Context

The first ever digital, unified, global, geological map of the moon was released virtually by the  United States Geological Survey (USGS), National Aeronautics and Space Administration (NASA) and the Lunar Planetary Institute.

About

• Called the ‘Unified Geologic Map of the Moon’, it is a ‘seamless, globally consistent, 1:5,000,000-scale geologic map’.
• The moon the closest cosmic body to Earth through which space discovery can be attempted and documented has always piqued the interest of humanity.
• The researchers built on the original digital renovation of the six 1:5,000,000-scale lunar geologic maps comprising of the near, central far, east, west, north and south sides that was released in 2013.
• The final map consists of 43 geologic units across the entire lunar surface, broken down into groups based on characteristics like materials of craters, basins, terra, plains and volcanic units.
• Data from recent satellite missions to the moon and resources data from NASA’s Apollo Missions were used to come up with the map.
• This version of the map is a digital release only available in GIS and PDF formats. The map can be downloaded from the Unified Geologic Map of the Moon website.

The mapping process:                                                                       

• To make the digital map a reality, scientists used information gathered from six Apollo-days regional maps, interpolated with more recent satellite missions to lunar space.
• The existing historical maps were redrawn to line them up with more modern datasets. This preserved previous observations and geological interpretations.
• In addition to merging new and old data, USGS researchers also worked on a unified description of stratigraphy — also called rock layers — on the surface of the moon.
• This helped resolve issues from previous maps, when rock names, ages, and descriptions were periodically inconsistent.

The moon profile:

• The Moon, otherwise known as Luna, is the only natural satellite of Earth.
• It was created 4.6 billion years ago, and it is widely accepted that it was created when Earth collided with a planet-sized object called Theia.

It’s the fifth-largest moon in our solar system and is the second brightest object in the sky (after the Sun).

Orbital characteristics

• Average distance from Earth: 238,855 miles (384,400 km)
• Perigee (closest approach to Earth): 225,700 miles (363,300 km)
• Apogee (farthest distance from Earth): 252,000 miles (405,500 km)
• Orbit circumference: 1,499,618.58 miles (2,413,402 km)
• Mean orbit velocity:2,287 mph (3,680.5 km/h)

Moon’s South Pole:

• The moon’s South Pole is especially interesting because the area is much larger than the North Pole and there could be possibility of presence of water in these permanently shadowed areas.

Further, the South Pole region also contains the fossil record of the early Solar System.

Missions targeting Lunar South Pole: The Indian Space Research Organisation (ISRO) ‘Chandrayaan 2’, is an active mission that targets the Lunar South Pole for exploration. Like Chandrayan, other moon missions like the Artemis (human spaceflight programme), that is a crewed exploration programme of NASA, plan to send humans to the Lunar South Pole by 2024 and in due course of time, establish a permanent presence on the moon. These present and future moon missions’ success can be further helped by the digital map of the moon.

Significance of this new map:

• This map provides vital information for new scientific studies by connecting the exploration of specific sites on the moon with the rest of the lunar surface.
• It has very practical implications. The geology of the moon is very important for planning future missions and establishing scientific objectives.
• It will serve as a blueprint for future human missions and a source of research and analysis for the educators and the general public interested in lunar geology.