Template:Are You Sure/October 5

Viking 2 Orbiter image of the Martian satellite Deimos taken from 1400 km. Deimos appears smooth, but higher resolution images taken during closer approaches show the surface is covered with craters, but many of these have been partially buried or subdued by regolith. Deimos is about 14 km from top to bottom in this image. Date: 5 October 1977.

• ... that mathematician Benjamin Peirce (4 April 1809 – 6 October 1880) made contributions to celestial mechanics, statistics, number theory, algebra, and the philosophy of mathematics; and that Peirce famously stated: "Mathematics is the science that draws necessary conclusions"?