On this day in space! Aug. 3, 2004: MESSENGER spacecraft launches to Mercury (Image Credit: Space.com)
On Aug. 3, 2004, NASA launched the MESSENGER spacecraft on a historic first mission to orbit the planet Mercury.
The spacecraft’s name stands for the MErcury Surface, Space ENvironment, GEochemistry and Ranging mission. It blasted off from Cape Canaveral Air Force Station in Florida at 6:15 a.m. Eastern Time and spent the next six and a half years making its way to Mercury’s orbit.
Because Mercury is so close to the Sun, a spacecraft traveling toward the planet speeds up as the sun’s gravity pulls it in.
In order to slow down enough to avoid falling into the sun, MESSENGER utilized the gravitational pull of Venus and Mercury with multiple flybys along the way. It made 15 trips around the sun before it finally arrived in Mercury’s orbit in 2011.