Finally Confirmed the Existence of Hypothetical Particle That Could Help Cool the Planet

We can fit everything we knew before today about Criegee biradicals inside the period at the end of this sentence, but from what we understand they are pretty amazing. At least, that’s the word from a team of researchers form the U. of Manchester, the U. of Bristol, and Sandia National Labs, who have just detected these invisible chemical intermediates for the first time. Apparently they can not only oxidize pollutants from combustion, cleaning up the atmosphere as they go, but they also contribute to cloud formation, helping to cool the planet.

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Criegee biradicals were first hypothesized in the 1950s by German chemist Rudolf Criegee, but at that point in time it was impossible to detect them or measure them, so it was unknown whether or not they truly existed and, if so, how fast they reacted with other atoms. Finding and measuring them was made possible by a special device rigged up by Sandia researchers at Lawrence Berkeley National Labs’ Advanced Light Source, which allowed them to discern the formation and eliminate other similar molecules that contain the same atoms but in a different structure.

What they found in doing so, we’re told, is quite promising. Criegee biradicals react more rapidly than researchers previously thought they could with aforementioned pollutants like nitrogen dioxide and sulfur dioxide, leaving behind nitrate and sulfate that lead to aerosol formation and eventually cloud formation. Ultimately, Criegee biradicals could help cool the planet.

Moreover, understanding them should lend atmospheric researchers some insight on the oxidizing capacity of the atmosphere as a whole as well as help lead to better understandings of climate and how pollution affects the air around us.

Environment Clean Generations

The Hole is Still There

The Antarctic ozone hole, which yawns wide every Southern Hemisphere spring, reached its annual peak on September 12, stretching 10.05 million square miles, the ninth largest on record. Above the South Pole, the ozone hole reached its deepest point of the season on October 9 when total ozone readings dropped to 102 Dobson units, tied for the 10th lowest in the 26-year record.

The ozone layer helps protect the planet's surface from harmful ultraviolet radiation. NOAA and NASA use balloon-borne instruments, ground instruments, and satellites to monitor the annual South Pole ozone hole, global levels of ozone in the stratosphere, and the humanmade chemicals that contribute to ozone depletion.

"The upper part of the atmosphere over the South Pole was colder than average this season and that cold air is one of the key ingredients for ozone destruction," said James Butler, director of NOAA's Global Monitoring Division in Boulder, Colo. Other key ingredients are ozone-depleting chemicals that remain in the atmosphere and ice crystals on which ozone-depleting chemical reactions take place.

"Even though it was relatively large, the size of this year's ozone hole was within the range we'd expect given the levels of manmade, ozone-depleting chemicals that continue to persist," said Paul Newman, chief atmospheric scientist at NASA's Goddard Space Flight Center.

Levels of most ozone-depleting chemicals are slowly declining due to international action, but many have long lifetimes, remaining in the atmosphere for decades. Scientists around the world are looking for evidence that the ozone layer is beginning to heal, but this year's data from Antarctica do not hint at a turnaround.

In August and September (spring in Antarctica), the sun begins rising again after several months of darkness. Circumpolar winds keep cold air trapped above the continent, and sunlight-sparked reactions involving ice clouds and humanmade chemicals begin eating away at the ozone. Most years, the conditions for ozone depletion ease by early December, and the seasonal hole closes.

Levels of most ozone-depleting chemicals in the atmosphere have been gradually declining since an international treaty to protect the ozone layer, the 1987 Montreal Protocol, was signed. That international treaty caused the phase out of ozone-depleting chemicals, then used widely in refrigeration, as solvents and in aerosol spray cans.

Environment-Clean-Generations

Global atmospheric models predict that stratospheric ozone could recover by the middle of this century, but the ozone hole in the Antarctic will likely persist one to two decades beyond that, according to the latest analysis by the World Meteorological Organization, the 2010 Ozone Assessment, with co-authors from NOAA and NASA.

Researchers do not expect a smooth, steady recovery of Antarctic ozone, because of natural ups and downs in temperatures and other factors that affect depletion, noted NOAA ESRL scientist Bryan Johnson. Johnson helped co-author a recent NOAA paper that concluded it could take another decade to begin discerning changes in the rates of ozone depletion.

Johnson is part of the NOAA team tracks ozone depletion around the globe and at the South Pole with measurements made from the ground, in the atmosphere itself and by satellite. Johnson's "ozonesonde" group has been using balloons to loft instruments 18 miles into the atmosphere for 26 years to collect detailed profiles of ozone levels from the surface up. The team also measures ozone with satellite and ground-based instruments.

This November marks the 50th anniversary of the start of total ozone column measurements by the NOAA Dobson spectrophotometer instrument at South Pole station. Ground-based ozone column measurements started nearly two decades before the yearly Antarctic ozone hole began forming, therefore helping researchers to recognize this unusual change of the ozone layer.

NASA measures ozone in the stratosphere with the Ozone Monitoring Instrument (OMI) aboard the Aura satellite. OMI continues a NASA legacy of monitoring the ozone layer from space that dates back to 1972 and the launch of the Nimbus-4 satellite.

by "environment clean generations"

Sea Levels Rising for 500 Years?

