How do Scientists navigate through space?

Question

say they wanted to go to the moon or mars

do they focus on the light reflecting from it?

Answer 1

Their pathway is planned out far ahead of time. If you try to travel a great distance in space, the shortest path is never the most energy-efficient path. When they launch from earth, their path is aimed away from the object, but during the journey, gravity curves it to the proper direction. Further, the Moon, Mars, and other planets and moons are all moving. So if you shoot where they are, you will definitely miss them.

So someone who is flying to the Moon would not point their spacecraft right at the moon. Instead, they would aim somewhat near it, and their path would slowly curve until it is pointing just near the moon (perhaps pointing at the moon for part of the time). It wouldn't point right at the moon on arrival, because it would want to establish an orbit around the planet.

In the case of Mars, there's even more to consider. The Earth will curve the craft's path for a while and then progressively affect it less as it gets away, and then the sun will affect it's path. The spacecraft has to predict where Mars will be when it arrives in Mars' path. In fact, light doesn't travel instantly between Mars and a spacecraft, so if they are far away, where they see Mars at will actually be significantly off from where Mars is truly located.

Also, Mars is sometimes closer to earth and sometimes far away. Earth and Mars rotate the Sun at different speeds, so all missions would be planned to reach Mars when it is close, stay there until Earth and Mars are again close, and then travel back. It would be a lot harder to try landing for a short while and then returning, as Earth could be at the other side of the Sun relative to Mars by the time the spacecraft could get to it.

So the scientists don't actually rely on direct aiming. They use math and science to measure and predict everything that is going to happen well before it has a chance to happen.

They do use the visible light coming from objects to study where they are, but they also use many different kinds of information that come from them to study them. Even this requires calculations though, as nothing that is very far away is exactly where we see it at because light requires time to travel the distance between. Failing to compensate for that would guarantee failed voyages.

Answer 2

To figure out the course to take to the moon or mars, they watch the light reflected and determine the orbit of the body. Then to actually send a space craft there, they launch it into an orbit of Earth and the gravity "slings" it into the direction they calculated. The space craft and body will eventually meet up if everything was calculated correctly. But, it takes a lot of math because you are predicting where to meet the planet in the future.

Answer 3

The science pertaining to the motions of objects in space is called celestial mechanics. The specific part of celestial mechanics that relates to spaceship navigation is the determination of transfer orbits, including the changes of velocity needed for entering or leaving a transfer orbit.

There are two basic kinds of transfer orbit.

Elliptical.

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Hyperbolic.

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Suppose you discover a new asteroid with your telescope. You'd like to send a rocket out to intercept it, but before you can do that, you must figure out what the asteroid's orbit is.

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Read my articles, and they'll teach you how to do the math for yourself.

Answer 4

Well, the scientists don't really go into space, they leave that job for others who are willing to take their lives in their own hands!  And I started to say that they are too smart to actually go!  However, I think they want to learn from all the coming and going, however, they just don't want to do it themselves!  But for the sake of argument, lets say that they actually did go, nah, they wouldn't use any type of "light reflection method", they would use the methods that are normally used here on Earth.  

Right now that's still the space ships that are sent up by chemical reactions done with the hydrogen/oxygen (fuels) reactions that would require a spark to start.  The thrust must still be more than the weight of the rockets (and all it's cargo) being sent up!  Right now, there's still no other way!

Answer 5

On earth, people navigate terrestrially by the stars.

In space, NASA is able to make highly accurate interplanetary navigation measurements using "Quasars," (which is a radio-wave transmitting distant galaxy). These Quasars allowed NASA to do the pinpoint navigation to accurately pilot the Apollo command modules from the earth to the moon, and to land the many orbiters and landers on Mars and other planets.

Such Quasars could also be used for interstellar navigation and intergalactic navigation. At this level, we would then need to account for the expansion of the universe, as these intergalactic distances measured in light-years are at an entirely different scale.

BTW- These days many of the space shuttle astronauts and cosmonauts on the International Space Station are "scientists" and not just pilots unlike one of the people below speculated.

Answer 6

Well, if we wanted to go there, we'd have to aim for not where it is, but where's it's going to be by the time we got that far.  Fortunately, we know the positions and movements of the planets and stars very well, and can predict where they will be for a long time ahead.