Thursday, January 10, 2013

movement in space

 How do you think the radio? if you see that, you will know the Earth more.

 today I will talk about the Earth of the movement in space.
Three facts about the earth's motions are of vital consequence in the princeples of the earth science: first, that the earth turns on an axis, a motion always called ratation; second ., the axis of ratation is inclinned at a constant angle with respect to the plane of the earth's orbit, or plane of the ecliptic; third, that the orientation of the earth's axis in space with respect to the stars holds nearly constant.
   Earth's rotation is the rotation of the solid Earth around its own axis. The Earth rotates towards the east. As viewed from the North Star Polaris, the Earth turns counter-clockwise.
The North Pole, also known as the Geographic North Pole or Terrestrial North Pole is the point in the Northern Hemisphere where the Earth's axis of rotation meets its surface. This is a different point than the Earth's North Magnetic Pole. The South Pole is the other point where the Earth's axis of rotation intersects its surface, in Antarctica.
The Earth rotates once in about 24 hours from the point of view of the sun and once every 23 hours 56 minutes and 4 seconds from the point of view of the stars (see below). Earth's rotation is slowing slightly with time; thus, a day was shorter in the past. This is due to the tidal effects the Moon has on Earth's rotation. Atomic clocks show that a modern day is longer by about 17 milliseconds than a century ago, slowly increasing the rate at which UTC is adjusted by leap second

In astronomy, the Earth's orbit is the motion of the Earth around the Sun, from an average distance of approximately 150 million kilometers away. A complete orbit of the earth around the Sun occurs every 365.256363 mean solar days (1 sidereal year). This motion gives an apparent movement of the Sun with respect to the stars at a rate of about 1°/day (or a Sun or Moon diameter every 12 hours) eastward, as seen from Earth. On average it takes 24 hours—a solar day—for Earth to complete a full rotation about its axis relative to the Sun so that the Sun returns to the meridian. The orbital speed of the Earth around the Sun averages about 30 km/s (108,000 km/h), which is fast enough to cover the planet's diameter (about 12,700 km) in seven minutes, and the distance to the Moon of 384,000 km in four hours.File:Seasons1.svg
 So this blog is difficult to write.I don't know the movement of the earth very well. But I want to know how can the earth move in the sapce .
 The movement of the earth creat the time and the season,so we can see the flower or the snow by diffierent seasons,and we can live by death and bron. I think is magical.
 











 

2 comments:

  1. Question1: Why does the earth rotate?

    Question2: Does the earth turn around the always same orbit?

    Question3 : Why does the earth lean?

    Comment: you put good movie on the blog of this week. It make your blog interesting.

    Suggestion for improvement: You need not make [rotation] to black. It is hard to see it.

    ReplyDelete
    Replies
    1. Answer1: I think there is a huge gravitation between the sun and the earth to make the earth ratate.

      Answer2: I don't think so. the sun is changing anytime,and the orbit will be changed.

      Answer3: I thonk it is beacause the earth is not a regular spheriod, so it should be lean for hold the whole earth and keep the rotate around the sun.

      thank you for your comment.

      Delete