John Burke was a Human scientist, the Chief Astronomer at the Royal Academy, United Kingdom, in the middle or late 21st century.
"Almost two hundred" years prior to a Federation-Klingon incident on Sherman's Planet, Burke mapped the area of space that included this planet.
During a 2268 mission briefing for this incident, Ensign Chekov mistakenly remembered Burke as being a Russian named "Ivan Burkoff". (TOS: "The Trouble with Tribbles")