Editing Gemini 10 (section)

===First rendezvous===
Collins was unable to use the sextant for navigation as it did not seem to work as expected. At first he mistook airglow as the real horizon when trying to make some fixes on stars. When the image didn't seem right he tried another instrument, but this was not practical to use as it had a very small field of view.

They had a backup in the form of the computers on the ground. They made their first burn to put them into a {{convert|265|by|272|km|nmi|adj=on|sp=us|order=flip}} orbit. However Young didn't realize that during the next burn, he had the spacecraft turned slightly, which meant that they introduced an out-of-plane error. This meant two extra burns were necessary, and by the time they had docked with the Agena, 60% of their fuel had been consumed. It was decided to keep the Gemini docked to the Agena as long as possible, as this would mean that they could use the fuel on board the Agena for attitude control.

The first burn of the Agena engine lasted 80 seconds and put them in a {{convert|294|by|763|km|nmi|adj=on|sp=us|order=flip}} orbit. This was the highest a person had ever been, although the record was soon surpassed by [[Gemini 11]], which went to over {{convert|1000|km|nmi|sp=us|order=flip}}. This burn was quite a ride for the crew. Because the Gemini and Agena docked nose-to-nose, the forces experienced were "eyeballs out" as opposed to "eyeballs in" for a launch from Earth. The crew took a couple of pictures when they reached [[apogee]] but were more interested in what was going on in the spacecraft &mdash; checking the systems and watching the radiation dosage meter.

After this they had their sleep period which lasted for eight hours and then they were ready for another busy day. The crew's first order of business was to make a second burn with the Agena engine to put them into the same orbit as the Gemini 8 Agena. This was at 20:58 UTC on July 19 and lasted 78 seconds and took {{convert|105|m/s|ft/s|sp=us|order=flip}} off their speed, putting them into a {{convert|294|by|382|km|nmi|adj=on|sp=us|order=flip}} orbit. They made one more burn of the Agena to circularize their orbit to {{convert|377.6|km|nmi|sp=us|order=flip}}.