NASA Dawn Reveals Recent Changes in Ceres’ Surface

Observations of
Ceres have detected recent variations in its
surface, revealing that the only
dwarf planet in the inner
solar system is a dynamic body that continues to
evolve and

NASA’s Dawn
mission has found recently exposed deposits that
give us new information on the
materials in the crust and how
they are changing, according to two papers
published March 14
in Science Advances that document the new findings.

obtained by the visible and infrared mapping
spectrometer (VIR) on the Dawn
spacecraft previously found
water ice in a dozen sites on Ceres. The new study revealed
the abundance of ice on the northern wall of Juling Crater, a
crater 12 miles
(20 kilometers) in diameter. The new
observations, conducted from April through
October 2016, show
an increase in the amount of ice on the crater wall.

TRAPPIST-1 This view from NASA’s Dawn mission shows
Ceres’ tallest mountain, Ahuna Mons, 2.5 miles (4 kilometers)
high and 11 miles (17 kilometers) wide. This is one of the few
sites on Ceres at which a significant amount of sodium
carbonate has been found, shown in green and red colors in the
lower right image. Credit:

Full image and caption

“This is the
first direct detection of change on the surface
of Ceres,” said Andrea Raponi
of the Institute of Astrophysics
and Planetary Science in Rome.

Raponi led the
new study, which found changes in the amount of
ice exposed on the dwarf planet.
“The combination of Ceres
moving closer to the sun in its orbit, along with seasonal
change, triggers the release of water vapor from the
subsurface, which then
condenses on the cold crater wall. This
causes an increase in the amount of
exposed ice. The warming
might also cause landslides on the crater walls that
fresh ice patches.”

By combining
chemical, geological and geophysical
observations, the Dawn mission is
producing a comprehensive
view of Ceres. Previous data had shown Ceres has a
crust about
25 miles (40 kilometers) thick and rich in water, salts and,
possibly, organics.

In a second study,
VIR observations also reveal new
information about the variability of Ceres’
crust, and suggest
recent surface changes, in the form of newly exposed

Dawn previously
found carbonates, common on the planet’s
surface, that formed within an ocean.
Sodium carbonates, for
example, dominate the bright regions in Occator Crater,
material of similar composition has been found at Oxo Crater
and Ahuna Mons.

This study, led
by Giacomo Carrozzo of the Institute of
Astrophysics and Planetary Science,
identified 12 sites rich
in sodium carbonates and examined in detail several
areas of a
few square miles that show where water is present as part of
carbonate structure. The study marks the first time
hydrated carbonate has been
found on the surface of Ceres, or
any other planetary body besides Earth,
giving us new
information about the dwarf planet’s chemical evolution.

Water ice is
not stable on the surface of Ceres over long time
periods unless it is hidden
in shadows, as in the case of
Juling. Similarly, hydrated carbonate would
although over a longer timescale of a few million years.

“This implies that the sites rich in hydrated carbonates
been exposed due to recent activity on the surface,” Carrozzo

The great diversity of material,
ice and carbonates, exposed
via impacts, landslides and cryovolcanism suggests Ceres’
crust is not uniform in composition. These heterogeneities were
either produced
during the freezing of Ceres’ original ocean –
which formed the crust – or
later on as a consequence of large
impacts or cryovolcanic intrusions.

“Changes in the
abundance of water ice on a short timescale,
as well as the presence of
hydrated sodium carbonates, are
further evidence that Ceres is a geologically
and chemically
active body,” said Cristina De Sanctis, VIR team leader at the
Institute of Astrophysics and Planetary Science.

The Dawn mission is managed by JPL for NASA’s Science Mission
Directorate in Washington. Dawn is a project of the
directorate’s Discovery
Program, managed by NASA’s Marshall
Space Flight Center in Huntsville, Alabama.
JPL is responsible
for overall Dawn mission science. Orbital ATK Inc., in
Virginia, designed and built the spacecraft. The German
Center, Max Planck Institute for Solar System
Research, Italian Space Agency
and Italian National
Astrophysical Institute are international partners on the
mission team.

For a complete list of mission participants, visit:

More information about Dawn is available at the following

News Media Contact

Gretchen McCartney
Jet Propulsion Laboratory, Pasadena, Calif.


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