MESSENGER team celebrates orbital anniversary, reports on new findings

March 17, 2014
MESSENGER at Mercury
Artist's concept of the NASA's MESSENGER spaceraft at Mercury. Credit: NASA

Today, the MESSENGER team celebrates the third anniversary of the probe's Mercury orbit insertion. On March 17, 2011 (Eastern Daylight Time), the spacecraft made history when it became the first probe to orbit the innermost planet. Over the last three years, MESSENGER instruments have fully mapped Mercury's surface and yielded discoveries that have changed views on how the inner planets formed and evolved.

The latest findings will be described in 25 papers presented this week at the 45th Lunar and Planetary Science Conference in The Woodlands, Texas. Now—as a key part of MESSENGER's second extended mission—the team is preparing to embark on a low-altitude imaging campaign that promises to reveal even more information about Mercury.

The altitude of the at closest approach has been slowly decreasing as the Sun's gravity perturbs its around Mercury, and the progressively closer approaches will provide MESSENGER's instruments with an unprecedented opportunity to make high-resolution observations of the planet. For example, the hollows first revealed by the probe's instruments in 2011 are suspected to have formed because volatile elements sublime off the surface, but observations to date could not confirm this hypothesis.

At spacecraft altitudes below 350 kilometers, the Mercury Dual Imaging Instrument's Narrow Angle Camera will acquire images with pixel scales ranging from 20 meters to as little as 2 meters. Such high-resolution images will reveal small features of the enigmatic hollows for the first time. "We will be seeing features at up to 10 times the resolution of the images acquired so far," noted MESSENGER Co-Investigator Scott Murchie of the Johns Hopkins University Applied Physics Laboratory (APL).

"Our spacecraft team is delighted to celebrate the third anniversary of MESSENGER's at Mercury," adds MESSENGER Principal Investigator Sean Solomon, of Columbia University's Lamont-Doherty Earth Observatory. "However, some of the most exciting observations from the mission are still to come. We can expect new surprises as we view the innermost planet from closer range than ever before achieved by spacecraft."

The lowest point of MESSENGER's orbit is now 226 kilometers (140.4 miles) above Mercury's surface. This minimum altitude will continue to decrease until the first maneuver of the mission's low-altitude campaign in mid-June 2014. Following the maneuver, the spacecraft's altitude at will continue to decrease until raised by additional maneuvers in September 2014, October 2014, and January 2015. At that point, MESSENGER will have spent its onboard fuel, and additional maneuvers to raise the minimum altitude will not be possible. In March 2015, the spacecraft will impact the surface of Mercury, having successfully completed four years in orbit about Mercury.

Explore further: MESSENGER Surpasses 200,000 Orbital Images of Mercury

Related Stories

MESSENGER Surpasses 200,000 Orbital Images of Mercury

February 6, 2014

MESSENGER has now returned more than 200,000 images acquired from orbit about Mercury. The 1996 proposal for the mission promised a return of at least 1,000 images says Robert Gold, MESSENGER's Science Payload Manager. "We ...

Image: Sunlit side of the planet Mercury

October 29, 2013

Another day, another beautiful view of Mercury's horizon. In this scene, which was acquired looking from the shadows toward the sunlit side of the planet, a 120-km (75 mi.) impact crater stands out near the center. Emanating ...

MESSENGER Returns Images from Oct. 6 Mercury Fly-By

October 7, 2008

MESSENGER is the first mission sent to orbit the planet closest to the sun. On Oct. 6, 2008, at roughly 4:40 a.m. ET, MESSENGER flew by Mercury for the second time this year. During the encounter, the probe swung just 125 ...

Recommended for you

Dwarf galaxies shed light on dark matter

January 23, 2017

The first sighting of clustered dwarf galaxies bolsters a leading theory about how big galaxies such as our Milky Way are formed, and how dark matter binds them, researchers said Monday.

One of the brightest distant galaxies known discovered

January 23, 2017

An international team led by researchers from the Instituto de Astrofísica de Canarias (IAC) and the University of La Laguna (ULL) has discovered one of the brightest "non-active" galaxies in the early universe. Finding ...

Freeze-dried food and 1 bathroom: 6 simulate Mars in dome

January 20, 2017

Crammed into a dome with one bathroom, six scientists will spend eight months munching on mostly freeze-dried foods—with a rare treat of Spam—and have only their small sleeping quarters to retreat to for solace.

Image: Wavemaker moon Daphnis

January 20, 2017

The wavemaker moon, Daphnis, is featured in this view, taken as NASA's Cassini spacecraft made one of its ring-grazing passes over the outer edges of Saturn's rings on Jan. 16, 2017. This is the closest view of the small ...

Video: A colorful 'landing' on Pluto

January 20, 2017

What would it be like to actually land on Pluto? This movie was made from more than 100 images taken by NASA's New Horizons spacecraft over six weeks of approach and close flyby in the summer of 2015. The video offers a trip ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.