alistic representation of the celestial
vault. There is, however, a small trade-off (which some users argue is not
so small). Because Google Sky uses a
latitude and longitude projection, the
stars in the original images were significantly distorted between seven and
eight degrees of both celestial poles.
Hence, these regions were replaced
with a lower-resolution view of the sky
derived from the Tycho II star catalog.
The stars in those polar regions are obviously not as sharp as the other parts of
Google Sky’s sky (they exhibit a decided
radial stretch from the pole outward),
but they are properly scaled and their
colors are based on real color data.
Like Google Earth, Google Sky utilizes Keyhole Markup Language (KML),
which is an XML-based language for
displaying geographic data and visualizations for Web-based 3D browsers. In
this case, KML files display not mountains and cities, but celestial objects as
well as annotated data files. Users can
add their own content by converting it
into a KML file and posting it at either
Google Sky or on the Web so that others can add it, if they choose. One such
example is an orrery that shows the
positions of the planets in the solar
system with respect to each other on a
“i’m coming across
this problem that
the kids are way
ahead of teachers,”
says carol christian.
in context with their surroundings in
the immensity of space. For example,
when you zoom in on the region of sky
known as Hubble Ultra Deep Field,
you’ll discover it is just one-tenth
the diameter of the full Moon, small
enough to cover with a pencil tip held
at arm’s length. But when you follow
the clickable links, you’ll discover this
tiny bit of celestial real estate contains
more than 10,000 galaxies.
Lior Ron, a product manager for
Google Sky, says the program encourages users to see Earth in perspective
with the vastness of the universe. “We
hope that Google Sky will bring about
a fundamental change in the way we
perceive our place in the universe, just
as Google Earth changed how we look
at our planet,” he says. “A number of
[theorists] have talked to us about how
looking at things like the IRAS [infrared
astronomical satellite] infrared map
in the Web version of Google Sky really
brought a physical reality to their mental model of the sky that they hadn’t had
previously,” says Ron.
One of the most fascinating aspects of WWT and Google Sky is how
they allow you to view celestial objects
field of Dreams
The advent of these virtual telescope
programs is being celebrated by astronomers, but as Djorgovski notes, measuring their impact on education is tricky.
Carol Christian, an astronomer at the
Space Telescope Science Institute,
home of the Hubble Space Telescope,
agrees. “It’s something that’s going to
take years,” she says. “This isn’t something you can do in a couple of months.
Right now it’s a field of dreams. We built
it. Will they come?”
Christian believes the key to Google
Sky’s success will be innovative educators. “I’m coming across this problem
that the kids are way ahead of teachers,”
she says. “We need to get teachers. . . to
understand that the student of the future and the worker of the future needs
to be facile with finding information,
analyzing it, applying critical thinking,
making decisions, and finding the data
they need to answer a question.”
To date, both the WWT and Google
Sky claim millions of active users. If
these numbers are any indication, both
applications will soon be an essential
part of the science classroom and museum, as well as a powerful tool that
will enable researchers to access, publish, and update data in context with
the very universe they study. The virtual
telescope is a field of dreams with unlimited possibilities, all of which will
be explored and augmented by users in
ways we can only speculate about now.
In the not-too-distant future, computer scientists may look back on the rise
of applications such as the WWT and
Google Sky as forerunners of the much
ballyhooed Web 3.0 era, which would
be fitting since it promises to be light-years ahead of today’s Internet.
a view of the andromeda Galaxy, a spiral galaxy located more than two million light-years
away, as it appears in Google sky.
based in Derwood, mD, Jeff Kanipe is the author of The
Cosmic Connection: How Astronomical Events Impact
Life on Earth.