Light Echoes | Mt Stromlo Observatory 2024 | Sydney Observatory 2023

Light Echoes is an installation developed by Anna Raupach and Diana Chester that celebrates the women ‘star measurers’ who worked on the Astrographic Catalogue in the 19th and 20th century. A workforce of women were employed to work as human computers on the Astrographic Catalogue at Sydney, Melbourne and Perth observatories between 1890 and 1964. Their work in measuring the positions of stars was a major contribution to this international scientific endeavour and is under-acknowledged in published documentation.

Light Echoes transcribes signatures found in hundreds of logbooks held in the MAAS collection, at Sydney Observatory, and in the NSW Archives into an augmented reality sky space. The research for this work involved cross-checking data to match up the signatures to the corresponding photographic plates and using this new data to build a virtual sky map that embeds the women’s re-animated hand-drawn signatures into the astronomical coordinates of the stars they mapped.

The soundscape creates spatial sonification of the stars and planets in the night sky, based on data decoded by the “human computers” from astrographic plates created at Sydney Observatory from 1890-1927. The process of data sonification is achieved by taking particular data points of the number of stars and planets at a particular declination (the angular distance of a point north or south of the celestial equator) in the night sky in a particular year, and developing a soundscape for each declination over a particular part of the earth. The data points become the source materials to create these sonifications using custom software that converts parsed data from the log books into MIDI information. The recordings from each declination are then woven together into a soundscape and the sounds, now representing stars, are spatialised across the celestial sphere in a 360 degree fashion like in a planetarium. This is accomplished by placing certain stars closer and others further, some moving around the listener, while others remain static but become louder of softer over time.

This work was born out of a Powerhouse Research Fellowship at the Museum of Arts and Applied Sciences in Sydney, and benefitted from the support of the Sydney Observatory and the NSW archives.

Installation Photos