Search results
Results from the WOW.Com Content Network
[5] [6] As with other albedo features on Mars, the name Cydonia was drawn from classical antiquity, in this case from Kydonia (Ancient Greek: Κυδωνία; Latin: Cydonia), a historic polis (city state) on the island of Crete. [7] Cydonia contains the "Face on Mars", located about halfway between the craters Arandas and Bamberg. [4]
In planetary geology, an albedo feature is a large area on the surface of a planet (or other Solar System body) which shows a contrast in brightness or darkness with adjacent areas. Historically, albedo features were the first (and usually only) features to be seen and named on Mars and Mercury .
Albedo (/ æ l ˈ b iː d oʊ / al-BEE-doh; from Latin albedo 'whiteness') is the fraction of sunlight that is diffusely reflected by a body. It is measured on a scale from 0 (corresponding to a black body that absorbs all incident radiation) to 1 (corresponding to a body that reflects all incident radiation).
The "Face on Mars", of great interest to the general public, is located near 40.8 degrees north and 9.6 degrees west, in an area called Cydonia. When Mars Global Surveyor examined it with high resolution, the face turned out to just be an eroded mesa. [8] Mare Acidalium contains the Kasei Valles system of canyons.
The fraction of sunlight reflected is a quantity called albedo, which ranges from 0 for a body that reflects no sunlight to 1.0 for a body that reflects all sunlight. Different parts of a planet's surface (and atmosphere) have different albedo values depending on the chemical and physical nature of the surface.
The first astronomer to name Martian albedo features systematically was Richard A. Proctor, who in 1867 created a map (based in part on the observations of William Rutter Dawes) in which several features were given the names of astronomers who had been involved in mapping Mars. In some cases, the same names were used for multiple features.
Albedo map shows the measured difference in surface reflectivity from the surface of a celestial body. Atlas is a special collection of images of a celestial body surface. The images may be from either ground-based or spacecraft sources. Usually a single scale or set of scales is used throughout the atlas.
Coloring of the base map indicates relative elevations, based on data from the Mars Orbiter Laser Altimeter on NASA's Mars Global Surveyor. Whites and browns indicate the highest elevations ( +12 to +8 km ); followed by pinks and reds ( +8 to +3 km ); yellow is 0 km ; greens and blues are lower elevations (down to −8 km ).