that would take over two hours, and the descent stage was jettisoned. The approach and rendezvous were conducted as near as possible to what was planned for the lunar missions. To demonstrate that rendezvous could be performed by either craft, Spider was the active party during the maneuver. McDivitt brought Spider close to Gumdrop, then maneuvered the LM to show each side to Scott, allowing him to inspect for any damage. Then, McDivitt docked the craft. Due to glare from the Sun, he had trouble doing this and Scott guided him in. During the later missions, the job of docking the two spacecraft in lunar orbit would fall to the command module pilot. After McDivitt and Schweickart returned to Gumdrop, Spider was jettisoned, its engine fired to fuel depletion remotely by Mission Control as part of further testing of the engine, simulating an ascent stage's climb from the lunar surface. This raised Spider to an orbit with apogee of over . The only major lunar module system not fully tested was the landing radar, as this could not be done in Earth orbit. Sixth through eleventh days (March 8–13) Apollo 9 was to remain in space for about ten days to check how the CSM would perform over the period of time required for a lunar mission. Most major events had been scheduled for the first days so that they would be accomplished if the flight needed to be ended early. The remaining days in orbit were to be conducted at a more leisurely pace. With the main goals of the mission accomplished, the hatch window was used for special photography of Earth, using four identical Hasselblad cameras, coupled together and using film sensitive to different parts of the electromagnetic spectrum. Such photography allowed different features of the Earth's surface to appear, for example, tracking of water pollution as it exits mouths of rivers into the sea, and the highlighting of agricultural areas using infrared. The camera system was a prototype, and would pave the way for the Earth Resources Technology Satellite, predecessor to the Landsat series. The photography was successful, as the ample time in orbit meant the crew could wait to allow cloud cover to pass, and would inform Skylab's mission planning. Scott used a sextant to track landmarks on the Earth, and turned the instrument to the skies to observe the planet Jupiter, practicing navigation techniques that