April 20th has been designated as the "World Night" in defence of the Night Sky and the Right to Observe the Stars as a cultural, scientific and environmental humankind heritage. Every year on April 20th we remind ourselves of the need to preserve our right to view a dark night sky full of stars and to take steps to prevent its disappearance. World Night on April 20th is an opportunity to get actively involved in many ways: Switch-off unnecessary lights at night to recover the stars and at the same time save energy and slow down climate change. Organize artistic...