RELEASE: 00-220

As the Russian service module “Zvezda” nears its July 25 rendezvous
with the International Space Station, stargazers and space enthusiasts can
track the progress of construction on the ambitious space research facility.

And they can do it with the naked eye.

A new Web site developed at NASA’s Marshall Space Flight Center in
Huntsville, Ala., is making it easy and exciting for enthusiasts across the
country and around the world to catch a glimpse of the orbiting facility.

The “Liftoff to Space Exploration” Web site at:
lets users identify the orbiting Space Station — and determine in advance
when it will pass over their hometowns. The site relies on a sophisticated,
Java-based program called J-Pass, developed by Patrick Meyer, a data systems
engineer at the Marshall Center.

J-Pass displays user-friendly tracking information provided by the
North American Aerospace Defense Command (NORAD). It permits site visitors
to track not only the International Space Station, but also the Russian
station Mir, Space Shuttle missions, and other objects in Earth orbit.

Orbiting at more than 200 miles above the Earth, the Space Station
is quickly growing into one of the brightest permanent fixtures in the night
sky. Currently consisting of the American connecting module “Unity” and the
Russian control module “Zarya,” the Station circles the planet approximately
16 times per day, traveling at 17,500 mph in an orbit varying 208 to 285
miles from Earth.

Because it reflects sunlight down to Earth, the Space Station often
looks like a slow-moving star as it crosses the sky. That deceptive
appearance can fool a casual viewer. But it also makes sighting the Station
easier if one knows when and where to look for it.

The best time to catch a glimpse of the Space Station is near dawn
or dusk, when the viewer is in near-darkness and the passing Station
continues to reflect light from the rising or setting Sun.

The J-Pass program provides users with optimal visibility times for
their locations. Detailed sky charts, including positions of visible
planets and bright stars to use as reference points, can be printed for
outdoor use. The program even estimates the expected brightness of the
Space Station as it passes overhead.

Viewed under optimal conditions, the Station has been observed to
appear nearly as bright as the star Sirius. When construction is complete,
estimates suggest the 470-ton “city in space” will be brighter than the
planet Venus.

Access to J-Pass requires a Java-enabled browser, such as recent
versions of Netscape Navigator or Microsoft Internet Explorer. For viewers
without a Java-enabled browser, the Web site includes an automated mailing
list option. Subscribers to the list — more than 8,000 to date — are
notified by e-mail of upcoming satellite passes.

The International Space Station is a cooperative endeavor by the
United States and 15 other nations. It is the largest international space
construction effort in history.