Rising sea levels in the coming centuries is perhaps one of the most catastrophic consequences of rising temperatures. Massive economic costs, social consequences and forced migrations could result from global warming. But how frightening of times are we facing? Researchers from the Niels Bohr Institute are part of a team that has calculated the long-term outlook for rising sea levels in relation to the emission of greenhouse gases and pollution of the atmosphere using climate models.

The results have been published in the scientific journal Global and Planetary Change.

"Based on the current situation we have projected changes in sea level 500 years into the future. We are not looking at what is happening with the climate, but are focusing exclusively on sea levels," explains Aslak Grinsted, a researcher at the Centre for Ice and Climate, the Niels Bohr Institute at the University of Copenhagen.

Model based on actual measurements

He has developed a model in collaboration with researchers from England and China that is based on what happens with the emission of greenhouse gases and aerosols and the pollution of the atmosphere. Their model has been adjusted backwards to the actual measurements and was then used to predict the outlook for rising sea levels.

The research group has made calculations for four scenarios: a pessimistic one, an optimistic one, and two more realistic ones.

In the pessimistic scenario, emissions continue to increase. This will mean that sea levels will rise 1.1 meters by the year 2100 and will have risen 5.5 meters by the year 2500.

Even in the most optimistic scenario, which requires extremely dramatic climate change goals, major technological advances and strong international cooperation to stop emitting greenhouse gases and polluting the atmosphere, the sea would continue to rise. By the year 2100 it will have risen by 60 cm and by the year 2500 the rise in sea level will be 1.8 meters.

For the two more realistic scenarios, calculated based on the emissions and pollution stabilizing, the results show that there will be a sea level rise of about 75 cm by the year 2100 and that by the year 2500 the sea will have risen by 2 meters.

Rising sea levels for centuries

"In the 20th century sea has risen by an average of 2mm per year, but it is accelerating and over the last decades the rise in sea level has gone approximately 70% faster. Even if we stabilize the concentrations in the atmosphere and stop emitting greenhouse gases into the atmosphere, we can see that the rise in sea level will continue to accelerate for several centuries because of the sea and ice caps long reaction time. So it would be 2-400 years before we returned to the 20th century level of a 2 mm rise per year," says Aslak Grinsted.

He points out that even though long-term calculations are subject to uncertainties, the sea will continue to rise in the coming centuries and it will most likely rise by 75 cm by the year 2100 and by the year 2500 the sea will have risen by 2 meters.

 by "environment clean generations"

Snackable Sponge Can Suck Up CO2

Sponges already clean up kitchen spills and soap scum, now they may start cleaning up the atmosphere.

A newly-developed synthetic sponge made of salt, sugar, and alcohol soaks up carbon dioxide. It's non-toxic, reusable, and carbon neutral. In a pinch, you can even make a meal of it.

Northwestern University chemists developed this special sponge, known as a metal-organic framework (MOF). Other MOFs soak up carbon dioxide too, but are usually made from crude oil and contain more toxic heavy metals than Beavis and Butthead's record collection.

 The new sponges don't pollute the environment while cleaning it up. In fact, their manufacture could reduce the amount of greenhouse gas in the air, since they contain sugar made by plants which themselves pull carbon dioxide out of the air.

“We are able to take molecules that are themselves sourced from atmospheric carbon, through photosynthesis, and use them to capture even more carbon dioxide,” said Ross Forgan, a co-author of the sponge study published in Journal of the American Chemical Society, in a press release.

“By preparing our MOFs from naturally derived ingredients, we are not only making materials that are entirely nontoxic, but we are also cutting down on the carbon dioxide emissions associated with their manufacture,” said Forgan.

The main ingredient is gamma-cyclodextrin, a type of sugar derived from corn, held together in a crystalline structure by metals, such as potassium benzoate and rubidium hydroxide, derived from salts.

Despite the intimidating names of its ingredients, the MOF carbon sponge is actually edible.  But don't sit down to a sponge lunch just yet, the carbon-hungry sponges can be cleaned and reused.

“It turns out that a fairly unexpected event occurs when you put that many sugars next to each other in an alkaline environment -- they start reacting with carbon dioxide in a process akin to carbon fixation, which is how sugars are made in the first place,” said Jeremiah J. Gassensmith, lead author of the paper, in a press release.

“The reaction leads to the carbon dioxide being tightly bound inside the crystals, but we can still recover it at a later date very simply,” Gassensmith said.

The MOF sponges suck in the carbon dioxide and converts it to carbonate. But when exposed to an atmosphere with low concentrations of carbon dioxide, the gas is released.

Unlike other methods of carbon capture, little extra energy is needed to release the carbon dioxide.

"In our material, the CO2 is converted into a solid, most likely by reacting with the sugar, but if you blow a stream of nitrogen over the material, the CO2 spontaneously pops off and will go wherever you blow it, and the material is reused and thus recyclable.

"It is thus a very, very green way of trapping CO2," Gassensmith said.

The sponges could be used to scrub emissions or the air itself. The excess carbon can then be used in other industrial processes or stored somewhere.

The sponge even lets people know when it's ready for a cleaning.

