Barnard's Star moves against the background of more distant stars faster than any other star that we know about.
It moves at the amazing speed of 10.4 "arc/year, which corresponds to a lunar diamter in only 173 years. For stars, that's fast!
A typical amateur's CCD and telescope system affords a resolution of 1"arc (my present system has a resolution of 0.64 "arc per pixel). Therefore, it is theoretically possible to use CCD images to measure a star's location with respect to other stars with an accuracy that should enable Barnard's Star's motion in only a month or two. This web page will record my attempt to produce a "movie" of Barnard's Star moving. Barnard's Star is at coordinates 17:57:48.0, +04:42:56 (equinox 2000.0, 2007.09.28).
The folowing movies won't show a large region of the sky, due to the need to keep file size small, but it will be good to see the region where Barnard's Star has been during the past 50 years. (A screen resolution of 1280x1024 will display the following images in one view).
Figure 1. Region of sky where Barnard's Star has been during
the past 50 years. The dimensions of this image are 27 x 14 'arc. The
full moon has a diameter that averages about 30 'arc, so this image has
a width approximately equal to that of the full moon. North is "up."
Barnard's motion has a direction that is 5 degrees clockwise from north
(i.e.,
position angle = 5 degrees). Barnard's Star has a magnitude of 9.6. The
faintest stars are 18th magnitude. Sum of images taken 2002.04.21,
2002.05.30
and 2002.06.14. [Meade LX200 10-inch SCT, f/6.3, SBIG ST-8E CCD,
TT CFW, unfiltered, Santa Barbara, CA residence]
Figure 2. Zoom to FOV = 10.9x7.1 'arc with 4 images overlain showing motion during a 5-year interval.
Figure 4. 4-frame "movie" of Barnard's Star
motion. Northward (upward) motion is captured by a small-area
crop for four dates: 2002.04.21, 2004.06.14, 2005.09.29 and 2007.09.28.
Digital development was used to reduce saturation effects. Image
dimensions are 10.9 x 7.1 'arc. Barnard's Star moved 56.58 "arc during
this 5.439-year interval, which corresponds to a speed of 10.402
"arc/year. The movement's position angle is 354.8 degrees.
Differences in image sharpness are due
to the change of telescope (from a Meade 10-inch to a Celestron 14-inch
to a Meade 14-inch),
atmospheric seeing changes, differences in telescope collimation,
differences
in observing site, and gradual improvements in observing technique and
analysis
procedure. [2005 image is from 14 5-second images, median combined,
taken with Celestron 14-inch, SBIG AO-7 image stabilizer, V-filter, ST-8XE
CCD; 2007 image is from a median combine of 14 1-second exposures; Hereford, AZ, 4656 feet ASL]
Figure 3. Animation for a 5-year span, 2002 to 2007. Note
the improved image sharpenss for the 2007 image (seeing was ~2.1 "arc;
Meade LX200GPS, 2007.06.13, HAO).
You may learn more about Barnard's Star at Frommer.and other links on that web page.
WebMaster: Bruce L. Gary. Nothing on this web page is copyrighted. This site opened: May 26, 2002.05.26. Last Update: 2007 September 28