First invented late in Era-0, the graviscope is an instrument that makes gravitational waves visible.  The first graviscopes were large and unwieldy, mainly used in ground-based observatories.  The graviscope revealed much about space, showing the locations of black holes, dark matter clusters, and many other objects that would not otherwise have been found.

Graviscopes are also useful for detecting ships traveling faster than light, as doing so distorts the fabric of space-time, creating gravitational waves.

Midway through Era-1, graviscope technology was developed to the point that it became a practical instrument for space voyages.  As a result, space travel became substantially safer.  Ships that would have previously been lost in gravitational-wave storms, or swallowed by black holes were able to avoid these fates.

Early graviscopes were based on laser interferometry, while later designs changed to a mechanism combining nanotechnology with the exotic material known as gravitonium.

There was a previous version of the graviscope used in the Empire of 1,000,000 Suns, but it was never developed there beyond the level of the ground-based observatory.  The legendary engineer Kroah Dashan wrote a famous treatise on the use of graviscope data in finding the optimal placement for stargates.