On Tuesday, December 23, USGS Hawaiian Volcano Observatory scientists completed a helicopter overflight of Mauna Loa's summit and upper rift zones. This photo—captured looking north-northeast—shows South Pit (foreground) and Moku‘āweoweo caldera (middle distance) with Mauna Kea looming behind. USGS photo by M. Zoeller.

During the Mauna Loa summit overflight on Tuesday, December 23, a USGS Hawaiian Volcano Observatory geologist captured this northwest-looking view of southern Moku‘āweoweo caldera with Hualālai behind to the left and Haleakalā on Maui barely visible above distant clouds. Two prominent cones in this part of the caldera date from 1940 (center-right) and 1949 (center-left, on caldera wall). USGS photo by M. Zoeller.

At the end of their Mauna Loa summit overflight on December 23, USGS Hawaiian Volcano Observatory geologists passed the 2022 Northeast Rift Zone eruption site. In this photo, an older vent known as Steaming Cone is visible in the lower-left of the frame (red and white colors), with the 2022 fissure 3 cone just to the right of it (black and brown colors). 2022 lava channels leading down toward the Humu‘ula Saddle are also visible in the right side of the frame, along with Mauna Kea in the distance. USGS photo by M. Zoeller.

Kīlauea began its 39th lava fountaining episode the night of December 23, one year to the day from when this eruption began. This view was taken from the publicly accessible viewing area on Crater Rim Drive near Keanakākoi Overlook within Hawaiʻi Volcanoes National Park. While the fountains from the north and south vent were somewhat obscured by the rain and fog that evening, the glow illuminated the region around the fountains, highlighting the silhouettes of eruption viewers. USGS photo by M. Decker. 

Kīlauea began its 39th lava fountaining episode the night of December 23, one year to the day from when this eruption began. This view was taken from the publicly accessible viewing area on Crater Rim Drive near Keanakākoi Overlook within Hawaiʻi Volcanoes National Park. While the fountains from the north and south vent were somewhat obscured by the rain and fog that evening, the glow illuminated the region around the fountains, highlighting the silhouettes of eruption viewers. USGS video by M. Decker. 

Episode 39 of the ongoing Halemaʻumaʻu eruption at the summit of Kīlauea volcano began on December 23, 2025, at approximately 8:20 p.m. and ended abruptly at 2:13 a.m. HST on December 24, 2025, after about 6 hours of continuous fountaining. USGS photograph by Lis Gallant.