Speed of Light

A constant of Nature. This speed is precisely 299,792,458 meters per second, or roughly 670,616,629 miles per hour. One of the most unusual discoveries of science has been the fact that all Observers measure light as moving at exactly this speed, even if those observers are moving relative to each other. This fact is one of the basic ingredients in Einstein's Special Theory of Relativity.

Four Areas of Science


Time writes no wrinkle
on thine azure brow,
Such as creation's dawn
beheld, thou rollest now.

Lord Byron's Childe Harold's Pilgrimage,
Canto IV,
Stanza 182

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About SXS

The SXS project is a collaborative research effort involving multiple institutions. Our goal is the simulation of black holes and other extreme spacetimes to gain a better understanding of Relativity, and the physics of exotic objects in the distant cosmos.

The SXS project is supported by Canada Research Chairs, CFI, CIfAR, Compute Canada, Max Planck Society, NASA, NSERC, the NSF, Ontario MEDI, the Sherman Fairchild Foundation, and XSEDE.

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