the crater has enlarged over a three-week period

Detailed Description
Aerial images of the Halema‘uma‘u crater from May 27, 2018 (upper image) and June 18, 2018 (lower image). Note how the crater has enlarged over a three-week period, as shown in the June 18 photo. Also visible, are cracks on the crater floor due to ongoing subsidence at the summit
Sources/Usage
Public Domain.