(MEDIA GENERAL) – Eleven years after its launch, NASA announced the MESSENGER mission is expected to conclude April 30 when the spacecraft will run out of propellant and crash to the planet’s surface.
The MESSENGER spacecraft (MErcury Surface, Space ENvironment GEochemistry and Ranging) is expected to impact the planet at more than 8,750 miles per hour (3.91 kilometers per second).
The mission, controlled at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland, has completed a series of maneuvers to keep the spacecraft in orbit. The final maneuver is scheduled for April 24.
“Following this last maneuver, we will finally declare the spacecraft out of propellant, as this maneuver will deplete nearly all of our remaining helium gas,” said Daniel O’Shaughnessy, mission systems engineer at APL. “At that point, the spacecraft will no longer be capable of fighting the downward push of the sun’s gravity.”
MESSENGER traveled for more than six and a half years before entering Mercury’s orbit. The mission was to orbit the planet and collect data for one Earth year. According to a NASA press release, “The spacecraft’s healthy instruments, remaining fuel and new questions raised by early findings resulted in two approved operations extensions, allowing the mission to continue for almost four years and resulting in more scientific firsts.”
Two of MESSENGER’s important findings focus on the planet’s polar regions. A key finding in 2012 provided “compelling support” for the hypothesis that Mercury has “an abundance of frozen water and other volatile materials” within its polar craters. Through this data, some researchers argue the presence of organic compounds within Mercury’s ice gives credence to the hypothesis that organic compounds “were delivered from the outer solar system to the inner planets and may have led to the prebiotic chemical synthesis and, thusly, life on Earth.”
Aside from its findings, MESSENGER led to confirmation of new technologies, notably the sunshade used to protect the spacecraft’s instruments from direct solar radiation.
“The front side of the sunshade routinely experienced temperatures in excess of (570 degrees Fahrenheit), whereas the majority of components in its shadow routinely operated near room temperature (68 degrees Fahrenheit),” said Helene Winters, mission project manager at APL.
“For the first time in history we now have a real knowledge about the planet Mercury that shows it to be a fascinating world as part of our diverse solar system,” said John Grunsfeld, associate administrator for the Science Mission Directorate at NASA headquarters in Washington D.C. “While spacecraft operations will end, we are celebrating MESSENGER as more than a successful mission. It’s the beginning of a longer journey to analyze the data that reveals all the scientific mysteries of Mercury.”