In people with chronic myelogenous leukemia, the chromosomes in the blood cells swap sections with each other. A section of chromosome 9 switches places with a section of chromosome 22, creating an extra-short chromosome 22 and an extra-long chromosome 9.
Discovered on September 23, 1846, by John Couch Adams. Neptune was the first planet found by mathematical prediction rather than by observation. Unexpected changes in the orbit of Uranus led astronomers to deduce that its orbit was subject to gravitational perturbation by an unknown planet.
This date in science: Definitive discovery of Neptuneâs rings. A few days before the NASA spacecraft Voyager 2 skimmed by Neptune in 1989, it acquired images of a faint, continuous ring system encircling the planet. August 22, 1989. NASAâs Voyager 2 spacecraft swept past the planet Neptune on August 25, 1989.