File:Vog from Wolf volcano, Galapagos Islands (MODIS 2015-06-06).jpg

English: The thirty-three year-long rest of Wolf Volcano, located on the northern part of Isla Isabella in the Galapagos, was broken by a spectacular eruption on May 25, 2015. Following an explosion, tall lava fountains and effusive lava flows poured from a moderately large fissure eruption. Initial estimates said that steam and ash plume may have risen up to 45,000 ft. (14 km) during the initial explosive eruption. Large lava flows were seen descending from the fissure and flowing to the southeast. They reached the sea two days later.

Isla Isabella is the largest island in the Galapagos, and was formed by about one million years ago by the action of six different shield volcanoes, including Wolf Volcano. Five out of the six original volcanoes are still considered volcanically active. Despite the volcanic activity, the island is home to many endemic species, including the rare pink or rosada iguana (Conolophus marthae). First discovered in 1986, the large lizard is found only on the northern end of Isabela Island, living on and around Wolf Volcano. The eruption created concern for the welfare of the breeding colonies of the iguana, as well as for other island endemics. The National Park staff ran an aerial survey that confirmed that the main habitats of the local endemic fauna, including the pink iguana, appeared to be intact after the eruption.

The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA�s Terra satellite flew over the cloudy region on May 31 and captured this true-color image. The Galapagos Islands lie under cloud cover, but black border lines have been overlain on the image to show their location. The red hotspot marks the location of the lava flow from Wolf Volcano. A fine grayish haze surrounds the volcano like a halo, and stretches to the west from the summit. This haze is known as �vog� � a combination of fog, smog and volcanic gases that often is formed from active volcanoes. More scientifically, vog can be defined as �a visible haze comprised of gas and an aerosol of tiny particles and acidic droplets, created when sulfur dioxide and other gases chemically interact with sunlight and atmospheric oxygen, moisture and dust�.