean floor is mapped in detail, the replicated seas have detailed topography reflecting what is known about the abyss and continental shelves with rougher areas where little is known.
On Mars, you can enjoy a high-resolution, three-dimensional view of the Red Planet.
There is a mode that enables users to fly virtually through enormous canyons and scale huge mountains on Mars that are much larger than any found on Earth. Users also can explore the Red Planet through the eyes of the Mars rovers and other Mars missions, providing a unique perspective of the entire planet.
Clickable links allow you to learn about new discoveries and explore indexes of available Mars imagery. If you’re into working with the raw images from the Mars rovers or orbiting spacecraft, the new Mars mode also allows users to add their own 3D content to the Mars map to share with the world.
Since 2005, Google Earth has been downloaded on half a billion computers, and visitors spend one million hours a day perusing Google Earth and the related Google Maps.
A new paper published by a leading researcher says many effects of climate change are already irreversible. Susan Solomon, a leader of the International Panel on Climate Change and a scientist with National Oceanic and Atmopheric Association (NOAA) said even if carbon emissions were stopped, temperatures around the globe will remain high until at least the year 3000. And if we continue with our current carbon dioxide emissions for just a few more decades, we could see permanent “dust bowl” conditions.
Solomon defined “irreversible” as change that would remain for 1,000 years even if humans stopped adding carbon to the atmosphere immediately. As carbon dioxide emissions rise, the planet will be undergo more and more long term environmental disruptions which will persist even if and when emission are brought under control.
The report says temperatures around the globe have risen and changes in rainfall patterns have been observed in areas around the Mediterranean, southern Africa and southwestern North America. Warmer climate also is causing expansion of the ocean, and that is expected to increase with the melting of ice on Greenland and Antarctica.
A recent NASA article said observations have confirmed rising temperatures in Antarctica over the past 50 years in not only the Antarctic Peninsula, but in western Antarctica as well.
In a teleconference, Soloman said this is not just another pollution problem. “We’re used to pollution problems being something we can fix, smog, — we can cut back and things will get better later. Or haze, we think it will go away pretty quickly.”
This is true for gases like methane and nitrous oxide, but not for CO2. “People have imagined that if we stopped emitting carbon dioxide that the climate would go back to normal in 100 years or 200 years,” said Solomon. “What we’re showing here is that’s not right. It’s essentially an irreversible change that will last for more than a thousand years.”
This is because the oceans are currently soaking up a lot of the planet’s excess heat, as well as some of the carbon dioxide from the atmosphere. The carbon dioxide and heat will eventually start coming out of the ocean. And that will take place for many hundreds of years.
The scientists say that once the global thermostat once it has been turned up, its extremely difficult to turn it back down.
Solomon said sea level rise is a much slower thing to happen, that it will take a long time, but we will lock into it based on the peak level of C02 we reach this century.
So, should we just give up? Are we doomed? “It seems like this is even more reason to do something about it,” Solomon said. “When you are committing to something you can’t back out of, you need to proceed even more carefully than when it’s something you can reverse….I don’t think that the very long time scale of the persistence of these effects has been understood.”
The Compton Gamma Ray Observatory shortly after deployment by shuttle Atlantis (STS-37) on April 5th, 1991 (NASA)
[/caption]From 1991 to 2000, the Compton Gamma Ray Observatory dominated the search for the largest explosions ever observed in the cosmos: gamma-ray bursts (or GRBs). Unfortunately after nearly a decade of highly successful observations, June 4th 2000, NASA made the unpopular decision to de-orbit the observatory in response to a mechanical failure on the spacecraft (despite protests by some scientists, pointing out that the observatory could have continued operations).
To one scientist, Jim Ryan, the demise of the project he had tirelessly worked on since 1984 was a hard pill to swallow. However, in a surprise turn of events, the US Department of Energy tracked down Ryan and asked whether his research could be applied a little closer to home. In a flash of inspiration, the scientist realised spare parts left over from the Compton Gamma Ray Observatory could be used to pinpoint emissions from a potential “dirty bomb”, possibly providing security services with an early warning capability against a radioactive terrorist attack…
Although a dirty bomb has never been detonated and remain a speculative means by terrorists to cause maximum disruption to a populated area, the Department of Energy considers the threat to be very real. This is probably because a small amount of radioactive material could be used in the construction of a relatively cheap conventional bomb and plans by groups to use such weaponry have been uncovered in the past. The key power of a dirty bomb (otherwise known as a “radiological dispersal device”) isn’t the immediate health risk to a local population (apart from the obvious damage that could be caused by the conventional explosives used in the device), it is the lasting fear, panic and economic damage such a terror attack could cause. The residual radiation left over from a dirty bomb is of course a concern, but studies show that it is the psychological damage of such an attack that would have the greater effect.
