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By SciberSpace (as opposed to Cyberspace) we mean, partially, the real space! Most people think that the space between the sun and the planets is empty (or a vacuum). That's not quite right though, there is a lot happening in space . Most of us aren't aware of this in our daily lives (unless you live at high latitudes) because we don't have instruments onboard a satellite making measurements. If we did, we could spend a good chunk of our lives trying to understand what is happening in space. So what is going on in space, and what does the latitude of where you live have to do with it? Here is a brief, low key, and not too technical answer.

You know very well that as one climbs to higher altitudes (NOT latitudes!) the air gets thinner. What that means is that the number of air molecules in a given volume (say a cubic inch) decreases as you go higher above the ground. That's why, for example, people who climb very high mountains need to take oxygen with them. Although the atmosphere keeps getting thinner with altitude it doesn't quite disappear. So even if you are thousands of kilometers above the earth's surface there are still some atoms and molecules buzzing around. Because of exposure to sun's ultraviolet radiation, however, many of these atoms are ionized (meaning that at least one of their electrons has been stripped away). So the gas up there is electrically charged and can carry a current just like a piece of copper wire. An electrically charged gas has its own name, called plasma, because it behaves quite differently from a regular gas. While we are discussing nomenclature let us become familiar with another. The magnetosphere is the region of space, around the earth, starting from a couple of hundreds of kilometers above its surface and extending thousands or even millions of kilometers into space. Why not continue to call this region the atmosphere? Because magnetosphere behaves quite differently from the atmosphere.

So far we have talked about the earth's atmosphere and how it becomes the magnetosphere as we go far above the earth. Now let's look at the sun and its atmosphere which is also ionized because of the high temperature of the sun. For reasons which are not fully understood, the sun's atmosphere doesn't just sit there, but it is accelerated to very high velocities (about 400 kilometers per second!) and ejected away from the sun. This plasma which consists mainly of electrons and protons is called the solar wind. It takes a parcel of solar wind about 4 days to get from the sun to the earth (it would take you over hundred years to cover the same distance moving at 100 miles per hour!!). Once the solar wind reaches the earth it interacts with the magnetosphere and causes a variety of phenomena among them the aurora borealis (or the northern lights).

Aurora borealis is the most impressive manifestation of the interaction between the solar wind and the magnetosphere. Here are some pictures:

The top picture is taken from the ground showing the aurora in the sky. The bottom picture is from an imaging instrument (built by L. A. Frank) onboard a NASA satellite called DE-1. This picture shows several things. The green line is an outline of the continents (mostly North America and the Arctic). You can also see the day and night sides of the earth. The bright oval light in the night side is the aurora as seen from space! As you can see the auroral oval is confined to high latitudes. So if you live in the high latitude regions of the earth you can look up into the sky and see a magnificent light show due to phenomena occurring in space! What causes the aurora? The short answer is the high energy electrons bombarding the atoms and molecules in the atmosphere causing them to emit light.

The bottom line of all of this is that the atmospheres of the earth and the sun are connected. This connection has important implications for all of us. For example, the earth's climate is influenced by this interaction. Also, the magnetosphere is full of high energy particles which can affect the operations of communications, military, and weather satellites.

Over the years, many satellites have been launched to explore various regions of space and to understand the nature of the processes going on. Data obtained from these satellites have been analyzed and put into a theoretical frame work. Although much has been learned about space, not all the questions have been answered and the process of discovery and understanding is still going on. Some members of SciberNet have done computer simulations to help along this exciting venture. SciberNet has been contracted by NASA and the National Science Foundation to perform computer modeling and simulations and to compare the results with the measurements made by various spacecraft.

If you are interested in more details about space check out our educational site at UCSD by clicking the ISPEC button below:

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