There is no definite boundary between the atmosphere and outer space. It slowly becomes thinner and fades into space. Three quarters of the atmosphere's mass is within 11 km of the planetary surface.
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The boundary of the solar system is hard to define precisely, but it is generally considered to be where the influence of the Sun's gravity gives way to the influence of interstellar space. This region is known as the heliopause, located roughly 120 times the distance from the Earth to the Sun. Beyond the heliopause lies the vast expanse of interstellar space.
Pluto is often thought to be at the edge of the Solar System. Its orbit takes it an average distance of 3,700 million miles from the Sun. This is about a million times the width of the Atlantic Ocean between Europe and the United States. However, some comets are thought to travel halfway to the nearest star- a distance of about two light years. That would make the Solar System about four light years across, which is nearly 25 trillion miles.
The Earth's atmosphere stretches from the ground to about 300 miles up, although it is only breathable up to about 30,000 feet (6 miles). The actual atmosphere extends hundreds of miles more into space (the exosphere), but becomes so thin that it is essentially non-existent. For example, the ISS (International Space Station) orbits within the thermosphere, where the atmospheric friction is less than a millionth of what it is on the surface.
We think of the atmosphere as a big ocean of air around us, but the air around us is very thin relative to the size of the earth. The "thickness" of the atmosphere or the distance between the earth's surface and the "top" of the atmosphere is not exactly measurable. With increasing altitude the atmosphere fades slowly away into space. Therefore it is not easy to tell exactly how high the atmosphere rally is. Perhaps 50 kilometers.
The answer is: it depends. NASA claims space starts at 50 miles (80 km), however the Federation Internationale Aeronautique says its at 62 km, which is the altitude reached by Virgin Galactic's SpaceShipOne spacecraft which won the X-Prize to send the first private citizen into space on a private launcher. These are merely legal definitions, however, and not scientific ones.
For instance, at 50 miles, a tenuously thin layer of atmosphere extends up to 300 miles called the thermosphere, and there is debate whether to call this part of the atmosphere or part of the ionosphere or just a sorta thick area of space.
Scientifically speaking the edge of the atmosphere varies according to a number of factors, but all relate to the temperature of the atmosphere, especially that of the upper atmosphere, which is heated by sunlight, but also by the solar wind and solar magnetosphere interacting with the Earth's magnetic field and Van Allen belts to perform a sort of slow microwave roast of the upper atmosphere.
Thus, during Solar Maximum, the uppermost atmosphere (the thermosphere) is hotter than normal and is puffed up, expanded outward, due to this heating. This can increase the drag on satellites and cause them to fall out of orbit.
We are currently in a deep solar minimum of few to no sunspots, little solar wind or magnetic interactions, so the upper atmosphere has cooled significantly and as a result it has contracted downward to a record low altitude.
However the uppermost atmosphere is VERY thin compared to sea level. The thermosphere is so thin that satellites can orbit earth within it at more than 17,000 mph for at least a few months typically.
Atmospheric pressure decreases with altitude because, like water pressure in the deep ocean, this is a function of all the air mass piled on top of it. The higher you go, the less air mass above you, so less air pressure.
The peak of Mount Everest (29,035 ft above sea level) is the highest that men have climbed and its peak is in what is called the 'death zone' which has insufficient oxygen for human beings to continue living for more than a short period of time. This is why so many climbers either carry oxygen tanks with them or they spend little time at the peak to avoid significant brain damage. As far as human beings are concerned this is the top of the useful atmosphere.
There's alot of debate on to where the atmosphere ends, but theres no real fact to where it ends.
Extra debris was swept out away from our solar system by the sun's radiation and solar wind towards the end of the formation of our solar system.
In 2012 the solar system will be exactly the same. Because 2012 is just another year there's no such thing as the end of the world
No. There is one star in our solar system, and no other solar systems within it.
There are no exoplanets in our solar system. By definition, an exoplanet is a planet that is not in our solar system.
Our Solar System