MErcury Surface, Space ENvironment, GEochemistry and Ranging (MESSENGER) spacecraft

MErcury Surface, Space ENvironment, GEochemistry and Ranging (MESSENGER) spacecraft

NASA/Goddard Space Flight Center/Arizona State University

The first spacecraft to visit Mercury was Mariner 10 (1975). Nearly 40 years later, MESSENGER is the second spacecraft to visit Mercury. MESSENGER spent 4 years getting to Mercury, performed several flyby missions where it mapped the planet and gathered data, and finally entered into orbit in 2011. MESSENGER will spend at least 1 year gathering data while it orbits.

August 3, 2004

March 18, 2011

End of Mission
Still operating as of 2012

Understand the history, origin, and evolution of Mercury and the other terrestrial planets. Map the planet in color, image the surface in high resolution. Measure the composition of the surface, atmosphere, and magnetic field.

MESSENGER seeks answers to these questions:

  1. Why is Mercury so dense?
  2. What is the geologic history of Mercury?
  3. What is the structure of Mercury’s core?
  4. What is the nature of Mercury’s magnetic field?
  5. What are the unusual materials at Mercury’s poles?
  6. What volatiles (gases involved in volcanic eruptions) are important at Mercury?

New data from the 2008 flyby shows that unlike the moon, Mercury has huge cliffs with structures snaking hundreds of miles across the planet’s surface. These cliffs preserve a record of fault activity from early in the planet’s history. Images revealed impact craters that appear very different from lunar craters. A unique feature was discovered, the Spider. The Spider consists of more than a hundred narrow, flat-floored troughs radiating from a central region. Similar to Earth, Mercury has magnetic fields caused by a liquid metallic outer core deep in the planet’s center.