21 September

2003: On 21 September 2003, the NASA Galileo spacecraft ended its eight-year mission to Jupiter. The Jet Propulsion Laboratory in Pasadena, California, directed the craft into Jupiter's atmosphere to burn up. This prevented the possibility of any later uncontrolled fall onto a moon causing contamination with bacterial life from Earth, perhaps carried on the probe since launch.

Galileo was a mission to study Jupiter and its moons Ganymede, Callisto, Io and Europa.

Around 21 September every year is the Autumn Equinox in the northern hemisphere and the Spring Equinox in the southern hemisphere. The Sun is at its highest path in the sky at the Summer Solstice. After that day the Sun follows a lower and lower path through the sky each day until it is in the sky for exactly 12 hours everywhere on Earth – it is following a track over Earth's equator. After the Autumn Equinox, the Sun continues to follow a lower and lower path through the sky, with the days growing shorter and shorter and longer until it reaches it lowest point in the sky at the Winter Solstice.