- 5 February 1974 – Mariner 10 becomes the first spacecraft to use a gravity assist when it flies by Venus in order to reach Mercury
- 5 February 2002 – HESSI (High Energy Solar Spectroscopic Imager) solar flare observatory is launched on a mission to explore the physics of particle acceleration and energy release in solar flares
- 10 February 2002 – Solar Orbiter is launched to perform detailed measurements of the inner heliosphere and nascent solar wind, and perform close observations of the polar regions of the Sun
- 15 February 1845 – The Leviathan of Parsonstown, the world's largest telescope from 1845 to 1917, sees first light
- 18 February 1930 – 23-year-old astronomer Clyde Tombaugh discovers Pluto by using a blink comparator on photographs he took in the previous month at Lowell Observatory
- 25 February 2002 – Mariner 6 is launched to study the surface and atmosphere of Mars during close flybys