Workshop: Paint Black Holes with Light

Meet researchers from the Center for Gravity at the Niels Bohr Institute and explore the fascinating world of gravity as we create striking images of black holes painted with light.

A black hole is a region in space where gravity is so strong that nothing can escape – not even light. Yet scientists can still study them by observing their surroundings: watching stars orbit them, detecting ripples in spacetime when black holes collide, and even capturing images of light bending around them. In this workshop, you’ll discover how researchers observe black holes and learn more about these mysterious cosmic phenomena.

With guidance from experts from the Center for Gravity at the Niels Bohr Institute, you’ll design your own black hole on paper before bringing it to life by painting it with light. By keeping a camera’s “eye” open for a long time, it can collect more light – the same technique used to capture spectacular images of distant nebulae and galaxies. Using this method, along with a variety of light sources including flashlights and fairy lights, you’ll create your very own black hole. Afterwards, your finished image will be sent to your phone, or to the phone of the adult accompanying you, so you can keep it as a souvenir.

The workshop is part of Black Hole Week, organised by the Center for Gravity, a Center of Excellence at the Niels Bohr Institute dedicated to research into gravity, black holes and the most extreme phenomena in the universe.

The workshop takes place at Rundetaarn, is included in the standard admission ticket, and requires no advance booking. The workshop facilitators speak both Danish and English.

guests will also have the opportunity to explore the exhibitions Refractions of Ice and Ole Rømer and the Great Discovery, Rundetaarn’s introductory exhibition. Visitors are also welcome to walk up the beautiful Spiral Ramp to the top of the Tower and enjoy the panoramic views over Copenhagen.

The workshop is part of Rundetaarn’s LIGHT YEAR 2026 programme, marking the 350th anniversary of Ole Rømer’s discovery of the speed of light.