So, the Department of Energy gave Dr Ryan a call to ask whether his work at the University of New Hampshire’s Space Science Center could be used to seek out radioactive devices. At the time, he was working on an instrument to be sent within the orbit of Mercury to detect low energy neutrons being emitted from the Sun. It just so happened that the neutron energy range matched that of the emission from plutonium.
“You don’t have to be an astrophysicist to see the connection,” Ryan commented on the government interest in using his techniques to search for nuclear devices on Earth.
However, during a visit to a National Guard exercise on Cape Cod, Jim Ryan was inspired by another space mission. The exercise carried out last year was to test security agent’s ability to track down dirty bombs (not nuclear weapons containing plutonium). Dirty bombs emit a different type of radiation (not the low energy neutrons emitted from a plutonium device), and Ryan realised that parts from his old and beloved Compton Gamma Ray Observatory may be resurrected to help serve national security tasks. Rather than manually scanning suspect radioactive devices with a hand-held Geiger counter, the gamma ray radiation can be detected at a safe distance and pinpointed. The problem with Geiger counters is that although they detect gamma radiation, you have to be standing right next to the radioactive source to know where it is. Using Compton Gamma Ray Observatory techniques can make the search safer and a lot more accurate.
“It lives on and does something that is useful to society as well as pure academic science,” Ryan said during a presentation to a Homeland Security conference in May. “[It is] poetic justice,” that the techniques by the spacecraft will be re-used by the modern fight against international terrorism.
Santa Ana wind-fuelled wildfires on October 13th in the San Fernando valley, north of Los Angeles. NASA's Aqua satellite captured this image (NASA)
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This morning at 5:30am, I woke up to the smell of smoke. It’s one of those horrid, gut-wrenching feelings for anyone as your mind jumps from “did I leave the oven on?” to “oh no, it’s our turn.” The latter thought is probably one that everyone living near summer-dried woodland in California thinks on waking to the smell of smoke. And in the San Fernando Valley, we’ve had one or two scares this year.
The advance of the wildfires can be very fast. A view of the Santa Barbara fire (Tynan Daniels/CNN)My wife and I live in Woodland Hills, about 20 minutes from Los Angeles, and before I moved to the US Deb warned me, “there might be a chance that we’ll get affected by a wildfire at the new house.” Coming from the UK, where the worst thing I’ve experienced was a flood (one of those car-floating floods the British countryside does so well), it was a little unnerving that I was moving to Southern California where I’d already experienced an earthquake and seen the damage caused by wildfires first-hand. It’s little wonder my family are constantly texting me asking “is everything OK?”
This time, it wasn’t “our turn” as we live on the south-west side of the valley. But late last night, hundreds of families weren’t so lucky and had to be evacuated from their homes as fires raged along the northern edge of the LA County line up to Santa Barbara…
It was a strange atmosphere in the valley today. A huge smokestack was growing about 12 miles north, and brown smoke filled the air, filtering out much of the sunlight. Walking into the garden with my coffee after the disturbed night sleep, I noticed a thin layer of soot over the patio and table. It was eerily quiet. Add this to the unseasonably warm weather we are having, there was a real sense the raging wildfire was a lot closer than it was.
Grid lock on the I-15 in San Bernardino, CA, during the October 2007 wildfires (Ian O'Neill) This is fire season after all, when the strong offshore Santa Ana winds sweep across Southern California, fanning the flames of wildfires with the dry, warm air from the desert. This is the time when everyone is a little edgy when even a hint of smoke can be smelled in the air. Should fire take hold in the dry vegitation, firefighters have to throw everything they’ve got at the area affected, preventing damage to property and loss of life.
Last month was my last experience of a particularly vicious sequence of fires (again, causing huge problems for people in the north of the valley), and it looks like we have a few more days of trouble ahead of us. Governor Arnold Schwarzenegger has issued an emergency declaration for the Sayre fire in Sylmar and as I write, mandatory evacuations have been placed on some locations north of LA, down to Orange County. There is also the threat of rolling blackouts as the blazes deprive some areas of electricity supplies. The problem is spreading across the region.
Use Google Maps to monitor the areas affected in the region »
This afternoon, although life continued as normally as it could though the unhealthy haze of smoke trapped in the valley basin, I saw two yellow firefighting aircraft landing in Van Nuys airport, before flying north to assist the thousands of brave firefighters on the ground. We can only imagine how extreme it must be over there.
NASA’s Autonomous Modular Scanner, onboard the Ikhana remotely-operated aircraft, images fires in Monterey County, CA on July 8th, 2008 (NASA/Google)So, out of interest, I decided to do some research to see if the guys on the ground were getting any help from NASA (after all, the agency has a developed Earth observatory program), surely there is an “eye in the sky” that can help co-ordinate efforts down here?
