281 is an H II region in the constellation of Cassiopeia and part of
the Perseus Spiral Arm. It includes the open cluster IC 1590, the
multiple star HD 5005, and several Bok globules. Colloquially, NGC 281
is also known as the Pacman Nebula for its resemblance to the video game
The nebula was discovered in August 1883 by E. E.
Barnard, who described it as "a large faint nebula, very diffuse." The
multiple star HD 5005, also called \beta1, was discovered by S. W.
Burnham. It consists of an 8th-magnitude primary with four companions at
distances between 1.4 and 15.7 seconds of arc. There has been no
appreciable change in this quintuple system since the first measurements
were made in 1875.
The nebula is visible in amateur telescopes
from dark sky locations. In his book Deep Sky Wonders, Walter Scott
Houston describes the appearance of the nebula in small telescopes.
There was a faint glow in the immediate vicinity of the multiple star,
with an occasional impression of a much larger nebulosity...Its surface
brightness was much less than that of M33 in Triangulum or NGC 205, the
distant companion of the Andromeda galaxy.
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