An aerial sculpture suspended above a walkway in Boston, USA, is sure to catch the eye until October this year.

Until October 2015, a massive aerial sculpture spanning 180m will remain suspended 111m above the Rose Kennedy Greenway in Boston, USA, a pedestrian walkway through a stretch of contemporary parks.

Having been installed at the beginning of May, the artwork was fabricated out of more than 160km of rope and contains over half a million knots to create an interconnected mesh, weighing approximately one ton.

Despite its size and total weight the structure floats lightly in the wind, each element affecting the others, creating fluent movements. The type of rope that was used is incredibly lightweight, which made it possible to attach it to three surrounding buildings and lends it its lacy appearance against this backdrop of hard-edged skyscrapers. However, the rope fibres are about 15 times as strong as steel, which enables the sculpture to exert a force of over 100 tons.

The visual effect
During the day, the aerial sculpture blends in with the sky and casts shadows on the ground to remind pedestrians to look upwards. At night, it is lit up with 44 dynamic LED fixtures. Sensors around the site monitor the movements of the fibres as well as tension, and this data then directs the colour of the light projected onto the sculpture’s surface.

The design
Designed by Janet Echelman as the signature contemporary art installation of the Greenway Conservancy’s Public Art Programme, it is entitled “As if it was already here” and is meant to represent the history of the location where it is exhibited. It comprise three holes which remind of the Tri-Mountain that was demolished in the 18th century, while the different colour banding symbolises six traffic lanes that were there before the space was reclaimed as an urban pedestrian area.

The design was modelled in a unique software programme jointly developed by Studio Echelman and Autodesk. A custom plug-in tool allows easy investigation of net densities, shape and scale, as well as simulating the effects of gravity and wind.

The installation
It took almost a full day and about 50 people to put up this huge aerial sculpture, using six cranes. Special care was taken, with the help of a bio-engineering firm, to ensure that no birds are endangered by the installation during its display. The nets are made of thicker rope with wider openings than nets used to capture birds or other animals, and are not unlike naturally occurring plant growth, which birds are well adapted to avoid.

Full thanks and acknowledgement are given to www.echelman.com and www.rosekennedygreenway.org, which were used as sources for this article.

Quick facts:
•    Over 160km of rope was used.
•    Over half a million knots were made: 542 500.
•    The sculpture weighs about one ton.
•    Highest point of attachment: 111m.
•    Longest span: 180m.
•    The sculpture can exert a force of over 100 tons.