Timgad Vallis

This image shows the fourth of five broad channels on Mercury for which names were recently approved (see Timgad Vallis). The valleys are named according to the theme of "abandoned cities (and towns and settlements) of antiquity" that was developed especially for these landforms.

The vallis shown in this figure is named for Timgad, a Roman colonial town in the Algerian Aurès Mountains, founded around 100 CE. The city was abandoned after an Arab invasion in the 8th century CE, before being covered by the Sahara. The city ruins were excavated in 1881. The city’s population may have been as great as 15,000. This image is a portion of the MDIS global mosaic basemap that was acquired during MESSENGER's first year in orbit.

Date Created: March 26, 2013
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
Feature Latitude Range: 59.6° N to 62.0° N
Feature Longitude Range: 114.3° E to 119.9° E
Feature Diameter: 116 km
Projection: Azimuthal equidistant

Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Paestum Vallis

This image shows the fourth of five broad channels on Mercury for which names were recently approved (see Paestum Vallis). The valleys are named according to the theme of "abandoned cities (and towns and settlements) of antiquity" that was developed especially for these landforms.

The vallis shown in this figure is named for Paestum, a major Greco-Roman city in the Campania region of Italy. The city may have been founded in the 7th century BCE, but became a Roman city in 273 BCE. Paestum is renowned for its remaining Doric temples and a number of painted tombs, which date from the 5th century BCE. This image is a portion of the MDIS global mosaic basemap that was acquired during MESSENGER's first year in orbit.

Date Created: March 26, 2013
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
Feature Latitude Range: 59.1° N to 61.0° N
Feature Longitude Range: 124.0° E to 128.5° E
Feature Diameter: 96 km
Projection: Azimuthal equidistant

Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Caral Vallis

This image shows the third of five broad channels on Mercury for which names were recently approved (see Caral Vallis). The valleys are named according to the theme of "abandoned cities (and towns and settlements) of antiquity" that was developed especially for these landforms.

The vallis shown in this figure is named for Caral-Supe, a large settlement in the Barranca province of Peru that has been dated as one of the most ancient cities of the Americas, being inhabited from ca. 2627-1977 BCE. At its peak, Caral supported a population in excess of 3,000. This image is a portion of the MDIS global mosaic basemap that was acquired during MESSENGER's first year in orbit.

Date Created: March 26, 2013
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
Feature Latitude Range: 61.8° N to 63.3° N
Feature Longitude Range: 128.3° E to 130.6° E
Feature Diameter: 64 km
Projection: Azimuthal equidistant

Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Cahokia Vallis

This image shows the second of five broad channels on Mercury for which names were recently approved (see Cahokia Vallis). The valleys are named according to the theme of "abandoned cities (and towns and settlements) of antiquity" that was developed especially for these landforms.

The vallis shown in this figure is named for Cahokia Mounds, a Native American city that was the largest urban settlement in Mississippian culture (approx. 800-1500 CE). Cahokia contained hundreds of earthen mounds that supported the city's buildings. At its peak, the city may have been home to between 6,000 and 40,000 inhabitants. This image is a portion of the MDIS global mosaic basemap that was acquired during MESSENGER's first year in orbit.

Date Created: March 26, 2013
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
Feature Latitude Range: 64.9° N to 66.7° N
Feature Longitude Range: 124.4° E to 128.5° E
Feature Diameter: 77 km
Projection: Azimuthal equidistant

Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Angkor Vallis

On April 30, 2013 the International Astronomical Union (IAU) Working Group for Planetary System Nomenclature approved new names for five broad valleys on Mercury (Angkor Vallis). These valleys have been interpreted by MESSENGER team scientists as having formed due to mechanical and thermal erosion of Mercury's surface by hot, low-viscosity, quickly-flowing lavas.

Each image this week will feature one of these five broad valleys, now termed "valles" (sing. "vallis") by the IAU. The valleys are named according to the theme of "abandoned cities (and towns and settlements) of antiquity" that was developed especially for these landforms.

The vallis shown in this figure is named for Angkor city in Cambodia, the largest pre-industrial city in the world, and once the seat of the Khmer Empire. At its peak, Angkor hosted over 1,000 temples, including the world's largest religious monument. With a suburban footprint of ca. 1,000 km², Angkor at one time may have had a population of over 1 million people. This image is a portion of the MDIS global mosaic basemap that was acquired during MESSENGER's first year in orbit.

Date Created: March 26, 2013
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
Feature Latitude Range: 56.2° N to 58.4° N
Feature Longitude Range: 112.7° E to 115.6° E
Feature Diameter: 95 km
Resolution: 250 meters/pixel
Projection: Azimuthal equidistant

Photo credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

New Names for Five Mercurian Valles

From the USGS Astrogeology Science Center:

The Working Group for Planetary System Nomenclature has approved new names for five valles on Mercury: Angkor Vallis, Cahokia Vallis, Caral Vallis, Paestum Vallis, and Timgad Vallis. For more information, see the Gazetteer of Planetary Nomenclature.