The researchers included methyl red, a common chemical pH indicator, in the sponges to let them know when the sponge has soaked up all the carbon it can. A pH shift within the sponge causes the color to change from yellow to red when it is full of carbon.

Since the MOF carbon sponges are cheap and easy to manufacture, not to mention eco-friendly, Northwestern plans to pursue commercialization opportunities.

“I think this is a remarkable demonstration of how simple chemistry can be successfully applied to relevant problems like carbon capture and sensor technology,” said Ronald A. Smaldone, a co-author of the paper.

 by "environment clean generations"

I Wanna Make My Own Spacecraft

"The surface of the Earth is the shore of the cosmic ocean. On this shore, we have learned most of what we know. Recently we have waded our way out, maybe ankle deep, and the water seems inviting."

Those were the words of Carl Sagan back in 1980 on the PBS television show "Cosmos: A Personal Voyage." More than three decades have passed since the episode first broadcast, and for most of that time space travel has remained the exclusive domain of national space programs such as NASA or the European Space Agency (ESA).

 Recently, private companies have begun to dip their toes in the cosmic ocean, too. The players range from economic titans like Richard Branson's Virgin Galactic to small, independent ventures questing after a Lunar X Prize.

What about you? Have we reached the point where regular folks can build their own homemade spacecraft? Or are we still confined to walk the shores?

What constitutes a spacecraft? By most definitions, it's a manned or unmanned vehicle designed to travel or function outside Earth's atmosphere. That's pretty good news for do-it-yourselfers with cosmic ambitions, because the minimum task boils down to sending a small device to a point approximately 62 miles (100 kilometers) above sea level. That point is also known as the Kármán line.

The border between atmosphere and space is far from set in stone -- or air. NASA and the United States Air Force, for instance, tend to identify the barrier at 50 miles (81 kilometers) [source: NASA]. If you were feeling particularly stingy, however, you could place the limits of Earth's atmosphere as high as 373 miles (600 kilometers) above sea level, where the outer limits of the thermosphere gradually terminate. Of course, this would make the International Space Station more of an upper atmosphere station, as it hangs out at roughly 220 miles (354 kilometers) above sea level.

So let's say you absolutely have to launch a small device into space as soon as possible. In order to send a payload to such a lofty altitude, you're going to want to turn to one of two propulsion methods: a balloon or a rocket.

Rockets pose a bit of a risk because, let's face it, everything from holiday fireworks to the Saturn Vs used in the Apollo missions are nothing short of controlled explosions. They depend on often dangerous and tightly controlled chemical components that combust to produce thrust. Dangers aside, the construction costs for such a spacecraft typically put the venture outside the range of the individual.

Rockets and Balloons Striving to Reach Space

In 2007, a team of British rocket enthusiasts spent 4,000 pounds (roughly 6,000 U.S. dollars) on a homemade rocket. Designed by rocketeer Richard Brown, the rocket stood 12.5 feet (3.8 meters) tall and was dubbed "Corpulent Stump." At the time, it was the largest amateur rocket ever built, but still only ascended to an altitude of roughly 1.1 miles (1.8 kilometers). That's far shy of both the Kármán line and NASA's 50-mile (81-kilometer) border.

Three years earlier, the U.S.-based Civilian Space eXploration Team (CSXT) successfully launched the first amateur rocket into space. That rocket allegedly reached an altitude of roughly 70 miles (113 kilometers) [source: AP]. While CSXT's expenses aren't publicly known, estimations run in the tens of thousands of dollars [source: Graham-Rowe]. Of course, such high costs are the reason the X Prize Foundation and likeminded organizations exist: to provide lucrative cash prizes to those who push the boundaries of independent space research.

So let's forget about building a space rocket in your shed, at least for the moment. What about balloons?

The idea itself is nothing new. NASA successfully launched the first space balloon, Echo 1A, on Aug. 12, 1960, to an altitude of 1,000 miles (1,609 kilometers). Again, if space begins at either the 62-mile (100-kilometer) or the 50-mile (81-kilometer) point, the historic flight more than qualified the balloon as a spacecraft. The 31,416 square-foot (2,918 square-meter) balloon consisted of a reflective aluminum coating over an inflated Mylar plastic sphere [source: Choi]. You can think of it as an absurdly oversized Christmas tree ornament -- one capable of reaching staggering altitudes.

Several amateur "space balloons" have made the headlines in recent years, and with good reason. For instance on Sept. 30, 2010, a father and son team out of Brooklyn, N.Y., attached a camera to a balloon and captured stunning footage of the edge of space. It's an inspiring story, certainly, but it also only reached an altitude of 19 miles (31 kilometers), short of accepted space/atmosphere borders. As such, these ambitious efforts have only reached "near-space."

So for now, space flight would seem to remain the exclusive domain of nations and private companies.

by "environment clean generations"

Deciphering The Earth, A Brief Review

n "The Hitchhiker's Guide to the Galaxy," Arthur Dent has trouble getting his mind around the Vogon Constructor Fleet's destruction of the Earth. He can't process it -- it's just too big. Arthur tries to narrow it down, but thinking of England, New York, Bogart movies and the dollar produces no reaction. Only when he considers the extinction of McDonald's hamburgers does it finally sink in.

