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Summary
DescriptionDeep Space Atomic Clock engineering sample.jpg
English: A laboratory representation of the Deep Space Atomic Clock, with a quarter alongside the unit for size comparison, and without the electronics required for operation. It also contains laboratory components, including a metal frame, instead of flight hardware. At just under 0.2 cubic feet and weighing about 7 pounds, the clock is smaller, lighter and more stable than any other atomic clock flown in space.
Source
Deep Space Atomic Clock engineering prototype.jpg
Author
NASA
This image has currency in it to indicate scale.
Using coins for scale is discouraged as it will require people unfamiliar with them to look up the dimensions or guess, both of which defeat the purpose of the object in the first place. Coins can also reinforce a geographical bias, and some coins' designs are copyrighted.
Ideally, a photograph should include a ruler with the subject (example) or an added scale marking.
SI ("metric") units are the most commonly used worldwide (see meter and centimeter).
The NASA website hosts a large number of images from the Soviet/Russian space agency, and other non-American space agencies. These are not necessarily in the public domain.
The SOHO (ESA & NASA) joint project implies that all materials created by its probe are copyrighted and require permission for commercial non-educational use. [2]
{{Information |description ={{en|1=A laboratory representation of the Deep Space Atomic Clock, with a quarter alongside the unit for size comparison, and without the electronics required for operation. It also contains laboratory components, including a metal frame, instead of flight hardware. At just under 0.2 cubic feet and weighing about 7 pounds, the clock is smaller, lighter and more stable than any other atomic clock flown in space.}} |date = |source =Deep Space Atomic...