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Galaxy clusters like Abell 2744 can act as a natural cosmic lens, magnifying light from more distant, background objects through gravity. NASA's James Webb Space Telescope may be able to detect light from the first stars in the universe if they are gravitationally lensed by such clusters. (astronomy, space exploration, galaxies)

How Fast Is the Universe Expanding?

Infinite space background with silhouette of telescope. This image elements furnished by NASA.

Telescopes: Seeing Stars

Abstract vector hi speed internet technology background

History of Technology Timeline

Planet Jupiter with its moon Io at left, photographed by the Cassini orbiter during the Cassini-Huygens mission, 2000. spacecraft

7 Important Dates in Jupiter History

Centimetres vs inches, metal rulers on a white background with clipping path.

15 Questions About Units of Measurement Answered

Discover

The Colosseum, Rome, Italy. Giant amphitheatre built in Rome under the Flavian emperors. (ancient architecture; architectural ruins)

New Seven Wonders of the World

Marriage. A couple getting married during a church wedding ceremony. (religion, ceremony, bride, groom)

The Seven Sacraments of the Roman Catholic church

World Data Locator Map: Australia

Is Australia an Island?

African Americans demonstrating for voting rights in front of the White House as police and others watch, March 12, 1965. One sign reads, "We demand the right to vote everywhere." Voting Rights Act, civil rights.

Timeline of the American Civil Rights Movement

Orange basketball on black background and with low key lighting. Homepage 2010, arts and entertainment, history and society

The 10 Greatest Basketball Players of All Time

Close-up of crocodile eye; location unknown (rainforest, reptile).

What’s the Difference Between Alligators and Crocodiles?

number zero, 0 balloon

Is Zero an Even or an Odd Number?

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Topics

wing divider compass caliper length measurement tool mechanical drawing range finder odometer micrometer surveyor’s chain distance-measuring equipment hand tool radiation measurement machine tool psychological testing measurement system

Dig Deeper: More Articles That Discuss This Topic

hand tool: Compass, divider, and caliper

Key People

Georg von Reichenbach

German instrument maker

Joseph Rogers Brown

American inventor

Quiz

barometer. Antique Barometer with readout. Technology measurement, mathematics, measure atmospheric pressure

Fun Facts of Measurement & Math