After deciding to write about how the Earth works, we felt a little like Arthur Dent. Even though it's tiny compared to the rest of the universe, the Earth is enormous, and it's extremely complex.

But instead of collectively going out for a burger, we decided to take another approach. Rather than examining each of the Earth's parts, we'll look at what ties it all together. Just about everything on Earth happens because of the presence of the sun. 

Power and light

Compared to the rest of the universe, the Earth is very small. Our planet and eight (or maybe nine) others orbit the sun, which is only one of about 200 billion stars in our galaxy. Our galaxy, the Milky Way, is part of the universe, which includes millions of other galaxies and their stars and planets. By comparison, the Earth is microscopic.

Compared to a person, on the other hand, the Earth is enormous. It has a diameter of 7,926 miles (12,756 kilometers) at the equator, and it has a mass of about 6 x 10²⁴ kilograms. The Earth orbits the sun at a speed of about 66,638 miles per hour (29.79 kilometers per second). Don't dwell on those numbers too long, though; to a lot of people, the Earth is inconceivably, mind-bogglingly big. And it's just a fraction of the size of the sun.

From our perspective on Earth, the sun looks very small. This is because it's about 93 million miles away from us. The sun's diameter at its equator is about 100 times bigger than Earth's, and about a million Earths could fit inside the sun. The sun is inconceivably, mind-bogglingly bigger.

 

But without the sun, the Earth could not exist. In a sense, the Earth is a giant machine, full of moving parts and complex systems. All those systems need power, and that power comes from the sun.

The sun is an enormous nuclear power source -- through complex reactions, it transforms hydrogen into helium, releasing light and heat. Because of these reactions, every square meter of our planet's surface gets about 342 Watts of energy from the sun every year. This is about 1.7 x 10¹⁷ Watts total, or as much as 1.7 billion large power plants could generate [source: NASA]. You can learn about how the sun creates energy in How the Sun Works.

When this energy reaches the Earth, it provides power for a variety of reactions, cycles and systems. It drives the circulation of the atmosphere and the oceans. It makes food for plants, which many people and animals eat. Life on Earth could not exist without the sun, and the planet itself would not have developed without it.

To a casual observer, the sun's most visible contributions to life are light, heat and weather. Now we'll look at how the sun powers each of those.

A World of Spheres

People generally think of the Earth as a "blue marble" or a sphere, although it's really shaped more like a pumpkin. But scientists classify the Earth as several spheres:

• Atmosphere: the air we breathe


• Biosphere or ecosphere: the life on earth


• Geosphere: the layers of the planet itself


• Hydrosphere: all of the water, including oceans, rivers, and lakes


• Cryosphere: the ice at the poles


• Anthrosphere: the people who live on the Earth

 Night and day

Some of the sun's biggest impacts on our planet are also its most obvious. As the Earth spins on its axis, parts of the planet are in the sun while others are in the shade. In other words, the sun appears to rise and set. The parts of the world that are in daylight get warmer while the parts that are dark gradually lose the heat they absorbed during the day.

You can get a sense of how much the sun affects the Earth's temperature by standing outside on a partly cloudy day. When the sun is behind a cloud, you feel noticeably cooler than when it isn't. The surface of our planet absorbs this heat from the sun and emits it the same way that pavement continues to give off heat in the summer after the sun goes down. Our atmosphere does the same thing -- it absorbs the heat that the ground emits and sends some of it back to the Earth.

The Earth's relationship with the sun also creates seasons. The Earth's axis tips a little -- about 23.5 degrees. One hemisphere points toward the sun as the other points away. The hemisphere that points toward the sun is warmer and gets more light -- it's summer there, and in the other hemisphere it's winter. This effect is less dramatic near the equator than at the poles, since the equator receives about the same amount of sunlight all year. The poles, on the other hand, receive no sunlight at all during their winter months, which is part of the reason why they're frozen.

Most people are so used to the differences between night and day (or summer and winter) that they take them for granted. But these changes in light and temperature have an enormous impact on other systems on our planet. One is the circulation of air through our atmosphere. For example:

1. The sun shines brightly over the equator. The air gets very warm because the equator faces the sun directly and because the ozone layer is thinner there.


2. As the air warms, it begins to rise, creating a low pressure system. The higher it rises, the more the air cools. Water condenses as the air cools, creating clouds and rainfall. The air dries out as the rain falls. The result is warm, dry air, relatively high in our atmosphere.


3. Because of the lower air pressure, air rushes toward the equator from the north and south. As it warms, it rises, pushing the dry air away to the north and the south.


4. The dry air sinks as it cools, creating high-pressure areas and deserts to the north and south of the equator.

This is just one piece of how the sun circulates air around the world -- ocean currents, weather patterns and other factors also play a part. But in general air moves from high-pressure to low-pressure areas, much the way that high-pressure air rushes from the mouth of an inflated balloon when you let go. Heat also generally moves from the warmer equator to the cooler poles.

Imagine a warm drink sitting on your desk -- the air around the drink gets warmer as the drink gets colder. This happens on Earth on an enormous scale.

