What is the human body and the Earth, the Sun, the Universe made of? What if the history of the universe were squeezed into the period of one year? What are the coldest and the hottest objects in the universe? What is the electromagnetic spectrum? What is a planet? What is a dwarf planet? Why do the planets orbit the Sun? Donate with Crypto. Also shown, is the location of the Sun in the big picture view of our Galaxy.
It is interesting to note that recent observations by astronomers suggest that the Milky Way is in fact a "barred spiral galaxy", not just a "spiral galaxy". This means that rather than a simple spherical bulge of gas and stars at its center, it has instead a "bar of stars" crossing the central bulge.
It might look something like the image shown below of the barred spiral galaxy known as NGC But we still rotate around the center just the same! A site for ages 14 and up. If we look at a star located relatively close to us in the summer and look at it again in the winter, its apparent position in the sky changes because we are at different points in our orbit.
We see the star from different vantage points. With a bit of simple calculation, using parallax we can also figure out the distance to that star.
Earth's spin is constant, but the speed depends on what latitude you are located at. Here's an example. The circumference distance around the largest part of the Earth is roughly 24, miles 40, kilometers , according to NASA.
This area is also called the equator. If you estimate that a day is 24 hours long, you divide the circumference by the length of the day. Related: Check out some stunning images of Earth from space.
You won't be moving quite as fast at other latitudes, however. If we move halfway up the globe to 45 degrees in latitude either north or south , you calculate the speed by using the cosine a trigonometric function of the latitude. A good scientific calculator should have a cosine function available if you don't know how to calculate it. The cosine of 45 is 0. That speed decreases more as you go farther north or south. By the time you get to the North or South poles, your spin is very slow indeed — it takes an entire day to spin in place.
Space agencies love to take advantage of Earth's spin. If they're sending humans to the International Space Station, for example, the preferred location to do so is close to the equator. That's why cargo missions to the International Space Station, for example, launch from Florida.
By doing so and launching in the same direction as Earth's spin, rockets get a speed boost to help them fly into space. Earth's spin, of course, is not the only motion we have in space. We can calculate that with basic geometry. First, we have to figure out how far Earth travels. Earth takes about days to orbit the sun. The orbit is an ellipse, but to make the math simpler, let's say it's a circle.
So, Earth's orbit is the circumference of a circle. The distance from Earth to the sun — called an astronomical unit — is 92,, miles ,, kilometers , according to the International Astronomers Union. That is the radius r. So in one year, Earth travels about million miles million km.
So, Earth travels about 1.
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