October 29, 2021
Today in 1991, the space probe Galileo became the first human object to fly past an asteroid. The encounter provided data and over 150 images of the asteroid Gaspra in the main asteroid belt. Gaspra is approximately 20 kilometers wide.
This picture of asteroid 951 Gaspra is a mosaic of two images taken by the Galileo spacecraft from a range of 5,300 kilometers (3,300 miles), some 10 minutes before closest approach on October 29, 1991. Credit: NASA/JPL/USGS