For Valentine’s Day, the Copernicus Sentinel-2 mission picks out a heart in the landscape north of Mount St Helens in the US state of Washington.

Zoom in to explore this image at its full 10 m resolution.

Mount St Helens is an active volcano, known for its eruption on 18 May 1980, one of the most destructive volcanic explosions ever recorded in North America. The event killed 57 people and thousands of animals, felling trees over an area of some 500 sq km.

The eruption was caused by an earthquake that led to a massive landslide of the volcano’s north face. The volcano then exploded, depositing widespread ash and melting the mountain’s snow, ice and glaciers that formed a number of volcanic mudslides – or lahars. Some of these lahars are visible in light brown, particularly northwest of the crater.

This false-colour image from January 2025 has been processed using a combination of spectral bands to highlight vegetation in red, while areas with little or no vegetation appear brown, with water bodies dark or black.

The heart-shaped feature surrounded by snow at the centre of the image is Spirit Lake, a popular tourist destination for many years until the eruption.

Before the catastrophic event, Spirit Lake was a typical alpine lake, surrounded by dense forests. The landslide and the eruption displaced the lake, raising its surface level by about 60 m and reshaping its basin. Thousands of trees were blasted into the lake, forming a dense floating log mat, which is still visible in the image as a lighter, brown area.

The lake’s drainage system was compromised, so a new tunnel had to be built to prevent uncontrolled flooding. Once the new water level stabilised, it created the current heart-like outline.

In the lower-central part of the image, the rectangular areas show land division, possibly for timber processing, with the brown areas showing where trees have been cleared. We can see how the white snow cover ends in these areas, as the elevation drops.

Satellite missions such as Copernicus Sentinel-2 not only deliver amazing views of Earth, but are also vital for monitoring remote and unique environments. From their vantage point in space, satellites systematically image and measure changes taking place, both natural changes and those linked to human activity, so that information is available to protect our planet and its inhabitants.