Colonization of The Asteroids - Advantages

Advantages

• Low gravity greatly reduces the cost and risk of "landing" compared to the much deeper gravity wells of the Moon or Mars, and simplifies construction technologies (such as cranes) and reduces structural strength requirements
• Large number of possible sites, with over 300,000 asteroids identified to date
• Asteroids' chemical composition varies (see asteroid spectral types), providing a variety of materials usable in building and fueling spacecraft and space habitats.
• Some Earth-crossing asteroids require less energy (delta-v) to reach from Earth than the Moon.
• Material mined from asteroids could be a basis for a trade economy, and precious metals may even be returned to Earth or other colonized worlds from asteroid mines for economic gain.
• High surface-to-volume ratio enables effective exploration and exploitation of mineral resources and provides maximal portion of useful building ground on the surface and interior.
• High vacuum and low gravity would facilitate the evolution of some hi-tech industries such as material engineering and physical electronics (crystal growth, epitaxy).
• Many asteroids (especially the extinct comet cores) contain large amounts (more than 5% of total composition) of water and other volatiles, as well as carbon, which are all necessary for life support.
• Isaac Asimov pointed out the advantage of building cities inside hollowed out asteroids, since the volume of all the asteroids put together is a great deal more than that of a mile-high building covering the Earth would be, and thus could accommodate a large population.