[Prev][Next][Index][Thread]
(meteorobs) Is Sirius Getting Dimmer, or Moving Closer to Us?
November 24, 2002
Greetings Meteor Enthusiasts!
Although a starry topic may seem slightly "O.T.," I
think stars are so entwined with meteor observing that
they make up a necessary aspect of meteor science
rather than an unrelated subject matter set aside for
star gazers and trained telescopes. If the latter
were so, picture how difficult meteor hunting would be
if observers ignored the use of stars!
With that said, I have a starry question. In one of
my old star books (a Golden Nature Guide, copyrighted
1951) lists the bright star Sirius with a visual
magnitude of -1.58. In the Encyclopedia Britannica
(1969) they list it as -1.45 mag. However, on the
Heavens Above web site (which I frequently visit) the
star is now listed as -1.44 mag. Now Sirius, being a
relatively close star, may cause someone to conclude
that the differences in magnitude result from the
actual movement of the star--- that is, Sirius has
noticeably moved away in the past 50 or so years.
However, this may not be so if its differences in
distance are correct. In the Encyclopedia Britannica
a distance of 8.70 lightyears is given while on the
Heavens Above web site a value of 8.60 is present.
From this, the star is obviously moving closer.
Are these inconsistencies the result of past errors
and/or uncertainties, as perhaps suggested by
the information given on the Heavens Above web site?
Thank you all in advance for any clarifications or
help.
Long, glowing, and stony Geminids!
Mark Fox
Newaygo, MI USA
Coordinates: 43 deg. 27' N, 85 deg. 49' W
__________________________________________________
Do you Yahoo!?
Yahoo! Mail Plus – Powerful. Affordable. Sign up now.
http://mailplus.yahoo.com
The archive and Web site for our list is at http://www.meteorobs.org
To stop getting all email from the 'meteorobs' lists, use our Webform:
http://www.meteorobs.org/subscribe.html
Follow-Ups: