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As per our current scientific knowledge the earth rotates on its axis and it rotates at a speed of 1670 kilometers/hour. This decreases by the cosine of your latitude so that at a latitude of 45 degrees, cos(45) = .707 and the speed is .707 x 1670 = 1180 kilometers/hr

Earth atmosphere has 5 distinct layers :

  1. First there is the troposphere, which contains more than half of the overall atmosphere. Near the poles, it starts at the Earth’s surface and stretches more than 30,000 ft (9 km), and about 56,000 ft (17 km) at the Equator

  2. The Second layer is the stratosphere ,it begins where the troposphere ends, extending above 31 miles (50 km) above that. This is where many airplanes fly, due to the stability of this layer.

  3. Going onward up, there is the mesosphere — the area in which meteors generally burn up
  4. Just above the mesosphere is the thermosphere
  5. Exosphere is the area where earth atmosphere ultimately merges with space. Space starts at 188 KM above the earth surface.

Keeping all the above in perspective, Let’s say that a space craft reaches an altitude of 800 KM above the earth surface and is well outside the earth’s atmosphere. Now since the earth below is rotating, would the space craft be able to land in different places by just hovering above and making a straight vertical descent. This would eliminate all horizontal travel distance as done by the airplanes when traveling from one point to another. Once we are at 800 km above the earth surface, all that is needed is to wait for the appropriate time when as a result of rotation of the earth, your destination point passes right under you and you descent your space craft to your destination. Do you think that this could revolutionize travelling? Less fuel and less time by just taking advantage of the rotation of the earth?

I am also attaching a diagram to clarify my question. The Diagram shows the various layers of earth’ atmosphere. The Orange tube just shows the vertical descent I am talking about from Point A in outer space (say at 800 km above the surface of earth). The Yellow line is the Imaginary karman line at distance of 110 km which serves the boundary between the earth’s atmosphere and the region where the space begings.

Please comment if the idea is feasible and the areas where you see flaws in this theory. One possible argument that people can give in the opposition of the idea is :

“Motion is relative and that the earth’s atmosphere rotates with the same velocity as the earth itself and therefore our spacecraft in question would also be in same motion as the atmosphere” - Relative Motion Concept Please note that the relative motion concept would not apply in the case presented above because my assumption is that the space craft is no longer in earth’s atmosphere and is way beyond the karman line and cannot be considered as inside the earth’s atmosphere. The Space craft is 800 KM above the surface of the earth. Do you think that this idea of vertical travelling taking advantage of earth’s rotation is possible? Please comment. Your feedback would be greatly appreciated.

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Qmechanic
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Ahmad Siasi
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    You realize that 800 km is in the low-earth orbit (LEO)? And that to get to LEO, we need rockets, not airplanes, right? – Kyle Kanos Sep 20 '14 at 01:38
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    To add to what Kyle wrote, an object at an altitude of 800 km is in orbit, moving at about 7.5 kilometers per second. You can't "just hover". – David Hammen Sep 20 '14 at 01:50
  • just two cents: you do need to be "in orbit", but if you want to stay at a given altitude you will need to keep you rocket on, otherwise you will fall back to earth. I have no idea if that woul de more efficient than an airplane but my guess is a "no". –  Sep 20 '14 at 02:02
  • Yes I know that we would need rockets not airplanes but at 800 km we will certainly be outside of the earth's atmosphere . Now the question is would the space at 800 km also be rotating at the same speed as earth? It is assumed that when the earth rotates the surrounding gases in the five layers of atmosphere rotate with it but I am talking well beyond the 5 layers that's why I mentioned 800 km ! – Ahmad Siasi Sep 20 '14 at 02:05
  • @david sorry for the using the word hovering here. What I meant here was being above the earth ....being able to see it rotation while in the LEO and make the downward descent when the destination passes under you as a result of earth's natural rotation. – Ahmad Siasi Sep 20 '14 at 02:16
  • the space does not rotate but Earth's gravity will pull you down unless you have at least that tangential speed (well, it will still pull you "down" but your trajectory will be circular) –  Sep 20 '14 at 02:31
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    possible duplicate of Why does the atmosphere rotate along with the earth? – Brandon Enright Sep 20 '14 at 05:09
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    Why does this have three close votes for not mainstream physics? This is a simply question about dynamics so how can it possibly be not mainstream physics? – John Rennie Sep 20 '14 at 05:16
  • Rockets are taking advantage of Earth's rotation. We are mostly launching in direction of the rotation, not against it, which reduces the delta v required to reach orbit by a couple hundred meter per second (that's quite a lot in terms of fuel/gain in payload). LEO starts at approx. 160km altitude, but hovering, at any altitude is basically impossible to do with current technology. – CuriousOne Sep 20 '14 at 06:09
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    Duplication Issue : I guess there are million of online users and some might have the same sort of basic questions. My question was my personal one and has not been fully addressed in the post which has been given as reference. Hope that sorts the duplication thing. This is not a thesis but a question. Question can be on the same lines or have some overlap of answers etc. – Ahmad Siasi Sep 20 '14 at 12:16
  • I agree that this basic question is asked repeatedly, and I came up with a somewhat general answer here: http://physics.stackexchange.com/questions/227391 –  Jan 04 '16 at 16:00

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