what are those lines that appear on the map that make the ISS look like its going up and down?

Question

can someone explain how that works?

but i still dont get why the ISS would go up and down. last night was over north america and in the morning was over south america

Answer 1

I'm going to assume that you're talking about the blue lines in the map at the URL I included in the Sources field. I'll give it a shot.

The ISS is orbiting the Earth, which means it's going around it in a circle. But here's the thing -- the circle isn't parallel with the Equator, it's actually TILTED with respect to the poles. Sometimes the ISS is closer to the North Pole, sometimes closer to the South Pole, but it's still going in a circle around the Earth.

Maybe this can help you visualize what's going on. Hold your left hand out in front of you and make a fist -- that's the Earth. Now, stick out your right index finger -- that's the ISS -- and move it in a circle around your fist -- a circle that's "flat," meaning parallel to the table or floor. If the ISS was making an orbit like that, the blue lines on the Web site in the URL would be flat across the map of the Earth.

Now, take your index finger (the ISS, remember) and make a different circle, but this time one that goes up and down -- like a wheel rolling away from you. That would be an orbit around the poles -- and the blue lines would be vertical on the Web site.

Now, keep your left hand in the same spot but this time, draw the orbit with your right hand so that the circle is tilted at about a 45 degree angle -- so sometimes your right finger is over your knuckles and sometimes it's under the base of your thumb.

If you were to draw out that tilted orbit on a flat surface, it would have roughly the same wave shape as the blue lines on the tracking Web site. That shape is called a "sine wave," and it is what you get when you map a circle onto a flat surface.

Now, why are there three blue curves all offset slightly? That's because the Earth is rotating under the ISS. So in one orbit it passes over North America on its way around the Earth, then in another orbit it passes over South America, because the Earth has rotated underneath it. Play around by tilting your left fist while making the angled "orbit" with your right index finger and you'll get the idea -- sometimes your finger crosses over your knuckles, sometimes over your palm, sometimes over the backs of your fingers, etc. The three curves show you the "offset" of the ISS' orbit with respect to the Earth's rotation.

Why they do this kind of orbit is so that the ISS will cover most of the globe at one time or another.

Answer 2

The ISS is going around the globe of the Earth, but not parallel to the equator. The orbit is inclined so on most flat map projections it looks like a wavy line. But the true path is not wavy at all. It would look much less confusing on a globe.

Answer 3

the map is only a representation of the earths surface, were you to look at it in three dimensions, the up/down would become a straight line representing the flight path of the iss as it passes over the ground below, the multiple lines mean that the iss is in steady speed asto movement, and the earth keeps moving away in one direction with every orbit. all of the orbiting sats display this characteristic and any of them could inter sect any other at any given time

Answer 4

I think they might be land elevation , if the lines are closer together there is a mountain formation.and the farther apart they are it is more of flat land.im not to sure ,some one here can probaly help you out better, just taking a wild guess.