The first use of

3D laser scanning Lidar (, also LIDAR, or LiDAR; sometimes LADAR) is a method for determining ranges (variable distance) by targeting an object or a surface with a laser and measuring the time for the reflected light to return to the receiver. It can also be ...

at Stonehenge was of the

Bronze Age The Bronze Age is a historic period, lasting approximately from 3300 BC to 1200 BC, characterized by the use of bronze, the presence of writing in some areas, and other early features of urban civilization. The Bronze Age is the second prin ...

dagger and axes inscribed on the sarsens, which was undertaken in 2002 by a team from

Wessex Archaeology Wessex Archaeology is a British company that provides archaeological and heritage services, as well as being an educational charity. Apart from advice and consultancy, it also does fieldwork and publishes research on the sites it surveys. The comp ...

and Archaeoptics. They used a

Minolta was a Japanese manufacturer of cameras, camera accessories, photocopiers, fax machines, and laser printers. Minolta Co., Ltd., which is also known simply as Minolta, was founded in Osaka, Japan, in 1928 as . It made the first integrated aut ...

Vivid 900 scanner to analyse and record surfaces of the prehistoric and post-medieval

carvings Carving is the act of using tools to shape something from a material by scraping away portions of that material. The technique can be applied to any material that is solid enough to hold a form even when pieces have been removed from it, and ...

. The

carvings of a

dagger A dagger is a fighting knife with a very sharp point and usually two sharp edges, typically designed or capable of being used as a thrusting or stabbing weapon.State v. Martin, 633 S.W.2d 80 (Mo. 1982): This is the dictionary or popular-use de ...

and an axehead were first discovered by archaeologist Richard J. C. Atkinson in 1953 on stone number 53, one of the imposing sarsen

trilithon A trilithon or trilith is a structure consisting of two large vertical stones (posts) supporting a third stone set horizontally across the top (lintel). It is commonly used in the context of megalithic monuments. The most famous trilithons ar ...

s. A contemporary survey in 1956 by Robert Newall revealed that the total number of axes on this stone totalled 14, all on the same face of the stone, looking inwards to the centre of the stone circle. Typologically, the axes have a Middle

date. The surface of stone 53 containing

carvings was laser scanned at a resolution of 0.5mm, resulting in hundreds of thousands of individual 3D measurements known as a

point cloud Point or points may refer to: Places * Point, Lewis, a peninsula in the Outer Hebrides, Scotland * Point, Texas, a city in Rains County, Texas, United States * Point, the NE tip and a ferry terminal of Lismore, Inner Hebrides, Scotland * Poin ...

. These data were then processed into a meshed 3D solid model for analysis using custom software written by Archaeoptics called ''Demon3D''. The team pioneered some visualisation techniques to enhance the outlines of the known carvings. During this process, the faint outline of two previously unknown axes was spotted in an animation, separate from the carvings recorded by Newall. Subsequent enhancement of the data confirmed that the shapes were of

flange A flange is a protruded ridge, lip or rim, either external or internal, that serves to increase strength (as the flange of an iron beam such as an I-beam or a T-beam); for easy attachment/transfer of contact force with another object (as the f ...

d axes, similar in shape to those clearly visible, but either badly

eroded Erosion is the action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material from one location on the Earth's crust, and then transports it to another location where it is deposited. Erosion is disti ...

, or were originally carved much shallower than their counterparts. The larger of the two carvings differs slightly from the other axes in that it has two 'lugs' along its shaft, and others have interpreted that it could represent either an axe, a mushroom, or a ram's skull. The results of these investigations were published in an article entitled "The Stonehenge Laser Show" in the November 2003 edition of British Archaeology. In 2011 English Heritage commissioned a full laser scan of the visible faces of all stones as Stonehenge in high resolution (sub-millimetre), as well as a lower resolution scan of the ground in the area known as the "Stonehenge Triangle".

References

External links

*https://web.archive.org/web/20051225111736/http://www.stonehengelaserscan.org/ {{Stonehenge Stonehenge