Do you know where you are? how fast you are going, and in what direction?
Think before you answer. You’re moving many ways at once. Earth spins on its axis, making one rotation each day. It orbits the sun, making one revolution each year. It moves with the sun as our galaxy it self rushing way from others as the universe expands.
Where are you? only means something if you have a standard reference point and a way of nothing from it. People understood this idea as early as the stone age. Saying that a mammoth was a grazing over yonder” didn’t convey useful information saying that the animals was “100 paces north of the big rock” could mean a week of dinner for tribe.
There were no compasses until 1,000 years ago, But early human did have their old style of knowing which direction they are, In some old style or let me say languages, east it meant toward the sunrise, west”towards the evening” North, might mean towards the sea or south towards the mountains. Depending where they lived. Around 4,000 years ago, mathematicians in southeast Asia first divided the circle into 360 equal degrees. By around AD 100 THE Greeks were applying that idea to the whole planet. Every spot on Earth could have an address expressed in latitude and longitude.
Do we have standard reference point to mark those locations? Of course we do, That’s the clock and calendar.
In those system,Earth or the sun is the standard reference point. But we are not at the center of the universe. But the most purposes, the old reference points still serve just fine. anyway, the center of the galaxy is about 25,000 light years away in the constellation Sagittarius.
Read more: http://scienceray.com/astronomy/where-we-are-are-we-there-yet/#ixzz1BoXcvlnr
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