by Kathleen Robertson, Institute for Astronomy Librarian
What was that bright light moving overhead? If it was moving too fast to be
a planet, and was too high for an airplane, it may have been the International
Space Station (ISS) or the Hubble Space Telescope (HST). The space shuttle,
various satellites, and space junk can also catch the observer's eye. How can
you supplement your star chart to identify more fleeting phenomenon? A number
of Web sites offer excellent tools for tracking these objects.
Heavens Above, www.heavens-above.com,
provides tools to track ISS, HST, and Iridium and other satellites. The site
works from coordinates supplied by the user, but a huge list of location coordinates
is available. As an anonymous user, click on "Select your location," then select
your country and enter your city's name in the search block. When you select
your location from the results list (click on Neighbors for other nearby locales),
you are taken to a page with those coordinates entered. You can click on ISS,
HST, and other objects. A ten-day period will be searched. Each result screen
includes links to information on the size, purpose, and launch date of the object.
If the object will be visible during that period, a table displays start and
end times for viewing and maximum altitude. Be sure to follow the links from
the sighting date to the sky chart showing pass details, and to a ground track
plot that helps you orient yourself to the object's path.
The NASA Human Space Flight site offers links to the Shuttle and the ISS.
A list of cities is provided for a quick check of what might be currently visible.
(Cities are listed across the columns, rather than down. Honolulu is there.)
The page on sighting help is a useful starting point for learning how to read
the pass data in the tables and provides an orientation to the directional and
elevation information needed for successful spotting.
This is a rich site that rewards a prolonged browse.
If your star chart and these links whet your appetite for more news of sky
events, come to the IfA Library's Electronic Ephemeris and explore the tracks
of comets, future eclipses, and other intriguing discoveries.