Lagoon Nebula. Optical Credit: NASA, ESA, and STScI. Near-infrared Credit: NASA, ESA, and STScI. Click on the button below to access the full scenario: Teacher Scenario Short description This activity emphasizes the importance of the invisible part of the electromagnetic spectrum, as a means of investigating the cosmic structure and evolution. Age of the students 15-18 years old Duration 8-10 hours Educator Information Name and Surname: George Klimis Country and school: Greece