December 7, 2009, marks the eighth anniversary of the Jason-1 launch. The spacecraft has now completed more than 37,592 orbits, accurately measuring the surface topography of 95 percent of the world's ice-free ocean every 10 days for the past eight years. As it moves into its ninth year of operation, Jason-1 has delivered more than 99 percent of available mission data to the 400 members of the international science team.
With the launch of OSTM/Jason-2 in June 2008, Jason-1 became NASA's senior ocean altimetry satellite. It took over the title from its predecessor TOPEX/Poseidon, which ended after more than 13 years of operations in December of 2005. In January 2009, Jason-1 was maneuvered into a parallel orbit to Jason-2. The two spacecraft now fly in a tandem configuration. In this tandem mode, they obtain global ocean coverage every 4.5 days, resulting in twice the amount of data provided to scientists and marine operators. Jason-1 and TOPEX/Poseidon operated in a similar configuration for more than three years, proving the double-teaming power of the tandem mission.
Monitoring the ocean by measuring global ocean surface topography has proven to be critical in understanding the ocean's role in climate. Congratulations to the entire Jason-1 team on reaching this important milestone We all hope for more years of smooth sailing... above the ocean.