What is Kawah Ijen?

About Kawah Ijen

• Kawah Ijen is a volcanic crater lake located in East Java, Indonesia.
• It is part of the larger Ijen volcano complex, which includes several other craters.
• The main attraction of Kawah Ijen is its stunning turquoise-colored crater lake.
• The vibrant color of the water is due to the high concentration of dissolved sulfuric acid and other minerals.
• The lake is the largest, highly acidic crater lake in the world.
• The lake has been included in UNESCO’s World Biosphere Reserves.
• The Ijen volcano complex is still active, and Kawah Ijen is one of the areas where volcanic activity is observed.
• The volcano releases sulfur gases, which can be ignited and produce impressive blue flames, especially at night. These flames are often referred to as "blue fire."
• The area around Kawah Ijen is known for traditional sulfur mining.

Key Facts Copernicus Sentinel-2 Mission

• It is a European wide-swath, high-resolution, multi-spectral imaging mission. 
• It comprises a constellation of two polar-orbiting satellites placed in the same sun-synchronous orbit, phased at 180° to each other.
• It aims at monitoring variability in land surface conditions, and its wide swath width (290 km) and high revisit time (10 days at the equator with one satellite and 5 days with 2 satellites under cloud-free conditions which results in 2-3 days at mid-latitudes) will support monitoring of Earth's surface changes.

Q1) What is a crater?

A crater is a bowl-shaped depression or hollow in the ground or on the surface of a celestial body, such as the Moon, a planet, or even an asteroid. Craters are typically formed by the impact of objects from space, such as meteoroids, asteroids, or comets, striking the surface. 

Source: Acid cauldron on Earth: World's largest acidic lake looks spooky from space