Basalt is an extrusive igneous rock formed by the rapid cooling of lava. This Earth rock has been included because it is an analogue (meaning it can be considered a “stand in” or a very similar type of rock) for the basalt that has been discovered on the Moon. That the Moon is mainly made of anorthosite and basalt suggests that not only was it once volcanic (the Moon’s Mares, or ‘seas’ contain fewer craters since they were filled with volcanic lava), but also that the Moon was originally part of our planet.
All images on this page are credit to National Space Centre unless otherwise stated.
Click the animated image to open the Basalt 3D viewer. This allows you to rotate the Basalt rock, move it around, zoom in and out, measure the size and more.
Last updated: 01 November 2018