The Coriolis Effect, a product of the Earth's rotation, affects this system as well. It causes large weather systems, like hurricanes, to rotate. It helps create westward-running trade winds near the equator and eastward-running jet streams in the northern and southern hemispheres. These wind patterns move moisture and air from one place to another, creating weather patterns. (The Coriolis Effect works on a large scale -- it doesn't really affect the water draining from the sink like some people suppose.)

The sun gets much of the credit for creating both wind and rain. When the sun warms air in a specific location, that air rises, creating an area of low pressure. More air rushes in from surrounding areas to fill the void, creating wind. Without the sun, there wouldn't be wind. There also might not be breathable air at all. 

  

Sun and Moon

The sun has a relationship with the moon, too. The light we see when the moon shines at night is really reflected light from the sun. The relative positions of the sun and moon also create solar and lunar eclipses. This might make it seem like the moon is nothing without the sun, but it does some important jobs for the Earth. The moon regulates the Earth's orbit, and it causes the ocean tides.

Sugar and carbon

The Earth's atmosphere is mostly composed of nitrogen. Oxygen makes up just 21 percent of the air we breathe. Carbon dioxide, argon, ozone, water vapor and other gasses make up a tiny portion of it, as little as 1 percent. These gasses probably came from several processes as the Earth evolved and grew as a planet.

But some scientists believe that the Earth's atmosphere would never have contained the oxygen we need without plants. Plants (and some bacteria) release oxygen during photosynthesis, the process they use to change water and carbon dioxide into sugar they can use for food.


Photosynthesis is a complex reaction. In a lot of ways, it's similar to the way your body breaks down food into fuel that it can store. Essentially, using energy from the sun, a plant can transform carbon dioxide and water into glucose and oxygen. In chemical terms:
6CO₂ + 12H₂O + Light -> C₆H₁₂O₆ + 6O₂+ 6H₂O

In other words, while we inhale oxygen and exhale carbon dioxide, plants inhale carbon dioxide and exhale oxygen. Some scientists believe that our atmosphere had little to no oxygen before plants evolved and started releasing it.

Without the sun to feed plants (and the plants to release oxygen), we might not have breathable air. Without plants to feed us and the animals most people use for food, we'd also have nothing to eat.
Obviously, plants are important, but not just because they give us food to eat and oxygen to breathe. Plants help control the amount of carbon dioxide, a greenhouse gas, in the atmosphere. 

They protect the soil from wind and from water runoff, helping to control erosion. In addition, they release water into the air during photosynthesis. This water, along with the rest of the water on the planet, takes part in a huge cycle that the sun controls

  

The Carbon Cycle

Carbon is fundamental to life -- all organic forms of life contain it. On Earth, carbon cycles through the atmosphere and the planet itself. This cycle has two components. The geological component involves carbon-containing compounds eroding from the land, washing into the sea, entering the Earth's mantle layer and being expelled through volcanoes. The biological component involves plants' and animals' inspiration and expiration. Since carbon is a greenhouse gas, its presence affects how warm or cool the planet is. The NASA Earth Observatory has a thorough explanation of the carbon cycle.

Water and fire

The sun has a huge effect on our water. It warms the oceans around the tropics, and its absence cools the water around the poles. Because of this, ocean currents move large amounts of warm and cold water, drastically affecting the weather and climate around the world. The sun also drives the water cycle, which moves about 18,757 cubic miles (495,000 cubic kilometers) of water vapor through the atmosphere every yea.

If you've ever gotten out of a swimming pool on a hot day and realized a few minutes later that you were dry again, you have firsthand experience with evaporation. If you've seen water form on the side of a cold drink, you've seen condensation in action. These are primary components of the water cycle, also called the hydrologic cycle, which exchanges moisture between bodies of water and land masses. The water cycle is responsible for clouds and rain as well as our supply of drinking water.
Here's what happens:

1. The sun shines on the surface of oceans and lakes, exciting molecules of water. The more the sun excites the molecules, the faster they move, or evaporate.


2. The molecules rise through the atmosphere as water vapor. Plants add to this water vapor through transpiration, a byproduct of photosynthesis, which also depends on the sun. In some locations, water sublimates, or changes directly from ice to vapor.


3. All of this water vapor rises into the atmosphere. The higher it rises, the cooler it gets. The molecules of water slow down and stick together, or condense, as they cool. This forms clouds. Depending on how high and thick they are, clouds can either warm or cool the surface of the planet under them.


4. Droplets continue to combine inside the clouds. When they get big and heavy enough, they fall as precipitation. (Pollution in clouds can decrease the amount of rainfall by requiring droplets to be bigger and heavier before they can fall.)


5. Precipitation falls as rain, snow, sleet or hail, depending on the temperature and other conditions. Over land, it falls onto the ground and into rivers and lakes. Some of the water seeps into the soil, nourishing plants and joining the groundwater. Much of it flows into rivers and lakes, which eventually run into the ocean.

Without the sun to start the process of evaporation, the water cycle wouldn't exist. We wouldn't have clouds, rain or weather. The water on the planet would be stagnant. It would also be solid, since without the sun to warm it, the Earth would be entirely frozen.

The sun powers the processes that control our climate and the content of our atmosphere. Without it, we wouldn't have oxygen or liquid water on our planet. We wouldn't have weather or seasons. But the sun's immense source of power also has some drawbacks. Next, we'll look at some of phenomena that protect Earth from the power of the sun.

