Smithsonian Institution
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Asset Name:
media:NASM-A20130102000_PS01

File Usage:

Not determined
There are restrictions for re-using this media. For more information, visit the Smithsonian's Terms of Use page at https://www.si.edu/Termsofuse


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Object details:

Object Name: Timer, GMT Display, Space Shuttle
Smithsonian Record ID: edanmdm:nasm_A20130102000

	Object Name
	Timer, GMT Display, Space Shuttle

	Metadata Usage
	Not determined

	Guid
	http://n2t.net/ark:/65665/nv96d1f0187-5681-4196-8b6a-e4ee171aeff0

	Data Source
	National Air and Space Museum

	Manufacturer
	DATACHRON INC

	Materials
	adhesive, aluminum, electrical wires, paper, plexiglass, stainless steel, scotch tape

	Dimensions
	3-D: 42.5 × 11.8 × 9.5cm (16 3/4 × 4 5/8 × 3 3/4 in.)

	Summary
	At orbital speed, spacecraft circle the Earth every 90 minutes, with a sunrise or sunset every 45 minutes, making it difficult to keep track of time as usual. Time in space is tracked more than one way, by reference to more than one location or standard, such as Houston time or mission elapsed time (MET). Another way is Greenwich Mean Time or Universal Time (GMT or UT), the time at the Greenwich Observatory near London, where by international agreement, each 24-hour day starts and ends. This is a GMT digital clock; it would be set to display Greenwich time in the Mission Control Center or on a spacecraft for comparison to “local” and mission elapsed time. From GMT, one can add or subtract hours to know the time elsewhere in the world. NASA sent this timer to the Museum when it was no longer needed in the Space Shuttle program.

	Country of Origin
	United States of America

	Credit Line
	Transferred from the National Aeronautics and Space Administration

	Inventory Number
	A20130102000

	Type
	EQUIPMENT-Electronics

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