In July, when California was suffering a state-wide wildfire emergency (is it me, or has the wildfire season lasted a lot longer this year?), NASA flew a robotic Ikhana aircraft across much of the state, charting over 300 fires that had broken out. The Ikhana was using an Autonomous Modular Scanner developed at NASA’s Ames Research Center at Moffett Field to precisely measure temperature variations across the landscape from one-half degree to approximately 1,000 °F (537 °C). Areas currently burning and areas already burnt could then be identified. From this information, areas at risk could be quickly focused on, providing the firefighters with advanced warning before a fire takes hold.
“NASA’s emergency imaging gives us immediate information that we can use to manage fires, identify threats and deploy firefighting assets,” Governor Schwarzenegger said in July. “I thank NASA for providing us with this important firefighting tool.”
Whether or not the Ikhana aircraft is in the skies at the moment, it is unknown, but NASA has some other fire monitoring tricks a little higher in the sky.
The Moderate Resolution Imaging Spectroradiometer (MODIS) flies onboard NASA’s Aqua and Terra satellites as part of the NASA-centered international Earth Observing System. Both satellites orbit the Earth from pole to pole, seeing most of the globe every day. Onboard Terra, MODIS sees the Earth during the morning, while Aqua MODIS orbits the Earth in the afternoon.
True-color, photo-like imagery and false-color imagery are available within a few hours of being collected, making the system a valuable resource for organizations like the U.S. Forest Service and the international fire monitoring community, who use the images to track fires; the United States Department of Agriculture Foreign Agricultural Service, who monitors crops and growing conditions; and the United States Environmental Protection Agency and the United States Air Force Weather Agency, who track dust and ash in the atmosphere. The science community also uses the system in projects like the Aerosol Robotic Network (AERONET), which studies particles like smoke, pollution, or dust in the atmosphere.
Here’s to hoping NASA’s resources are being made available as widely as possible as LA County is now in a state of emergency. Our thoughts are with the people who have been injured, displaced and lost their homes, and to the Fire Service who are fighting day and night to bring these blazes under control.
Ozone hole during 7 October 2008 as measured by the Scanning Imaging Absorption Spectrometer for Atmospheric Cartography (SCIAMACHY) atmospheric sensor onboard ESA’s Envisat. Credits: KNMI/ESA
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Is the ozone hole was recovering? Maybe not. The protective atmospheric layer of ozone around our planet has been thinning over Antarctica for many years. New satellite data indicates the 2008 ozone hole is larger both in size and ozone loss than 2007 but is not as large as the record year of 2006. This year the area of the thinned ozone layer over the South Pole reached about 27 million square kilometers, compared to 25 million square kilometers in 2007 and a record ozone hole extension of 29 million square kilometers in 2006, which is about the size of the North American continent. Ozone is a protective atmospheric layer found about 25 kilometers in altitude that acts as a sunlight filter, shielding life on Earth from harmful ultraviolet rays. A thinner ozone layer can increase the risk of skin cancer and cataracts and harm marine life. What causes the ozone layer to change from year to year, and if CFC’s have been banned, why isn’t the ozone recovering?
The depletion of ozone is caused by extreme cold temperatures at high altitude and the presence of ozone-destructing gases in the atmosphere such as chlorine and bromine. Most of these gases originate from man-made products like chlorofluorocarbons (CFCs), which were phased out under the 1987 Montreal Protocol. But they continue to linger in the atmosphere.
Depending on the weather conditions, the size the Antarctic ozone hole varies every year. As the polar spring arrives in September or October, the combination of returning sunlight and the presence of so-called stratospheric clouds (PSCs) over the Antarctic leads to a release of highly ozone-reactive chlorine radicals present in the atmosphere that break ozone down into individual oxygen molecules. A single molecule of chlorine has the potential to break down thousands of molecules of ozone.
Chlorine activation and ozone hole extension early September 2007 and 2008. Credits: DLR
Colder temperatures in the stratosphere over Antarctica, combined with a high formation rate of PSCs caused more lingering chlorine radicals to be released, making the current hole one of the largest. 2006 saw the largest hole. A unit of measurement called a Dobson Unit describes the thickness of the ozone layer, and this year (2008) about 120 Dobson Units were observed compared to around 100 Dobson Units in 2006.
The analysis is based upon the Scanning Imaging Absorption Spectrometer for Atmospheric Cartography (SCIAMACHY) atmospheric sensor onboard ESA’s Envisat, the Global Ozone Monitoring Experiment (GOME) aboard ESA’s ERS-2 and its follow-on instrument GOME-2 aboard EUMETSAT’s MetOp.
