Posts Tagged ‘low earth orbit’

Traveling from the surface of the Earth to surface of the Moon in 5 steps.

1. Launch from the Earth’s surface to reach Low Earth Orbit.

The first step on any ambitious adventure is typically the hardest. Step 1 is no exception, and is by far the hardest step. The rocket, fuel, and payload makes up the three major components. On the launch pad, the fuel can take up 90% of the total weight, leaving just 10% for the rocket and payload. That is the cost of accelerating to 5 miles per second, and the reason rockets are so big, when the payload can be as small as a few people. At that speed, the rocket will be less than half its weight, or half its mass, and circling the Earth. In preparation for step two, the rocket gets rid of the parts of itself that brought it here.

2. Launch from Low Earth Orbit to High Earth Orbit.

This step requires the rocket to accelerate again to go even higher, much higher than in the previous step. However, having less than half the mass, there is less to carry. Plus, the higher you go, the weaker the Earth’s gravitational pull becomes, making the job easier.

3. Launch from High Earth Orbit to Transfer Orbit.

Three items are considered in determining the speed for this journey, in chronological order: Earth; Sun; Moon. The speed must be high enough to leave Earth’s gravity completely, with some speed leftover. Then, the long distance to the moon, is actually calculated as an orbit around the Sun. That is because the Sun’s gravity overpowers the gravity of the Earth and Moon.

The last speed consideration is the Moon. Fuel is expensive and heavy, the less you take the better. But the Moon is much smaller than the Earth, so its gravity is much weaker. Therefore, you need fly just slow enough to allow the Moon to catch you in its gravity. That’s why it takes three days to travel to the moon. Travel any faster, the rocket will need extra fuel to slow down. No brakes in space.

4. Launch from Transfer Orbit to Moon Orbit.

Once you are close to the Moon, your orbit around the Sun becomes your orbit around the Moon. Gravity’s pull rises as you approach the moon, so you speed up a little bit.

5. Launch from Low Moon Orbit to the Moon’s surface.

Now to land on the Moon. You need to slow down, or speed up in the opposite direction of your orbit. That is why even this step is still a ‘Launch.’ Once complete, you should be hanging somewhere high above the Moon’s surface, where the rocket slowly and safely descends and lands.

Author: Henry Maier
Article Source: EzineArticles.com
Provided by: Digital Camera Times

Outer Space is comprised of the relatively empty regions of the universe out side the atmospheres of the celestial bodies (for instance, Earth, or the other planets in our solar system). Outer space is used to distinguish from airspace and terrestrial locations, it is not completely empty but contains low density particles as well as dark energy and dark matter.

Space is the closest form to a perfect vacuum that has been found. It has no friction, which allows all of the celestial objects within it to move along at whichever gravitational trajectory it is a part of.

The Celestial objects keep their atmospheres by adhering to their gravitational attraction. Every gravitational field has a different density. For instant, the Earth’s atmospheric gas simply decreases with distance from the object. The Earth’s atmospheric pressure drops to about 1 Pa (10-3 Torr) at 100 km of altitude, which is a common definition of boundary in the outer space. The observable universe is filled with photons which are the cosmic background radiation which has an equally correspondingly number of neutrinos.

The atmospheric density within outer space produces drag on satellites. Most artificial satellites stay in low Earth orbit to deal with this drag, and fire their engines every few days to maintain orbit. Planets are too massive to be affected by the drag of the Solar System.

A human exposed to the vacuum of space would not die from exposure, but would rather quickly asphyxiate due to the intense pressure and lack of air in outer space. Once the deoxygenated blood reached the brain, death would quickly follow. Cold or oxygen rich atmospheres can survive at as long as the oxygen density is similar to that of a standard-sea level atmosphere.

Author: Alexander Sutton
Article Source: EzineArticles.com
Provided by: Hybrid and Electric Cars

Space travel is a tricky subject, although technology on Earth is developing at tremendous speeds the same cannot really be said for space travel. If we cast our minds back over five decades ago you will remember that the mission to the moon captured every persons imagination. But not much has really been done since then.

NASA have for the last few years been developing a shuttle called Ares for the new constellation program. The basic purpose of the program is to actually gain much more experience in humans and crafts spending time away from Earth and developing technologies to go further into outer space.

Similar to the Apollo program the spacecraft will first fly a low Earth orbit, NASA has been working to retire its current shuttle fleet and begin flying the Ares program by 2015. It is rumored that a manned mission to Mars will not be until after 2030, but before that astronauts would instead visit a close asteroid.

Personally I think this is moving much to slow, by the time NASA attempts to visit Mars over 100 years would have passed since visiting the moon. I mean space exploration holds the key to life and the key to cure illnesses. By exploring space we get a lot more intelligent.

But will the Ares and constellation program be the future of any kind of space travel? Well it could certainly be, I mean millions of dollars is being invested into it and we all know that the Apollo program had had its day. They need to make a shuttle that is a lot faster. Mars is the next step, but what after Mars? Where do we go from there on? Its very hard to contemplate, but with the current shuttles there is no way that they would be able to go beyond the distance of Mars.

As well as safety most of the effort should be pushed towards actually making the shuttles faster, for true space exploration, something needs to be created to travel near to the speed of light. If this occurs then we are not only limited to just exploring our galaxy but can explore them all. I mean Earth is only going to last a certain amount of years, before the atmosphere changes, so humans need to find another way to survive. Whatever develops I am certain that it will definitely be something of great public interest.

Author: Musa Aykac
Article Source: EzineArticles.com
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