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Photo: Jakob Arthur Andersen / clearskyastro.dk
KOSMOS – Astro Festival in the Round Tower
Between February 7 and March 21, Rundetaarn invites you to an astro festival in Christian IV’s stargazing tower on Købmagergade. Framed by an exhibition featuring spectacular photos by one of Denmark’s best astrophotographers, the program also includes scientific talks in Danish, concerts, special events, and other stellar moments for both children and adults.
Exhibition with Astrophotographer Jakob Arthur Andersen
February 7th – March 21st
Embark on a journey thousands of light-years into space as Jakob Arthur Andersen showcases his stunning images of the night sky and deep space in the Library Hall. With telescope and camera, he has spent countless hours capturing the wonders of our universe, the solar system, and the landscapes of the night. Experience his very best photographs—from the Milky Way to distant galaxies—at the Round Tower.
Visit the Observatory
Tuesdays and Wednesdays, 6–9PM
Join our astronomers for a night of star and planet gazing. During the winter months the Observatory is open and manned every Tuesday and Wednesday evening from 18 to 21. No reservation is needed – the visit is included in your entrance ticket.
Please Note: Stargazing is not possible if the sky is overcast. The Round Tower cannot guarantee visible stars or planets if the weather does not permit.
If it is cloudy or overcast, our astronomers will still keep the Observatory open for visits and will in stead tell you more about the telescope and the old Observatory.
Concert: Bremer/McCoy
March 3rd, 8PM
Listen to the sound of Cosmos when the meditative, dub-inspired jazz duo Bremer/McCoy offers their interpretation as they visit the Round Tower to perform tracks from their latest album, titled Kosmos after the wondrous universe.
Planet Workshop for Kids
February 16th, 10AM – 2PM
Color planets and create your own solar system at Rundetaarn’s creative drop-in workshop for children and their adults.
Planet Workshop for Kids
Color the planets and create your own Solar System when the Round Tower invites you to join a creative drop-in workshops for children and their adults.
Create unique and imaginative celestial bodies! Armed with scissors, glue, cotton balls and crayons, only imagination sets the limits.
The Round Tower provides tools and drawing kits, but you decide the patterns and colors of your celestial creations.
The workshop is open to all who have paid regular admission, though spaces are limited.
The event is part of the program for Round Tower’s astro festival “KOSMOS”.
Planet Workshop for Kids
Let your creativity run free and create your own planets or Solar system when the Round Tower invites you to a creative drop-in workshop for children.
Create unique and imaginative celestial bodies! Armed with scissors, glue, cotton balls and crayons, only imagination sets the limits.
The Round Tower provides tools and drawing kits, but you decide the patterns and colors of your celestial creations.
The workshop is open to all who have paid regular admission, though spaces are limited.
The event is part of the program for Round Tower’s astro festival “KOSMOS”.
Photo: Jakob Arthur Andersen / clearskyastro.dk
Exhibition with Astrophotographer Jakob Arthur Andersen
Embark on a journey thousands of light-years into space as one of Denmark’s best astrophotographers presents his spectacular images in the Library Hall. Experience Jakob Arthur Andersen’s fascinating shots of the night sky and deep space – the Universe like you’ve never seen it before.
With a telescope and camera, Jakob Arthur Andersen has spent countless hours capturing our fantastic Universe, Solar System, and the landscapes of the night. The exhibition in the Library Hall showcases his finest images – from the Milky Way to distant galaxies.
Jakob Arthur Andersen’s works are a central part of the Round Tower’s astro festival “COSMOS”, which also features scientific talks, astronomy for children, and other stellar experiences – all with the cosmos in focus.
Science Meets Art
Astrophotography demands patience and precision. The process relies not only on technical skill but also on the clarity of the sky and the whims of the weather. Denmark’s climate often poses a challenge, which means that photos are frequently created over multiple nights. When the weather is favorable, you must act quickly—sometimes conditions are optimal for only a few hours at a time. On other nights, the sky can be cloudless and starry all night long.
Jakob’s images require long exposure times and are composed of many individual shots that enhance each other. He views digital editing as his palette and the camera as his brush—astrophotography, to him, is a unique fusion of science and art.
About Jakob Arthur Andersen
Astrophotographer and lecturer Jakob Arthur Andersen opens a window to infinity with his telescope and camera—a visual time machine reaching deep into the vast cosmos.
Jakob is a self-taught astrophotographer and internationally recognized; he has won several awards, including first place in the prestigious International Photography Awards for two consecutive years.
When he’s not observing the universe from his backyard on the island of Falster, he wanders through the quiet nighttime landscapes with his camera and tripod, always in search of new subjects under the night sky that stretches majestically over the dark Danish plains.
This event is part of the program for the Round Tower’s astro festival “COSMOS”.
Astro Evenings for Families
Join us during selected days in the autumn break for Astro Evenings for children and their adults, with special evening openings for families at the Observatory and a creative planet workshop.
Visit the Observatory
Remember to wear warm clothes when we open the Observatory especially for families and focus the telescope lens on Saturn or the Moon, weather permitting. There is limited space in the Observatory at any one time, so don’t forget to visit the planet workshop in the Reading Room, where you can create your own celestial bodies. You can also buy a cup of hot cocoa or other refreshments for children in the Library Hall.
