The Hubble Space Telescope is a big tube in orbit around the Earth. It apparently has unfathomably acute visual resolution, as it can show details as small as a few inches wide from a distance of tens of millions of miles.
Live-action movie continuity
In 2003, an unknown agency used the Hubble Space Telescope to produce routine images of the surface of Mars. One batch of images, however, showed a smoldering impact crater, and upon further resolution showed a slightly blurry robotic figure standing on the planet's surface. The information was promptly passed on to Sector 7, who prepared to "welcome" the newly-arrived visitor.