NASA's Messenger Spacecraft Returns To Mercury

Oct 01, 2008
Messenger Spacecraft
This artist's impression shows NASA´s Mercury-bound MESSENGER from the sunshade side. The sunshade shields the spacecraft's instruments from heat and solar radiation. Image Credit: Johns Hopkins University Applied Physics Laboratory

(PhysOrg.com) -- A NASA spacecraft will conduct the second of three flybys of Mercury on Oct. 6 to photograph most of its remaining unseen surface and collect science data.

The MErcury Surface, Space ENvironment, GEochemistry, and Ranging, or MESSENGER, spacecraft will pass 125 miles above the planet's cratered surface, taking more than 1200 pictures. The flyby also will provide a critical gravity assist needed for the probe to become, in March 2011, the first spacecraft to orbit Mercury.

"The results from MESSENGER's first flyby of Mercury resolved debates that are more than 30 years old," said Sean C. Solomon, the mission's principal investigator from the Carnegie Institution of Washington. "This second encounter will uncover even more information about the planet."

During the spacecraft's first flyby on Jan. 14, its cameras returned images of approximately 20 percent of Mercury's surface never before seen by space probes. Images showed that volcanic eruptions produced many of Mercury's plains, its magnetic field appears to be actively generated in a molten iron core, and the planet has contracted more than previously thought.

"This second flyby will show us a completely new area of Mercury's surface, opposite from the side of the planet we saw during the first," said Louise M. Prockter, instrument scientist for the spacecraft's Mercury Dual Imaging System at the Johns Hopkins University Applied Physics Laboratory, or APL, in Laurel, Md.

The second flyby is expected to yield more surprises about the unique physical processes governing Mercury's atmosphere, as well as additional information about the charged particles located in and around Mercury's dynamic magnetic field. An altimeter on the spacecraft will measure the planet's topography, allowing scientists, for the first time, to correlate high-resolution topography measurements with high-resolution images.

A major goal of the orbital phase of the mission is to determine the composition of Mercury's surface. Instruments designed to make those measurements will get another peek at Mercury during this flyby.

"We will be able to do the first test of differences in the chemical compositions between the two hemispheres viewed in the two flybys," said Ralph McNutt, the mission's project scientist at APL. "Instruments also will provide information about portions of Mercury's surface in unprecedented detail."

The spacecraft is more than halfway through a 4.9-billion-mile journey to enter orbit around Mercury that includes more than 15 trips around the sun. In addition to flying by Mercury, the spacecraft flew past Earth in August 2005 and past Venus in October 2006 and June 2007.

Provided by NASA

Explore further: Heavy metal frost? A new look at a Venusian mystery

add to favorites email to friend print save as pdf

Related Stories

Watch the "blood moon" eclipse from Mercury (w/ Video)

Oct 13, 2014

Yes, it's another time-lapse of the October 8 lunar eclipse that was observed by skywatchers across half the Earth… except that these images weren't captured from Earth at all; this was the view from Mercury!

NASA image: Flying through an aurora

Sep 10, 2014

European Space Agency astronaut Alexander Gerst posted this photograph taken from the International Space Station to social media on Aug. 29, 2014, writing, "words can't describe how it feels flying through ...

NASA's MESSENGER spacecraft's 10 years in space

Aug 05, 2014

Ten years ago, on August 3, 2004, NASA's MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging) spacecraft blasted off from Cape Canaveral, Florida, for a risky mission that would take ...

The most precise measurement of an alien world's size

Jul 24, 2014

Thanks to NASA's Kepler and Spitzer Space Telescopes, scientists have made the most precise measurement ever of the radius of a planet outside our solar system. The size of the exoplanet, dubbed Kepler-93b, ...

Recommended for you

Heavy metal frost? A new look at a Venusian mystery

6 hours ago

Venus is hiding something beneath its brilliant shroud of clouds: a first order mystery about the planet that researchers may be a little closer to solving because of a new re-analysis of twenty-year-old ...

Hot explosions on the cool sun

12 hours ago

(Phys.org) —The Sun is more spirited than previously thought. Apart from the solar eruptions, huge bursts of particles and radiation from the outer atmosphere of our star, also the cooler layer right below ...

Europe secures new generation of weather satellites

13 hours ago

Contracts were signed today to build three pairs of MetOp Second Generation satellites, ensuring the continuity of essential information for global weather forecasting and climate monitoring for decades to ...

User comments : 0