– The Contreras Fire burning in southern Arizona is now 20,360 acres, the Arizona Republic reports. According to the AP, the lightning-caused fire, which started June 11 on the Tohono O’odham Indian Reservation, is 40% contained. More than 300 firefighters are working to contain the fire, which is expected to be fully contained by Sunday. The Kitt Peak National Observatory was evacuated due to the fire, but no telescopes or other science facilities appear to have been damaged, CNN reports. Four structures, including a dormitory and a residence, were lost to the fire on Friday. While an evacuation order hasn’t been issued, residents of the Hay Hook Ranch Estates area “should consider voluntarily relocating outside the affected area with family/friends,” the Arizona Republic reports. The Contreras Fire is burning on the Tohono O’odham Indian Reservation, about 8 miles southeast of Kitt Peak.