Why does the Sun's apparent path through the sky change throughout the year?
I do not know anything about astronmy; but, I am curious about the sunset. Sitting on the porch in the late afternoon when the sun is going down, it appears to set in different locations. I see large changes over night, but it appears to be on top of my hill over the road then a few weeks later it appears to be in the middle of the field. Why? Is the sun moving or are we the ones moving?
We are the ones moving. What you see each day when you look at the Sun moving across the sky is the effect of the Earth rotating on its axis. Because the Earth spins on its axis, it looks like the Sun is moving across the sky.
But there's another effect at work that makes the Sun's apparent path different each day. The Earth is also revolving around the Sun, so each day of the year, the Earth is at a different point in its orbit. So because the Earth is facing the Sun at a different angle each day, the "path" the Sun makes in the sky will be different each day of the year.
In fact, the different paths that the Sun makes is what causes the seasons.
This is illustrated here.
Get More 'Curious?' with Our New PODCAST:
- Podcast? Subscribe? Tell me about the Ask an Astronomer Podcast
- Subscribe to our Podcast | Listen to our current Episode
- Cool! But I can't now. Send me a quick reminder now for later.
- What causes seasons?
- Why doesn't the length of each day change much around the solstices?
- Why do the size and brightness of the full moon change?
- How is the time of sunrise calculated?
- How does the position of Moonrise and Moonset change?
- How much can the location of sunset differ from due West?
How to ask a question:
If you have a follow-up question concerning the above subject, submit it here. If you have a question about another area of astronomy, find the topic you're interested in from the archive on our site menu, or go here for help.
This page has been accessed 47958 times since October 4, 2002.
Last modified: November 6, 2002 11:14:02 AM
Ask an Astronomer is hosted by the Astronomy Department at Cornell University and is produced with PHP and MySQL.
Warning: Your browser is misbehaving! This page might look ugly. (Details)