NASA’s Messenger (MErcury Surface, Space ENvironment, GEochemistry and Ranging) spacecraft was the first to ever orbit Mercury. The mission was intended to orbit Mercury for one Earth year, but it stayed for more than four years, making new scientific discoveries about the planet closest to the Sun.
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
In February 2004, Messenger exited a thermal vacuum chamber at NASA’s Goddard Space Flight Center after testing showed it could withstand the steep temperature variations it would face on the mission to Mercury.
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
After a 6.5-year journey around Earth and Venus, Messenger arrived at its destination, Mercury, and sent back the first of many images and data from its orbit around the innermost planet of the Solar System.
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
In 2013, Messenger captured a shot of a crater that NASA says is “relatively young,” as in less than 1 billion years old. The signs of its youth include the rays, defined peak and small number of overlying craters.
Credit: NASA/Johns Hopkins University Applied Physics
A side view of Mercury shows its many craters, including the bright rays of the Han Kan crater.
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
Messenger’s Wide Angle Camera instrument captures the Hovnatanian crater, named for the Armenian painter Hakop Hovnatanian. The rays’ brightness indicates the features have not been on on Mercury's surface for very long, and the crater’s butterfly pattern likely was caused by an oblique impact.
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
Not only did Messenger provide a close-up look at the Solar System’s innermost planet, the spacecraft also got close enough to the Sun, 28 million mi., to detect neutrons created in solar flares.
Credit: NASA/Solar Terrestrial Relations Observatory/Helioviewer
The Shakespeare basin, the Messenger spacecraft’s crash site, is shown here on the bottom left corner. The basin appears smooth, likely because of past lava flooding at the location.
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
On April 30, 2015, Messenger sent home its final image of Mercury’s surface before crashing into the planet north of Shakespeare basin. The final image shows the floor of a crater called Jokai.
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington