quick question. plz help

[bast]

if heliocentrism has been proven, why do we still use some geocentric models to explain/describe/plot things today?

 

[MeteorWayne]

Well, because we live here, and our view into space is geocentric, for one.<br /><br />For another, quite a number of things orbit the earth, so they are geocentric by definition. <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[weeman]

Heliocentric applies to the physical layout of our Solar System. Geocentric applies to our observable Universe. Earth is essentially at the center of its own observable Universe. The observable Universe is how we actually see the Universe, it differs from the definition, material Universe. <br /><br />If you traveled 5 billion lightyears away to another planet, that planet would be geocentric to its own observable Universe. <div class="Discussion_UserSignature"> <p> </p><p><strong><font color="#ff0000">Techies: We do it in the dark. </font></strong></p><p><font color="#0000ff"><strong>"Put your hand on a stove for a minute and it seems like an hour. Sit with that special girl for an hour and it seems like a minute. That's relativity.</strong><strong>" -Albert Einstein </strong></font></p> </div>

 

[CalliArcale]

<blockquote><font class="small">In reply to:</font><hr /><p>if heliocentrism has been proven, why do we still use some geocentric models to explain/describe/plot things today?<p><hr /></p></p></blockquote><br /><br />It all depends on what you're trying to do. If you want to calculate the best route to the Moon, a geocentric model is all you need. If you want to work out your trajectory for rendezvousing your spacecraft with the ISS, again, a geocentric model is sufficient, and a lot simpler, than a heliocentric one.<br /><br />But if you're trying to predict where Jupiter will be in the sky in ten years time, the heliocentric model will be much simpler. (In theory, all frames of reference are valid, so you could theoretically work it out in a geocentric model, but the math would drive you insane.) And if you want to work out the trajectory to get your space probe to Saturn, the heliocentric model is the way to go, although if you're going to orbit Saturn once you arrive, you may want to use a third model for planning that phase of the mission: call it a "kronocentric" model, after the Greek name for Saturn. Indeed, that's precisely what the Cassini team has done, although they do retain the heliocentric model for working out when there will be occultation events involving the Sun, Earth, or some other planet. <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[search]

LINK<br />Modern use of geocentric and heliocentric<br />In modern calculations, the origin and orientation of a coordinate system often have to be selected. For practical reasons, systems with their origin in the mass, solar mass or in the center of mass of solar system are frequently selected. The adjectives may be used in this context. However, such selection of coordinates has no philosophical or physical implications.<br />Fred Hoyle wrote:<br />The relation of the two pictures [geocentricity and heliocentricity] is reduced to a mere coordinate transformation and it is the main tenet of the Einstein's theory that any two ways of looking at the world which are related to each other by a coordinate transformation are entirely equivalent from a physical point of view. (Hoyle, 1973, p. 78)

 

[alokmohan]

Frame of refeence is the main thing,priciple of eqivalence.