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How far from Earth is Cassiopeia A?

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Detail of the Cygnus Loop.This nebula is the product of a supernova explosion; in this section, the blast wave has encountered an area of dense interstellar gas, creating turbulence in the wave and causing it to glow. The picture is a composite of three images taken by the Hubble Space Telescope. — Supernova remnant Detail of the Cygnus Loop.
This nebula is the product of a supernova explosion; in this section, the blast wave has encountered an area of dense interstellar gas, creating turbulence in the wave and causing it to glow. The picture is a composite of three images taken by the Hubble Space Telescope.

Cassiopeia A is located approximately 11,000 light-years from Earth.1