Sciences division

The sciences division was the corps of officers within Starfleet who specialized in scientific or medical research and control functions aboard starships, on starbases and at Starfleet Command. Members of the sciences division may of specialized in any number of areas including: sensors, research, theoretical and laboratory work, biological studies or trained as technicians, medics and surgeons.

In the mid-23rd century, navigation also fell under the jurisdiction of the sciences division aboard Federation starships. 

Division colors and uniform
Beginning in the United Earth Starfleet in the mid-22nd century, line officers and non-commissioned officers assigned to the sciences division wore blue division stripes on their uniforms. (Star Trek: Enterprise) By the 2230s, the division was represented by a mustard green color, before switching back to the familiar blue by the 2240s and remaining in place until the early 2270s. During this time, science division officers had a speciality insignia which was included in their assignment patch. (Star Trek: The Original Series)

In the early 2270s, the introduction of a new Starfleet uniform saw the sciences division showing two different division colors. Science research and technical staff wore orange behind their Starfleet badge, on uniform bands, accessories and epaulets. The medical crew now wore green badge backings and accessories. 

The division colors were changed once again in the late 2270s, with green continuing to represent the medical personnel, but gray was the new division color for research and technical staff. ( et al.)

By the 2350s the two departments were combined together again and were once again represented by a blue color. (Star Trek: The Next Generation) In the mid-2360s a second type of uniform displayed a slightly different color, jungle green, as the division color. (Star Trek: Deep Space Nine; Star Trek: Voyager)

With the adoption of a new uniform in 2373, the jungle green from the previous type B uniform was adopted as the main sciences division color. ( et al.) This color remained in use until 2386, when yet another new uniform reverted the color to the traditional blue. 

By the 29th century, the sciences division was represented by an olive gray division color.