It's not quite that bad. Hubble is primarily optical wavelengths. The other Great [space-based] Observatories are in IR, X-rays, and gamma rays: https://en.wi

It's not quite that bad. Hubble is primarily optical wavelengths. The other Great [space-based] Observatories are in IR, X-rays, and gamma rays: https://en.wikipedia.org/wiki/Great_Observatories_program https://en.wikipedia.org/wiki/Great_Observatories_program The notion of grouping them as "Great Observatories", AFAIK, came circa the mid-1980s, after Hubble was already getting underway in earnest.