July 20, 2025 — Monitoring Kīlauea summit eruption episode 29

During episode 29 of lava fountaining from the ongoing Kīlauea summit eruption, a USGS scientist uses a laser rangefinder from the caldera rim to measure the width and distance of lava channels—data that helps estimate the flow’s velocity. USGS staff visit this hazardous area with permission from Hawai‘i Volcanoes National Park. From this area of the crater rim, the team of scientists were able to record lava flowing at speeds of 16–20 feet per second (5–6 meters per second). USGS photo by N. Thomas.