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Astronomical Data on Magnetic Tape


A circular plastic cartridge with a clear lid covering one face. A reel of magnetic tape is visible through the clear lid. The cartridge has a hole in the centre. The clear face of the cartridge has a label marked in blue pen.

Accession Number: 2019.ast.201

Alternative Name:

Primary Materials: Plastic.


A paper label at the top surface reads:
“G13005 SCAN data// Runaway Stars// May 20/21, ’81 -> Aug 17/18, ’81”

A printed label around the outer surface of the central hole of the case reads:

A second smaller label reads: “6250// ALPHA PHI”

A label along the rim of the case is marked in blue ink:

A printed label on the bottom surface of the case reads:
“LOT NO. 27338 1”

Dimensions (cm): Max diameter = 28.8; Height = 2.3.


This tape is a form of data storage media. It is an IBM System/360 9 track tape magnetic storage tape. It stores information at 6250 characters per inch of tape.

This tape has been used to store astronomical spectroscopic data produced at the David Dunlap Observatory (DDO) and the Dominion Astrophysical Observatory (DAO).


Very Good: The case is dirty in places and slightly scuffed.

The integrity of the data is unknown. However, according to Department of Astronomy & Astrophysics Professor Emeritus John Percy, in an interview conducted on March 11, 2021, it is very likely that the tape has degraded, and the data lost,

Associated Instruments:


Control Data Corporation, Bloomington, Minnesota; David Dunlap Observatory

Date of Manufacture: Early 1980s


This tape contains spectroscopic data on 36 high-velocity stars gathered by Douglas Gies and C. T. Bolton at the David Dunlap Observatory (DDO) in Richmond Hill, Ontario, as well the Dominion Astrophysical Observatory (DAO) in Vancouver. The data was recorded onto glass slides and those images digitized onto magnetic tape.

This example of stored data is was provided by Lee Robbins, Librarian at the University of Toronto Department of Astronomy & Astrophysics, to the HPS401H1 “Scientific Artifacts” class taught in 2019 by Dr. Erich Weidenhammer at the Institute for the History and Philosophy of Science and Technology (IHPST). It was researched by student Brian Li, whose research report is cited below.

Additional Information and References:

Gies, D. R., & Bolton, C. T. (1986). The Binary Frequency and Origin of the OB Runaway Stars. <i>The Astrophysical Journal Supplement Series</i>, 419-454.,

Li, Brian (2019), <i>Artifact Research Guide: Data on Magnetic Tape.</i> HPS401H1 Final Assignment.

Historical Notes: