[meteorite-list] MESSENGER: A Closer Look at the Previously Unseen Side of Mercury

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Mon, 28 Jan 2008 17:23:00 -0800 (PST)
Message-ID: <200801290123.RAA02630_at_zagami.jpl.nasa.gov>

http://messenger.jhuapl.edu/news_room/status_report_01_28_08.html

MESSENGER Mission News
January 28, 2008

A Closer Look at the Previously Unseen Side of Mercury

Two weeks ago, on January 14, 2008, MESSENGER became the first
spacecraft to see the side of Mercury shown in this image. The first
image transmitted back to Earth following the flyby of Mercury
<http://messenger.jhuapl.edu/gallery/sciencePhotos/image.php?page=3&gallery_id=2&image_id=129>,
and then released to the web within hours, shows the historic first look
at the previously unseen side. This image
<http://messenger.jhuapl.edu/gallery/sciencePhotos/image.php?gallery_id=2&image_id=141&preview=Y>,
taken by the Wide Angle Camera (WAC) of the Mercury Dual Imaging System
(MDIS), shows a closer view of much of that territory.

Just above and to the left of center of this image is a small crater
with a pronounced set of bright rays extending across Mercury's surface
away from the crater. Bright rays are commonly made in a crater-forming
explosion when an asteroid strikes the surface of an airless body like
the Moon or Mercury. But rays fade with time as tiny meteoroids and
particles from the solar wind strike the surface and darken the rays.
The prominence of these rays implies that the small crater at the center
of the ray pattern formed comparatively recently.

This image is one in a planned set of 99. Nine different views of
Mercury were snapped in this set to create a mosaic pattern with images
in three rows and three columns. The WAC is equipped with 11 narrow-band
color filters, and each of the nine different views was acquired through
all 11 filters. This image was taken in filter 7, which is sensitive to
light near the red end of the visible spectrum (750 nm), and shows
features as small as about 6 kilometers (4 miles) in size. The MESSENGER
team is studying this previously unseen side of Mercury in detail to map
and identify new geologic features and to construct the planet's
geological history.

------------------------------------------------------------------------

Additional information and features from this first flyby will be
available online at http://messenger.jhuapl.edu/mer_flyby1.html, so
check back frequently. Following the flyby, be sure to check for the
latest released images and science results!

------------------------------------------------------------------------

MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and
Ranging) is a NASA-sponsored scientific investigation of the planet
Mercury and the first space mission designed to orbit the planet closest
to the Sun. The MESSENGER spacecraft launched on August 3, 2004, and
after flybys of Earth, Venus, and Mercury will start a yearlong study of
its target planet in March 2011. Dr. Sean C. Solomon, of the Carnegie
Institution of Washington, leads the mission as principal investigator.
The Johns Hopkins University Applied Physics Laboratory built and
operates the MESSENGER spacecraft and manages this Discovery -class
mission for NASA.
Received on Mon 28 Jan 2008 08:23:00 PM PST