Erik Gregersen
Encyclopædia Britannica Editor
Connect with Erik Gregersen
Erik Gregersen is a senior editor at Encyclopaedia Britannica, specializing in the physical sciences and technology. Before joining Britannica in 2007, he worked at the University of Chicago Press on the Astrophysical Journal. Prior to that, he worked at McMaster University on the ODIN radio astronomy satellite project.
Primary Contributions (415)
Leap second, a second added to the clock to resolve discrepancies between Coordinated Universal Time (UTC), which is measured by atomic clocks, and astronomical time (UT1), as measured by Earth’s rotation. Leap seconds are added to keep the difference between UTC and UT1 at less than 0.9 second.…
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Chemistry: Fact or Fiction?
Quantum Mechanics
Extrasolar Planets
Space Records
Sumo: Fact or Fiction?
Influential Computer Programming Languages
5 Weird Facts About Venus
7 Important Dates in Mercury History
5 Things People See in the Moon
5 Mysteries of Jupiter That Juno Might Solve
6 Amazing Facts About Gravitational Waves and LIGO
10 Important Dates in Mars History
10 Important Dates in Pluto History
7 Celebrities You Didn’t Know Were Inventors
Behind the Scenes: 9 Infamous Mobsters of the Real Boardwalk Empire
Rediscovered Artists: 6 Big Names That Time Almost Forgot
5 Unforgettable Moments in the History of Spaceflight and Space Exploration
