NASA's Shuttle Discovery launching from Pad 39A on STS-60, February 3, 1994
All rockets are assembled and launched from a spaceport. Here, the payload is placed into the rocket, the vehicle’s hardware and software are tested and the propellant is fed to the engines, amongst many other tasks to prepare the vehicle for launch. Once this is done, the vehicle must be ready for a specific launch window. This is the period of time during which a spacecraft can be launched into its particular orbit from its launch site. Depending on what it is used for, the spacecraft will be bringing to space different payloads that will be used at certain altitudes, or orbits. The rocket must be launched at the right time and in the right direction because this window of time is when the orbit and launch site cross paths. Other restrictions also exist that may prevent a rocket from launching, which primarily includes weather, as well as political considerations.
Common and well-known launch sites include Florida’s Cape Canaveral Air Force Station near the NASA Kennedy Space Center, the European spaceport located to the northwest of Kourou in French Guiana, and the oldest launch site, Kazakhstan’s Baikonur Cosmodrome, which is on lease to Russia and has supported more than 1,000 launches to space.
A Soyuz rocket is placed into position at the Baikonur Cosmodrome's Pad 1/5 in March 2009.
Most of the world’s launch sites are located near the equator. This is because while the Earth rotates on its axis, it is spinning at a greater speed at the equator is than at the poles of the planet. Rockets launched here can therefore benefit from the rotation of the Earth, which acts as a natural boost that can help cut costs of fuel. In fact, at the equator, the planet's speed of rotation is over 460 meters per second.
Launches also often take place near the ocean to lower the risk of damage from a possible failure or explosion that could take place shortly after launch. These launch sites near the ocean are usually on the east coast because the Earth rotates from west to east. This means that when a rocket launches, it flies over the ocean as the planet rotates below to further lower the likelihood of damage if an accident happens. For example, if an explosion were to occur shortly after launch, the majority of debris would fall to the ocean instead of on land (where it could pose a danger to underlying cities). These sites are also large enough and sufficiently removed from nearby urban or populated centers to minimize any risk of damage, should any emergency occur.
Recently, the word "spaceport" has also been used to describe launch sites that are located in space. For example, space stations and proposed bases on the moon and Mars have been called spaceports. This is because these locations could be used as a launch location or base for for future space missions. Furthermore, Earth's spaceports are now being challenges with logistical and legal matters in order to accommodate for the growing interest in space tourism, which is expected to be operational within the coming years.