AMERICAN astronomers are designing a cheap, automated telescope for
use in schools and colleges. The telescope’s mirror will measure only 10
to 20 centimetres in diameter. The developers, from the Harvard-Smithsonian
Center for Astrophysics in Cambridge, Massachusetts, hope that within the
next five years they will have produced a telescope costing no more than
$5000.
Many of the telescopes now used in schools require continual adjustment
to track objects. Most are also designed to be used only at night; and usually,
only one student can use the telescope at a time. A microcomputer will point
the new telescope at stars and track their motion across the sky. The optics
inside will focus light onto a highly sensitive detector, called a charge-coupled
device, which will send the data to another microcomputer which processes
the image.
The human eye retains an image for only about 1/15th of a second, but
the electronic detectors in the telescope can accumulate light energy over
a much longer period, so they can detect much fainter objects.