The Earth's Atmosphere

Some people imagine the Earth's atmosphere as a blanket of air that gets thinner and colder the higher you go. While the atmosphere does tend to get thinner, it's made of distinct regions, and some outer layers are much hotter than our planet's surface. NASA has a great description of the layers of the atmosphere with links to images of each.

Heat and wind

The sun's massive power source has two main disadvantages -- ultraviolet light and the solar wind. Ultraviolet light can cause cancer, cataracts and other health problems. The solar wind, a stream of charged, or ionized, particles that stream off of the sun, could strip away our atmosphere. Fortunately, the Earth has some natural defenses against both. Our ozone layer protects us from ultraviolet (UV) light, and our magnetic field protects us from the solar wind.

The stratosphere, the layer of atmosphere just above the one in which we live, contains a thin layer of ozone (O3). This layer wouldn't exist without the sun. Ozone is made of three atoms of oxygen. It's not a very stable molecule, but it takes a lot of power to create it. When UV light hits a molecule of oxygen (O2) of, it splits it into two atoms of oxygen (O).

When one of these atoms comes into contact with a molecule of oxygen, they combine to make ozone. The process also works in reverse -- when UV light hits ozone, it splits it into a molecule of oxygen and an atom of oxygen.

This process is called the ozone-oxygen cycle, and it converts UV light into heat, preventing it from reaching the surface of the Earth. Without the sun, the Earth wouldn't have an ozone layer -- but without the sun, the Earth also wouldn't need it.

 

Oxygen molecule + light = two atoms of oxygen. Oxygen atom + oxygen molecule = ozone molecule.

But while the sun creates the ozone layer, the Earth itself creates its defense against the solar wind. Without the Earth's magnetic field, ionized particles from the solar wind could strip the planet's atmosphere away. This magnetic field comes from deep inside the Earth's core. Interactions between the inner and outer core create the magnetic field.

The planet's inner core is made of solid iron. Surrounding the inner core is a molten outer core. These two layers are very deep within the Earth, separated from its crust by the thick mantle. The mantle is solid but malleable, like plastic, and it's the source of the magma that comes from volcanoes.

The Earth's inner core spins, much like the Earth spins on its axis. The outer core spins as well, and it spins at a different rate than the inner core. This creates a dynamo effect, or convections and currents within the core. This is what creates the Earth's magnetic field -- it's like a giant electromagnet. When the solar wind reaches the Earth, it collides with the magnetic field, or magnetosphere, rather than with the atmosphere.



The poles actually change places periodically -- about 400 times in the last 330 million years. The field weakens while the shift takes place. But computer simulations predict that the sun might come to the rescue, interacting with the atmosphere to supplement the magnetic field, while the shift is in process.
The Earth's physical composition generates its magnetic field. That composition is a product of the Earth's creation, which would not have been possible without the sun.

 Image courtesy SOHO Consortium. SOHO is a project of international cooperation between ESA and NASA.

How Do We Know?

As with evolution, the Big Bang Theory has caused some controversy. Here are a few of the reasons scientists think it's accurate:

• All of the matter in the universe is moving away from all the other matter at a very fast rate. Scientists have proven this by measuring stars' Hubble red shift, or how light waves get stretched out as they rush away from us.


• Scientists can detect and measure low-level radiation called cosmic microwave background (CMB) or primordial background radiation. This seems to be an aftereffect of the Big Bang. New analysis of the CMB suggests that the universe changed from a microscopic point to an enormous system in a fraction of a second

Planets and stars

The most prominent scientific theory about the origin of the Earth involves a spinning cloud of dust called a solar nebula. This nebula is a product of the Big Bang. Philosophers, religious scholars and scientists have lots of ideas about where the universe came from, but the most widely-held scientific theory is the Big Bang Theory. According to this theory, the universe originated in an enormous explosion.

Before the Big Bang, all of the matter and energy now in the universe was contained in a singularity. A singularity is a point with an extremely high temperature and infinite density. It's also what's found at the center of a black hole. This singularity floated in a complete vacuum until it exploded, flinging gas and energy in all directions. Imagine a bomb going off inside an egg -- matter moved in all directions at high speeds.

As the gas from the explosion cooled, various physical forces caused particles to stick together. As they continued to cool, they slowed down and became more organized, eventually growing into stars. This process took about a billion years.

About five billion years ago, some of this gas and matter became our sun. At first, it was a hot, spinning cloud of gas that also included heavier elements. As the cloud spun, it collected into a disc called a solar nebula. Our planet and others probably formed inside this disc. The center of the cloud continued to condense, eventually igniting and becoming a sun.

There's no concrete evidence for exactly how the Earth formed within this nebula. Scientists have two main theories. Both involve accretion, or the sticking together of molecules and particles. They have the same basic idea -- about 4.6 billion years ago, the Earth formed as particles collected within a giant disc of gas orbiting what would become our sun. Once the sun ignited, it blew all of the extra particles away, leaving the solar system as we know it. Our moon formed in the solar nebula as well.

