April 18, 2016

If the earth spins at 65.000 miles an hour, why when we look up at night the stars never move? ?

I’ve been thinking about this for a while…Hope someone can answer me this, cause that would be awesome!

Comments

nascarfan24388337

Ok, you know when your driving and in the distance you can see a mountain or a cloud? Do you notice how it moves slower than anything else outside the car. Well, thats how the Earth and stars work. The earth moves fast, but you dont see the stars move. Take a telescope and point it at one star. Leave it and come back in an hour, I promise you that the star will be out of the telescopes sight. Why? It moved.
So, its pretty much because stars are millions of miles away.

nofuchsia

They do move. Take a time exposure with a camera of about 20 minutes and see. Unfortunatly the little digital box cameras people have won’t do that so find yourself an old 35mm SLR with a manual shutter, a tripod, a shutter cord, and some good film. Set your f-stop to a high number (f8-f22) and hold the shutter open for 10 to 20 minutes.

sammi_stephens

one whith is for sure there are light years away you cant tell if you bring the object closer you can tell its gravity the must inmportant thing for the sun and pulls the earth around and around .

right wing extremist patriot

It doesn’t. The Earth spins at about 1000 miles an hour (at the equator), but the actual speed is irrelevant – it’s the rotational period that matters, which is just under 24 hours to complete a full rotation relative to the stars. Stand and watch the stars for a minute, and they’ll only have moved a quarter of a degree, less even than the hour hand of a clock. But take a long photograph of the stars and you can see clearly that they do move across the sky (relative to a ground-based observer). This – http://space.newscientist.com/data/images/ns/cms/dn11672/dn11672-1_341.jpg – is a long exposure of the night sky, showing the stars’ positions having rotated about the Earth’s axis over about an hour.

If you’re going on about why the stars don’t move because of the Earth’s movement around the sun (which is about 67,000 mph), that’s because they’re so far away, billions or trillions of miles, that it makes little discernible difference to their positions. However, the closest stars do shift their positions slightly over the course of six months (from one side of Earth’s orbit to the other, a distance of about 186 million miles). This technique is used to calculate how far away some stars are.

rgtheisen2003

The earth spins through 360degs in ~24hr
at the equator the lateral speed is then ~1000 miles per hour.
The earth also moves along its about at ~20 miles/sec (which is ~70000 mph)
Try watching the sky for a night – the only star that doesn’t move is the pole star because its above the north pole.

Go out and spot the Big Dipper early in the evening and then go out later and see where it is.

Some stars cannot be seen in summer because they are behind the sun – but once we move around our orbit those stars start to be seen at night.

take a look at:
http://cseligman.com/text/sky/skymotion.htm

http://inkido.indiana.edu/a100/celestialsphere7.html

(I can find more links if they don;t help…)

proud walker3917

There is an alternative answer to your question; if indeed you are referring to the orbit of the earth around the sun (at 95,000 km/hr).
The diameter of the orbit is quite large: about 240 million kilometers.

However; during the year, the stars do not seem to move, relative to each other (ie, they stay in the same position). As in other answers, this is because they are very very far away, the closest being over 15 million million kilometers away; so the angular difference of the direction to a star is very small. However, it is still measurable, with a fine instrument, and on close examination, the position of stars can be seen to shift slightly against the background of more distant stars over six months, as the earth orbits the sun. This shift is called the parallax difference; and can be used to calculate the distance to the closest stars.

Leave a Reply

Your email address will not be published. Required fields are marked *

Note: By filling this form and submitting your commen, you acknowledge, agree and comply with our terms of service. In addition you acknowledge that you are willingly sharing your email address with AiOWikis and you might receive notification emails from AiOWikis for comment notifications. AiOWiksi guarantees that your email address WILL NOT be used for advertisement or email marketting purposes.

This site uses Akismet to reduce spam. Learn how your comment data is processed.