
Each ISS solar array wing (often abbreviated "SAW") consists of two retractable "blankets" of solar cells with a mast between them. Each wing is the largest ever deployed in space, weighing over 2,400 pounds and using nearly 33,000 solar arrays, each measuring 8-cm square with 4,100 diodes. When fully extended, each is 35 metres (115 ft) in length and 12 metres (39 ft) wide. Each SAW is c.

In many prehistoric and ancient cultures, the Sun was thought to be a solar deity or other entity. In the early first millennium BC, observed that the Sun's motion along the is not uniform, though they did not know why; it is today known that this is due to the movement of Earth in an , moving faster when it is nearer to the Su.

Space-based solar power (SBSP or SSP) is the concept of collecting in with solar power satellites (SPS) and distributing it to . Its advantages include a higher collection of energy due to the lack of and absorption by the , the possibility of very little night, and a better ability to orient to face the Sun. Space-based solar power systems convert

The Solar System formed at least 4.568 billion years ago from the gravitational collapse of a region within a large . This initial cloud was likely several light-years across and probably birthed several stars. As is typical of molecular clouds, this one consisted mostly of hydrogen, with some helium, and small amounts of heavier elements by previous generations of stars.

The Kuiper belt is a in the outer , extending from the of at 30 (AU) to approximately 50 AU from the . It is similar to the , but is far larger—20 times as wide and 20–200 times as . Like the asteroid belt, it consists mainly of or remnants from when the . While many are.