Finding Asteroids

Scientists estimate there are 20,000 asteroids in the Solar System 100 meters across or larger.  So far, we've discovered about 8,000.  Further, at the historical rate of discovery, a new study says finding and characterizing the material makeup of the rest will take about two more centuries.  Given the damage an asteroid strike could do to Earth, that length of time is worrisome.

Of course, with the increased use of constantly improving technology and techniques, that historical rate will be bettered.  Still, the study calls for an increased emphasis on finding them, including deployment of a space-based telescope dedicated to the purpose.

Asteroids are not simply dangerous, however-- nor simply scientifically interesting.  They also contain vast quantities of precious matals, water ice, and other valuable materials that could support human expansion beyond Earth, and even economic development on Earth.  Two private companies, Planetary Resources and Deep Space Industries, are planning to go asteroid hunting for profit.  That would also increase the discovery rate.