Janet Hanula Mattei (née Akyüz; January 2, 1943 – March 22, 2004) was a Turkish-American astronomer who was the director of the American Association of Variable Star Observers (AAVSO) from 1973 to 2004.

Later, she was offered a job by Dorrit Hoffleit at the Maria Mitchell Observatory in Nantucket, Massachusetts.

She worked at Leander McCormick Observatory in Charlottesville, Virginia from 1970 to 1972 and received her M.A.

[citation needed] As head of the AAVSO for over 30 years, she collected observations of variable stars by amateur astronomers from around the world.

Under her direction, the database of the association was made available to educators[3] and also assisted non-professional astronomers access the Hubble Space Telescope.