Hubble telescope's flaws not fatal

The public's perception of the Hubble telescope is of a $1.5 billion piece of crippled hardware drifting through space. But despite the stargazer's optical flaw, it not only is working but is doing the ground-breaking research its builders intended.

The flawed primary mirror hasn't affected 60 percent of the spacecraft's instruments. The two instruments that are affected, however -- the wide field and planetary cameras -- are the ones that produce the images that Americans have come to expect from their space program. So the perception persists that the telescope is broken.

In reality, it is reproducing images 10 times better than any telescope on Earth.

For the first time, astronomers have seen the planet Pluto as a body distinct from its natural satellite Charon. Before the Hubble was launched, this pair looked like a small ball with a bump on its surface. Resolution this good means we can study the chemical composition of both bodies without the necessity of sending a probe.

A telescope as expensive as the Hubble, by definition, ought to return great photographs of the planets, but what about the stuff way out there -- the job the space telescope was built for?

In the Orion nebula, the telescope has discovered a young star spewing a single light-years-long jet. In the Virgo galaxy cluster, the telescope has revealed that the massive jet of plasma streaming from the M87 galaxy twists like a corkscrew.

The most important photographs the Hubble has taken may be of distant quasars, those extremely luminous, compact objects that appear to be billions of light-years away from Earth. For years it has been theorized that if another massive object like a galaxy were to be positioned directly between us and the quasar, we would see the more distant quasar as a ring or group of individual points as a result of gravity bending its light.

One of the Hubble's first discoveries was the "Einstein Cross." The photograph's four images of the same quasar equally spaced around a distant galaxy have confirmed the theories Albert Einstein developed 80 years ago.

Three of the five instruments aboard the spacecraft don't take photographs -- instead, they measure the properties of light -- and aren't affected by the mirror flaws. Two of these instruments, the Goddard and wide-field spectrographs, have made remarkable observations.

Recently, however, the National Aeronautics and Space Administration's agony continued when a power supply problem forced the indefinite shutdown of the Goddard instrument. This will surely not be the Hubble's last problem, and that knowledge underscores the vulnerability of the entire American space effort.

Every time we launch a vehicle into space, whether it carries humans or hardware, we are dealing with the unknown. Few if any systems we send up can be described as operational. The experience of space is one of experiment rather than certainty.

The exploration and utilization of space provides us with incalculable benefits, but it also pushes technologies to their limits.