After fading into obscurity at about magnitude 12 to 13 during the early 20th century, GK Persei began displaying infrequent outbursts of 2 to 3 magnitudes (about 7 to 15 times quiescent brightness).
Setelah memudar dalam kegelapan di magnitudo 12 hingga 13 selama awal abad ke 20, GK Persei mulai menampakan ledakan-ledakan di magnitudo 2 hingga 3 (sekitar 7 hingga 15 kali kecerahan diam).