CAPE CANAVERAL, Fla. (Reuters) - The U.S. space shuttle Columbia landed in Florida on Friday, ending a 16-day mission marred by the botched release of a $10 million solar observatory. The spaceship glided to a touchdown on the runway at Kennedy Space Center in Florida at 7:20 a.m. EST (1220 GMT). Six astronauts returned to face an inquiry into how a routine satellite deployment went badly wrong and left a 1,360 kg solar observatory spinning in space. Crew error or a computer glitch was to blame. The free-flying satellite was not properly activated before being released and was knocked into a slow tumble when the astronauts first tried to retrieve it with the shuttle`s robot arm. Spartan was eventually hauled aboard Columbia manually during a dramatic rescue by two spacewalking astronauts. Its two-day mission to study the Sun`s fiery outer atmosphere was lost. The spacecraft could not be re-released. Although NASA officials admitted the Spartan failure was a disappointment, they hailed the success of scientific experiments and two spacewalks. The mission`s two spacewalks, by NASA`s Winston Scott and Takao Doi of Japan, were the last in-orbit dress rehearsals before construction starts on the international space station next summer. Columbia`s international crew included the first Indian-born woman to fly in space and the first Ukrainian to orbit on a U.S. spaceship. Doi became the first Japanese to walk in space.