At first, the Earth was very hot and volcanic. A solid crust formed as the planet cooled, and impacts from asteroids and other debris caused lots of craters. As the planet continued to cool, water filled the basins that had formed in the surface, creating oceans.

Through earthquakes, volcanic eruptions and other factors, the Earth's surface eventually reached the shape that we know today. Its mass provides the gravity that holds everything together and its surface provides a place for us to live. But the whole process would not have started without the sun.

by"environment clean generations"

Lightning Lights Up Laser

The European Southern Observatory (ESO) has its telescopes in Chile for this very reason: thunderstorms make it difficult to see the stars. But sometimes they can make for some cool photos! The above image was taken in Germany at the Allgäu Public Observatory in southwestern Bavaria where ESO was conducting a test of its new laser guide star unit.

The laser, in this case a 20-watt beam, forms an artificial star in the night sky 90 kilometers (56 miles) high in the Earth’s atmosphere. The laser guide star allows astronomers to calculate just how much of a blur effect the atmosphere is producing.

Taking time-lapse photos of the test, visual artist Martin Kornmesser of the ESO outreach department captured the approaching thunderstorm and its display of lightning. 

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Regarding Carbon Dioxide Emissions 2010 Worst Year Ever

“Worst year ever,” the Simpson's comic book guy might say about 2010's carbon dioxide emissions.

A record-setting 36.4 billion tons of carbon dioxide were added to the atmosphere in 2010. That's a 45 percent increase in the global annual release of carbon dioxide by humans since 1990, reports the European Commission's Joint Research Centre and PBL Netherlands Environmental Assessment Agency in the report "Long-term trend in global CO2 emissions."

Although many industrialized nations made cuts in the amount of carbon dioxide pollution they created, the rapid growth of India, China, Brazil and other developing nations resulted in a net increase during the two decades studied in the report.

The good news is that countries which signed on to the Kyoto Protocol seem likely to meet their reduction goal of 5.3 percent from 1990 levels. The European Union-27 and Russia decreased emissions by 7 percent and 28 percent respectively, between 1990 and 2010. Japan's emissions stayed at about the same level.

The United State's annual release of carbon dioxide increased 5 percent between 1990 and 2010.

After the global economy was shaken in 2008, emissions fell. But from 2009 to 2010 carbon dioxide made a serious comeback. Emissions increased 5.8 percent during that period, the fastest ever. Major economies, China (10 percent), India (9 percent), USA (4 percent) and the EU-27 (3 percent) led the pack in increased emissions of carbon dioxide pollution.

 

The record setting increase in emissions between 2009 and 2010 was really more of a return to normal after the economic recovery, and didn't necessarily represent a massive failure in reduction plans. For example, the report notes that the EU-27's emissions were lower in 2010 (4.4 billion tons) than in 2007 (4.6 billion tons).

On a person-by-person basis, the United States is still the world's number one carbon dioxide polluter, although China now releases more. The USA emits 18.6 tons of carbon dioxide per person, compared to China's 7.5 tons and the EU-27's 8.8 tons.

Despite trends towards renewable energy, hybrid cars and other more efficient technologies, power generation (40 percent) and road transportation (15 percent) account for the lion's share of pollution production, in both the industrialized and the developing world.

The European Commission’s report is based on data from the Emissions Database for Global Atmospheric Research as well as country by country statistics.

Carbon dioxide allows ultraviolet radiation from the sun to pass through the Earth's atmosphere. That radiation then heats the surface, producing infrared radiation. But carbon dioxide traps infrared radiation within Earth's atmosphere, and causes average global temperatures to rise.

by "environment clean generations"

NASA Will Send Probe Into Sun

Nasa is to fire a space probe directly at the Sun to answer some of the most important questions about our solar system.

A small car-sized spacecraft will plunge into the sun's atmosphere approximately four million miles from its surface, exploring a region no other spacecraft has ever visited before.

The unprecedented project, named Solar Probe Plus, is scheduled to launch by 2018.

Nasa has selected five science investigations that will unlock the Sun's biggest mysteries as the probe repeatedly passes through its atmosphere.

‘This project allows humanity's ingenuity to go where no spacecraft has ever gone before,' said Lika Guhathakurta, Solar Probe Plus program scientist at NASA Headquarters, in Washington.

'For the very first time, we'll be able to touch, taste and smell our sun.' 

As the spacecraft approaches the sun, its revolutionary carbon-composite heat shield must withstand temperatures exceeding about 1,400 degrees Celsius (2,550 degrees Fahrenheit) and blasts of intense radiation.

The spacecraft will have an up-close and personal view of the sun, enabling scientists to better understand and forecast the radiation environment for future space explorers. 

‘The experiments selected for Solar Probe Plus are specifically designed to solve two key questions of solar physics - why is the sun's outer atmosphere so much hotter than the sun's visible surface and what propels the solar wind that affects Earth and our solar system? ' said Dick Fisher, director of NASA's Heliophysics Division in Washington.

'We've been struggling with these questions for decades and this mission should finally provide those answers'

NASA invited researchers in 2009 to submit science proposals. Thirteen were reviewed by a panel of NASA and outside scientists and the five selected investigations are receiving approximately $180 million for preliminary analysis, design, development and tests. 

