The greatest bonus is at the equator since that is the farthest from the axis of rotation. If you consider this speed boost, then what is the energy to get into orbit per kg as a function of latitude? Here you go.
Launching from Cape Canaveral Maybe that doesn't seem like a big deal, but every bit helps. Moving towards the equator gives you a little speed boost. Moving to a mountain would make the change in gravitational potential energy to get to orbit a bit smaller. Suppose the mountain has a height of s I already used h for the orbit height.
This would change my change in energy equation to:. This assumes starting the mass at rest so no speed boost. Mount Everest is 8, meters above sea level. So, here is a plot of the energy needed to get 1 kg into low Earth orbit for heights starting from sea level to the top of Everest. Launching from the top of Mount Everest would give you a 0. This would be the best case scenario, wouldn't it?
If there was an 8,meter high mountain at sea level, it would do two things. First it would start the rocket off at a higher point. Second it would give it even more of a starting speed than at the equator. Because it isn't on the equator. It is 8, meters above the equator.
But is that a big difference? The speed at sea level on the equator is using a rotation period of 23 hours and 56 min :. There's an alternate way to apply benefits: keeping the payload mass constant, but sending it to a higher orbit. If you're launching into a retrograde orbit opposite of the way the Earth turns , then being closer to the equator is a disadvantage.
Israel faces this problem as the only safe direction to launch their orbital rockets is to the west. I believe they orbit things in an approximately degree inclination. Latitude is not the only factor in choosing sites. Other factors include weather, security USSR chose a central inland area for this , and transportability Cape Canaveral is transportable by sea barge, so they can ship huge rockets without a problem.
Don't assume that the ratio of masses for any two examples in the chart will be the same ratio for the same latitudes of a different rocket. You really need to look at the rocket's final stage, see what it's Ve is and other parameters. Then use those numbers in the equations and make your own chart.
Earth isn't a perfect sphere. Equatorial radius is actually a bit more than km. There may also be a mountain or plateau somewhere that would give a decent boost by extra radius which yields extra ground speed and extra height above mean sea level which yields less vertical acceleration needed. Of course, remote and inhospitable areas incur their own expenses if you're really thinking about building there, but these sort of boosts once spawned the concept of balloon-launched rockets, and still today there is talk of rockets launched from airplanes as well as those exotic launch systems like the Launch Loop which can run up a mountainside for the same "Newton's Cannonball" physical boost.
There's my answer based purely on math. If you dare, you can plug in your own example and figure out the exact benefits for your specific case. So, from NASA's point of view, they might be able to add several million dollars of payload value to a launch if they launched from, for example, the Marshall islands only a few degrees off the equator, where some American rockets have been launched or Puerto Rico 18 degrees North But this cost advantage is negated by the cost of logistics and communications with a remote launch site.
The bigger issue is that the Mediterranean region is both a busy shipping lane and a region containing many different and often densely populated countries, which would make approval extremely difficult. It has open ocean to the East so is ideally sited from the point of view of range safety which was a huge issue in times when countries were much less trusting of one another.
France offered the site for use by the ESA. It ought to have been a no-brainer to select Kourou as the ESA's site, as it would avoid all the regulatory and national security issues as well as any national pride arguments as to which country the launch site should be in which given the slowness of European multigovernmental collaborations could have paralysed the programme for decades.
It should also be noted that in the Iron Curtain was not far from the Italian Border, and Spain was transitioning from dictatorship to democracy, so neither of these countries was really a viable option at that time.
Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. How much of an advantage do equator-proximal launch sites provide? Ask Question. Asked 8 years, 3 months ago. Active 3 years, 9 months ago. Viewed 19k times. Improve this question. Add a comment. Active Oldest Votes. Why was Cape Canaveral chosen? Why does NASA not relocate somewhere else?
What is the gain in terms of payload mass when launching from Kourou? From Moonport : Cape Canaveral, better known as "the Cape," had been earmarked as a missile testing range in The likely list of inclinations to launch into. Moonport: A Saturn Launch Site With better than 20 years' experience, the von Braun team preached and practiced that rocket and launch pad must be mated on the drawing board, if they were to be compatible at the launching. By Charles D.
Benson and William Barnaby Faherty. Improve this answer. Community Bot 1. Deer Hunter Deer Hunter But guess what. It's not over: This only holds for launches due east. Why the equator? Believe it or not, the surface of the Earth is traveling faster there.
If you look at two spots on one line from pole to pole, one spot on the equator and the other halfway to the pole, each will make a complete revolution in 24 hours and return to where it was. But since the Earth's shape is round, and the widest point is at the equator the spot on the equator would have to go more miles in that twenty four hours. That means that the land is moving faster at the equator than any other place on the surface of the Earth.
How do we put a spacecraft into orbit? How can a spaceship leave orbit?
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