TED Conversations

This conversation is closed.

Why do people think the Earth orbits the Sun?

It's about frames of reference after all. What orbits what depends on your frame of reference.

From The Grand Design by Stephen Hawking and Leonard Mlowdinow:
"Although it is not uncommon for people to say Copernicus proved Ptolemy wrong, that is not true. As in the case of the goldfish, one can use either picture as a model of the universe. The real advantage of the Copernican system is that the mathematics is much simpler in the frame of reference in which the sun is at rest."

See: http://www.time.com/time/arts/article/0,8599,2017262,00.html

Share:
  • thumb
    Feb 22 2011: No law of gravity can explain the orbits of the planets without accepting that they all orbit around the sun. Their motions relative to us could not be explained in a universal formula that applies as equally to an apple as it does to Jupiter. Kepler tried for years to find a model that worked with the Earth at it's center, and he did a lot of good, hard work on it too. But he eventually had to accept that the sun was the center of the solar system, not the Earth. Everything moved in nice clean ellipses that way.

    But the sun occupies no privileged position. It's orbital inclination has no bearing on that of the galaxy's. In fact, the sun itself orbits around the center of the galaxy. What orbits what depends on what the mass of the respective bodies are, what their speed and direction is relative to each other, and their mass, speed and direction relative to any other nearby bodies. Regardless of perspective, the laws of gravity are the same every where. Those laws are what govern which things orbit which other things. Whatever our desires, what ever our perspective, the earth, along with all the other planets of the solar system, orbit the sun.
  • Mar 7 2011: Our views of the universe has oscillated back and forth between a helio-centric and a geocentric universe. After centuries of studying, we pretty much settled that Earth revolves around the Sun while spinning (rotating) around its own axis. Please see these POSSIBLE scheme of orbits that were proposed throughout the human civilization:
    www.stumbleupon.com/su/2jRGYC/dd.dynamicdiagrams.com/wp-content/uploads/2011/01/orrery_2006.swf

    Ptolemy's model of the universe, as well as the Catholic Church's model had poor predictive power and did not fit the new observations of stars. Luckily we are no longer looking out of the Earth but also looking outside of the Earth through satellites and telescopes.

    This is not a "reference point" issue. Some people choose to still believe that world is flat. And some probably think Earth is the center of the universe. These are people who generally consider themselves significant on a large scale, because insignificance scares them. Or maybe it's the poor access to information that is keeping them from knowing.
  • Mar 3 2011: People dont think that anymore!
    They know that the earth orbits the sun.
  • thumb
    Feb 18 2011: We accept the "fact" that the earth revolves around the sun so as not to be ostracized for being backward. It's not about what we "know" but what we fear. It's "accepted" not proven, by folks. It's easier than actual critical thought or investigation and frankly, it doesn't have any real impact on their lives. They do not, cannot fill their heads with that kind of information as it doesn't impact their ability to meet their needs. So, "Yeah, sure... the earth revolves around the sun... if you say so... now can I get that new cell phone so I can hook up with my girl friend, or not? My chances of having a secure and satisfying life have little to do with my understanding of my planet's orbit around the sun. So, whatever".