Asteroids are the best real estate in the Solar System.
Despite their celestial age, our understanding of asteroids is still in its infancy. However, the more we learn about them, the more enticing destinations they become.
Asteroids are primordial material left over from the formation of the Solar System. They are scattered throughout it: some pass close to the Sun, and others are found out beyond the orbit of Neptune. A vast majority have been collected by Jupiter’s gravity into a belt between it and Mars – an area known as the Main Belt. As it turns out, we have been discovering thousands of asteroids that do not belong to the Main Belt, but instead pass near Earth’s orbit – nearly 9,000 to date, with almost a thousand more discovered every year.
Many of these near-Earth asteroids are easily accessible from Earth. And many contain enormous quantities of accessible resources.
An Incredible Resource
There are over 1,500 asteroids that are as easy to get to as the surface of the Moon. They are also in Earth-like orbits with small gravity fields, making them easier to approach and depart.
Asteroid resources have some unique characteristics that make them especially attractive. Unlike Earth, where heavier metals are close to the core, metals in asteroids are distributed throughout their body, making them easier to extract.
Asteroids contain valuable and useful materials like iron, nickel, water, and rare platinum group metals, often in significantly higher concentration than found in mines on Earth.
We are only just beginning to realize the incredible potential of asteroids. The first encounter of a spacecraft with an asteroid was in 1991, as the Galileo spacecraft flew by the 951 Gaspra asteroid on its way to Jupiter. Our knowledge of these celestial neighbors has been revolutionized by a small set of US and international missions carried out since that time. With each visit or fly-by, the science on asteroids has been rewritten.