Many astronomers contend that if a new space-based telescope were to be designed today it would be built very differently from the Hubble.

The system produces images that are nearly equivalent to those obtained from space-based telescopes.

The observatory can "see" in wavelengths of light that no Earth or space-based telescope can detect.

However, many of the methods can work more effectively with space-based telescopes that avoid atmospheric haze and turbulence.

Pulse tubes will be particularly useful in space-based telescopes where it is not possible to replenish the cryogens as they are depleted.

Scheduled to launch in 2009, the space-based telescope will search for Earth-sized planets passing in front of other stars.

Second, a space-based telescope could observe infrared and ultraviolet light, which are strongly absorbed by the atmosphere.

This acceleration was later measured more accurately by other ground-based and space-based telescopes, confirming Hubble's finding.

Deciding between building ground- versus space-based telescopes is complex.

These wavelengths are also difficult or impossible to study from the ground, justifying the expense of a space-based telescope.