Adiri Is Equatorial Bright Albedo Feature on Titan's Anti-Saturn Side

Summary: Adiri is an equatorial bright albedo feature on Titan's anti-Saturn side that received the Cassini-Huygens Mission's Huygens probe in January 2005.

Image of equatorial bright albedo feature Adiri, obtained June 14, 2007, by Cassini spacecraft's Wide-Angle Camera (WAC), using 939 nanometer infrared light wavelength-centered spectral filter; view acquired from an approximated distance of 157,000 kilometers (98,000 miles) from Titan; image addition date 2005-01-15; image credit NASA/JPL/ESA/University of Arizona: May be used for any purpose without prior permission, via NASA JPL Photojournal

Adiri is an equatorial bright albedo feature on Titan's anti-Saturn side that has landmark status as the Jan. 14, 2005, landing site of the European Space Agency's (ESA) Huygens probe.

Adiri is centered at minus 19 degrees south latitude, 210 degrees west longitude, according to the International Astronomical Union’s (IAU) Gazetteer of Planetary Nomenclature. The Gazetteer repeats the bright albedo feature's center latitude and longitude as its northernmost and southernmost latitudes and its easternmost and westernmost longitudes, respectively.

Adiri lies in Titan's sand dune-confined equatorial belt. Radar images obtained by the Cassini spacecraft's October 2005 flyby revealed that Titan's equatorial belt, thought to host liquid oceans, actually supports sand dunes reminiscent of Earth's Arabian and Namibian deserts, according to Lori Stiles in her article, "Titan's Seas Are Sand," published May 4, 2006, on the University of Arizona News Service's website.

Titan's dunes are longitudinal, which means that their alignment reflects the prevailing wind pattern. Longitudinal dunes are considered as the most mature form of Earth's sand seas, according to planetary physicist Jason W. Barnes and five co-authors in "Production and Global Transport of Titan’s Sand Particles," published in the December 2015 issue of Planetary Science. Titan's sand seas have a global extension within the equatorial belt's 30 degrees north and 30 degrees south latitude, eastward from 80 degrees west to 130 degrees west. The interconnectedness of the geographic distribution suggests that the dunes are comprised of ancient sands. Barnes and his co-authors note Titan's apparent lack of isolated dunefields, apart from possible exceptions inside of Adiri and east of Yalaing Terra, a bright extensive land mass in the southern mid-latitudes.

Yalaing Terra resides to the west of Adiri. The bright land mass is centered at minus 19.5 degrees south latitude, 324 degrees west longitude. It registers northernmost and southernmost latitudes of minus 13 degrees south and minus 26 degrees south, respectively. It records easternmost and westernmost longitudes of 313 degrees west and 335 degrees west, respectively. Yalaing Terra's diameter spans 980 kilometers.

Within the equatorial belt, Adiri occupies a narrow corridor that evinces west-to-east transport of materials, according to NASA Jet Propulsion Laboratory (JPL) planetary scientist and organic chemist Michael J. Malaska and five co-authors in their study, "Material Flux on Titan: The Fate of Dune Materials," presented at the 46th Lunar and Planetary Science Conference, held March 16-20,2015, at The Woodlands Waterway Marriott Hotel and Convention Center in The Woodlands, Texas. The west-to-east flow occurs from Senkyo, across Belet, to Adiri.

Belet is a dark albedo feature to the west of Adiri. Belet is centered at minus 5 degrees south latitude, 255 degrees west longitude. Its center coordinates are also listed as Belet's northernmost-southernmost latitudes and easternmost-westernmost longitudes.

Senkyo lies to the west of Belet. The dark albedo feature is centered at minus 5 degrees south latitude, 320 degrees west longitude. Senkyo's center latitude and longitude are given as its northernmost-southernmost latitudes and its easternmost-westernmost longitudes, respectively.

Adiri's eastern neighbor, dark Shangri-La, shares the area of the landing site of the Cassini-Huygens mission's Huygens probe. The atmospheric entry robotic space probe, built and operated by the European Space Agency (ESA), landed Jan. 14, 2005, in terrain, near western Shangri-La, in northeastern Adiri. The NASA Science Solar System Exploration website places the probe's landing site coordinates at 10.3 degrees south latitude, 192.32 degrees west longitude.

Shangri-La is centered at minus 10 degrees south latitude, 165 degrees west longitude. The dark albedo feature's center coordinates are repeated as its northernmost-westernmost latitudes and easternmost-westernmost longitudes.

The International Astronomical Union (IAU) approved Adiri's name in 2006. The Gazetteer of Planetary Nomenclature explains the Adiri as designating the "Melanesian afterworld where life is easier than on Earth." The brightly reflective region's name conforms with the IAU's convention of selecting names for Titan's albedo features from "Sacred or enchanted places, paradise, or celestial realms from legends, myths, stories, and poems of cultures from around the world."

Composite image, obtained during Titanean descent Jan. 14, 2005, by Huygens probe's Descent Imager/Spectral Radiometer, shows "boundary between the lighter-colored uplifted terrain, marked with what appear to be drainage channels, and darker lower areas;" images acquired from an altitude of about 8 kilometers (about 5 miles); image addition date 2005-01-15; image credit NASA/JPL/ESA/University of Arizona: May be used for any purpose without prior permission, via NASA JPL Photojournal

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Dedication

This post is dedicated to the memory of our beloved blue-eyed brother, Charles, who guided the creation of the Met Opera and Astronomy posts on Earth and Space News. We memorialized our brother in "Our Beloved Blue-Eyed Brother, Charles, With Whom We Are Well Pleased," published on Earth and Space News on Thursday, Nov. 18, 2021, an anniversary of our beloved father's death.

Image credits:

Image of equatorial bright albedo feature Adiri, obtained June 14, 2007, by Cassini spacecraft's Wide-Angle Camera (WAC), using 939 nanometer infrared light wavelength-centered spectral filter; view acquired from an approximated distance of 157,000 kilometers (98,000 miles) from Titan; image addition date 2005-01-15; image credit NASA/JPL/ESA/University of Arizona: May be used for any purpose without prior permission, via NASA JPL Photojournal @ https://photojournal.jpl.nasa.gov/catalog/PIA08995

Composite image, obtained during Titanean descent Jan. 14, 2005, by Huygens probe's Descent Imager/Spectral Radiometer, shows "boundary between the lighter-colored uplifted terrain, marked with what appear to be drainage channels, and darker lower areas;" images acquired from an altitude of about 8 kilometers (about 5 miles); image addition date 2005-01-15; image credit NASA/JPL/ESA/University of Arizona: May be used for any purpose without prior permission, via NASA JPL Photojournal @ https://photojournal.jpl.nasa.gov/catalog/PIA07231

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