Size distribution for unknown asteroids in Hubble asteroid hunter survey

This graph is based on Hubble Space Telescope archival data that were used to identify a largely unseen population of very small asteroids. The asteroids were not the intended targets, but instead photobombed background stars and galaxies in Hubble images. The comprehensive treasure hunt required perusing 37 000 Hubble images spanning 19 years. This was accomplished by using ‘citizen science’ volunteers and artificial intelligence algorithms. The payoff was finding 1701 trails of previously undetected asteroids.

[Image description: This graph plots the size of asteroids versus their abundance, based on a Hubble Space Telescope archival survey that found 1701 mostly previously undetected asteroids lying between the orbits of Mars and Jupiter. The vertical axis lists the number of objects from zero to 70. The horizontal axis lists size, from zero kilometres on the left, to 2 kilometres on the right. The graph slopes up such that the most abundant asteroids detected by Hubble in the survey are 0.5 kilometres across in size.]