January 25th in Astronomy and Space Science
![]() | 1736 | French-Italian astronomer and mathematician Joseph-Louis Lagrange born. He made important contributions to the fields of differential equations, linear algebra, and number theory. His work in astronomy included an understanding of lunar motion, the effects of planets on cometary orbits, and a solution to the three body problem. The latter work showed that there are stable points near the orbit of any body where smaller bodies can remain almost indefinitely. Today these are called Lagrange Points. |
![]() | 1870 | British astronomer and optician William Buffham becomes the first to observe and record markings on Uranus. |
![]() | 1964 | US launches the Echo 2 passive communications satellite - essentially a large metalized balloon which reflects radio signals. This mission marks the first cooperation in space between the US and USSR. The Soviets agreed to track Echo 2 when over their territory and also provided photographic records of it's inflation stage. However, the US military also used Echo 2 as an astronomical reference point to refine the location of Moscow for missile targeting. |
![]() | 1994 | The US Clementine spacecraft launched. It spends 90 days in lunar orbit, mapping the surface with a resolution of 125-250 m (410-820 feet) and obtaining altimeter data that enabled the first detailed topographic map of the Moon. |
![]() | 2004 | The Mars Exploration Rover Opportunity lands on Mars, in the region of Terra Meridiani. |