1995: On 2 December 1995, the ESA/NASA Solar and Heliospheric Observatory (SOHO) was launched.
SOHO flies in a halo orbit around the Lagrangian point, L1 - about 1.5 million kilometres from Earth towards the Sun.
Data from SOHO helps us understand the Sun. It is the only star we can observe in such detail and the star on which we all depend. Its science ranges from the Sun's hot interior, through its visible surface and stormy atmosphere, to distant regions where the wind from the Sun meets atoms coming from other stars.
1993: On 2 December 1993, Space Shuttle Endeavour was launched and performed the first Hubble Space Telescope Servicing Mission (codenamed STS-61).
It was a ten-day mission with five space walks. This mission repaired faulty optics on the NASA/ESA Hubble Space Telescope allowing astronomers a new, clear view of space.