The Solar Wind Electrons Alphas and Protons Investigation will specifically count the most abundant particles in the solar wind - electrons, protons and helium ions - and measure their properties.

The investigation also is designed to catch some of the particles in a special cup for direct analysis. 

A telescope on board will make 3-D images of the sun's corona, or atmosphere. The experiment actually will see the solar wind and provide 3-D images of clouds and shocks as they approach and pass the spacecraft.

Another will make direct measurements of electric and magnetic fields, radio emissions, and shock waves that course through the sun's atmospheric plasma.

The experiment also serves as a giant dust detector, registering voltage signatures when specks of space dust hit the spacecraft's antenna.

Another experiment from the Southwest Research Institute in San Antonio will look at elements in the sun's atmosphere using a mas  spectrometer to weigh and sort ions in the vicinity of the spacecraft. 

 by "environment clean generations"

New Images Of UARS Satellite

An amateur astronomer has recorded images of the out-of-control US satellite as it tumbles back to Earth.

Theirry Legault, from Paris, captured the video as the satellite passed over northern France on 15 September.

The six-tonne, 20-year-old spacecraft has fallen out of orbit and is expected to crash somewhere on Earth on or around 24 September.

The US space agency says the risk to life from the Upper Atmosphere Research Satellite (UARS) is 1 in 3,200.

Mr Legault, an engineer, used a specially designed camera to record the tumbling satellite through his 14-inch telescope, posting the footage on his Astrophotography website.

UARS could land anywhere between 57 degrees north and 57 degrees south of the equator - most of the populated world.

Nasa says that most of the satellite will break or burn up before reaching Earth.

But scientists have identified 26 separate pieces that could survive the fall through the atmosphere. This debris could rain across an area 400-500km (250-310 miles) wide. 

Robust, spherical satellite components such as fuel tanks are often most likely to survive the fiery plunge to Earth, say space experts.

Nasa said scientists would only be able to make more accurate predictions about where the satellite might land two hours before it enters the Earth's atmosphere.

The 1 in 3,200 risk to public safety is higher than the 1 in 10,000 limit that Nasa aims for.

But agency officials stress that nobody has ever been hurt by objects re-entering from space.

Mark Matney, a scientist with Nasa's Orbital Debris Program Office, told Space.com that there was "always a concern". 

But, he added: "Populated areas are a small fraction of the Earth's surface. Much of the Earth's surface has either no people or very few people. We believe that the risk is very modest."

UARS is one of the biggest American satellites to make an uncontrolled re-entry in more than 30 years. However, the Skylab space station, which also made an uncontrolled plunge through the atmosphere in 1979, was about 15 times heavier than the tumbling satellite.

Experts say that a recent expansion in the Earth's atmosphere due to heating by ultraviolet radiation has been causing UARS to fall to Earth faster than expected. The expansion increases the atmospheric drag on satellites in space, hastening re-entry.

The US satellite was deployed in 1991 from the space shuttle Discovery on a mission to study the make-up of Earth's atmosphere, particularly its protective ozone layer.

Nasa has warned members of the public not to touch any pieces of the spacecraft which may survive the re-entry, urging them to contact local law enforcement authorities.

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More Like Dune Than Earth

We're been looking for planets around other stars that are as like Earth as possible, but new simulations show that habitable exoplanets may be much more like Arrakis (or Mars) than Earth.

The holy grail for any exoplanet hunter is of course finding a rocky planet about the same size as Earth orbiting about the same distance as Earth from another star that's similar to the sun. The most important criteria is usually how much energy the planet gets from its parent star: it can't be too hot or too cold, which is why planets that fall into that just right range of temperatures are said to exist in the "Goldilocks Zone," which implies that there's liquid water on the surface.

Goldilocks was a picky little brat, though, and for a planet to be warm and wet, it has to exist in a fairly small range of distances from its star. New simulations run by planetologists at NASA's Ames Research Center suggest that it might be more likely that habitable exoplanets won't be warm and wet at all: just warm, like deserts. Essentially, the simulations showed that planets without large amounts of surface and atmospheric water had a much wider Goldilocks Zone than planets with oceans and lots of rain. These desert planets would still have to have water, of course, it would just be mostly underground or in small oases instead.

So, here's why lots of water might be a bad thing: if you look at the "too hot" and "too cold" edges of the Goldilocks Zone, you start running into problems where having a lot of water makes temperature extremes much, much worse. Let's say you've got a planet that's right on the "cold" edge of habitable. If you've got a lot of water in the atmosphere, you probably have a lot of snow and ice, which is going to reflect solar energy back into space, cooling the planet further until it completely ices over. 

On the flip side, a wet planet that's on the "hot" edge of habitable will probably end up with a runaway greenhouse effect caused by all the extra water vapor in the atmosphere, eventually causing the oceans to boil away completely. Not pleasant.

If you take the water out of the equation, though, planetary climates become much more stable. Land planets absorb and emit heat much more efficiently, helping them regulate their temperatures. The upshot of all this is that a desert planet has a Goldilocks Zone that's a full three times larger than an ocean planet like Earth, implying that we're three times more likely to find habitable desert planets than habitable ocean planets. Things are looking good for the spice trade.

by "environment clean generations"