Space Stations have to have power to run everything it has aboard. Space stations in the past to the present have used solar power to get their power. Space stations use solar rays given off by the sun, which is then turned into electricity to run the module. Eight solar arrays that cover approximately an acre each receive the sun light from the sun. To keep the arrays facing the sun the mast that holds the arrays turns on a gimbal (Work 11). On the arrays are tiny cells called photovoltaic cells that catch light and convert it to energy. Light is caught in the form of photons by solar cells. When the cells catch photons, one electron is then set free causing a hole to be formed where that electron was. The electric field will send the electron to the negative side and the hole will be sent to the positive side. This causes disruption because the free electron will want to unite with the hole again. The electron will then want flow back over to the positive side and it will cause current. The whole process done by the cell's electric field causes a voltage. When current and power are put together, power is produced (Cells 3). The arrays produce about 160 volts of DC electricity. The space station's equipment is ran by a 124-volt DC current transformer. Some of the equipment onboard runs on AC current so there is power converters to fix that problem. Excess power from the arrays is used to charge the batteries for when the ISS passes through the Earth's shadow (Work 11).
Moving around in space is essential to the ISS in space. Drag is created when the ISS is moving around. This slows down the module down very much. To maintain altitude or to orbit around the Earth, the ISS has to have to rocket engines. Rocket engines burn a high-pressure gas to be able to produce thrust. The way a rocket engine works is that it throws a mass of gas one way to produce a reaction the other way. The mass that is burned is the gas or fuel that is n