Proper Motion of Selected Stars within the Rosette Nebula
Region (over 50 years)
This is a two frame movie comparing my recent image
of the Rosette Nebula with that of the POSS1 sky survey
from the mid 1950's (a useful article describing the POSS may be found here).
All stars are moving at fast speeds relative to one another, but it is
difficult to appreciate this motion given the vast distances that
separate individual stars. Such motion is called "proper motion"
(to distinguish it from sources of "improper motion" such as parallax
and precession) and is easy to appreciate for stars that are quite
close to earth, such as Barnard's star, which moves at a speed of
approximately 10.3 arcseconds per year. For stars that are
further away, it may take many decades or even millenia to appreciate
this motion. For instance, Edmund Halley first discovered proper
motion of Sirius, Arcturus, and Aldebaran in 1718 by comparing his
coordinates with those of Hipparchus obtained almost 2,000 years
earlier! The above motion of 5 selected stars is
after 50 years, although it is still quite small by Barnard's star
standards. Please click on the above links for a close up of
individual stars and additional details. Proper
stars will eventually cause the constellations
to lose their familiar shapes.
here for the original image and photographic details.
note: Graphics on this website may not be reproduced without
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