Planet Workshop
Color the planets and create your own solar system when the Round Tower invites children and adults to a creative drop-in workshop. Try your hand at scissors, glue, cotton balls, and beautiful wax crayons that can be blended with water.
The Round Tower provides colors, tools, and drawing kits, but you decide the patterns and colors of the celestial bodies!
Note: The Round Tower cannot guarantee that we will be able to see celestial objects through the telescope if the weather does not allow it! However, if the weather doesn’t cooperate, we will still keep the Observatory open, and our astronomers will instead share more about the Observatory and the large refractor telescope, which can magnify 80-450 times.
Tickets include regular entry but must be booked in advance.
Astro Evenings for Families
Join us during selected days in the autumn break for Astro Evenings for children and their adults, with special evening openings for families at the Observatory and a creative planet workshop.
Visit the Observatory
Remember to wear warm clothes when we open the Observatory especially for families and focus the telescope lens on Saturn or the Moon, weather permitting. There is limited space in the Observatory at any one time, so don’t forget to visit the planet workshop in the Reading Room, where you can create your own celestial bodies. You can also buy a cup of hot cocoa or other refreshments for children in the Library Hall.
Planet Workshop
Color the planets and create your own solar system when the Round Tower invites children and adults to a creative drop-in workshop. Try your hand at scissors, glue, cotton balls, and beautiful wax crayons that can be blended with water.
The Round Tower provides colors, tools, and drawing kits, but you decide the patterns and colors of the celestial bodies!
Note: The Round Tower cannot guarantee that we will be able to see celestial objects through the telescope if the weather does not allow it! However, if the weather doesn’t cooperate, we will still keep the Observatory open, and our astronomers will instead share more about the Observatory and the large refractor telescope, which can magnify 80-450 times.
Tickets include regular entry but must be booked in advance.
Autumn Holiday: Science and Other Stellar Experiences
Autumn Break is filled with curiosity at Christian IV’s Historic Observatory Tower. Dive into creative planet workshops for kids, experience the magic of the Observatory at the top of the tower, and explore the science exhibition “From Science to Society.”
Planet Workshops for Kids
October 14th–18th, 10-16
Color the planets and create your own Solar System when the Round Tower invites you to join creative drop-in workshops for children and adults. Try your hand at scissors, glue, cotton balls, and beautiful wax crayons that can be blended with water to create colorful planets.
The Round Tower provides tools and drawing kits but you get to decide the look and design of the celestial bodies.
The workshop is open to everyone with a regular entrance ticket, but there are limited spots available.
Astro Evenings for Families
October 14th & 17th, 18-21
Join us when we open the Observatory exclusively for children and their adults and adjust the telescope to see Saturn or the Moon if the weather permits. During the evening you can also make planets in our open planet workshop in the Reading Room next to the Library Hall or solve fun astronaut challenges in the Spiral Ramp.
Remember to dress warmly for the Observatory!
Registration is required for Astro Evenings.
Exhibition: From Science to Society
Every day until October 20th
Learn more about both famous and unknown scientists together in the Round Tower’s Library Hall, where you can currently explore the exhibition “From Science to Society,” presented in collaboration with the Society for the Dissemination of Natural Science (SNU).
From Monday to Thursday in week during Autumn Break, there will be “Mirror Image Days” in the exhibition, where you can delve into the chemistry behind life’s twists and turns! The building blocks of nature exist as mirror images – something called ‘chirality’. You may have never heard of it before, but once you become aware of chirality, you’ll see it everywhere: your hands, your shoes, you name it – even the Round Tower is chiral!
At the experiment tables in the exhibition, you will be able to smell and taste mirror image molecules and learn more about chirality. Build the organic molecules you taste and discover why they are called ‘mirror image forms’.
Planet Workshop for Kids
Color the planets and create your own Solar System when the Round Tower invites you to join creative drop-in workshops for children and adults.
Try your hand at scissors, glue, cotton balls, and beautiful wax crayons that can be blended with water to create colorful planets.
The Round Tower provides tools and drawing kits but you get to decide the look and design of the celestial bodies.
The workshop is open to everyone with a regular entrance ticket, but there are limited spots
Look Through the Telescope
Join our astronomers for a night of star and planet gazing. During the winter months the Observatory is open and manned every Tuesday and Wednesday evening from 18 to 21. No reservation is needed – the visit is included in your entrance ticket.
Used by the University of Copenhagen until 1861, the Round Tower is Europe’s oldest functioning observatory. Today, it is open to peek inside year-round and manned on special days by the Round Tower’s astronomers who invite our guests inside to take a look through the refracting telescope with 80-450 x magnification.
Please Note: Star and planet gazing is not possible if the sky is overcast.
The Round Tower cannot guarantee visible heavenly bodies if the weather does not permit.
If it is cloudy or overcast, our astronomers will still keep the Observatory open for visits and will in stead tell you more about the telescope, the night sky and the old Observatory.
What is visible on the night sky?
As mentioned above, the Round Tower cannot guarantee clear skies and perfect visibility if the weather does not allow, but here you can see the prognosis for which stars or planets our astronomers will be looking for the next couple of months:
JANUARY
Tuesday 7/1: Venus, Saturn, Moon, Jupiter, Mars
Wednesday 8/1: Venus, Saturn, Moon, Jupiter, Mars
Tuesday 14/1: Venus, Saturn, Moon, Jupiter, Mars
Wednesday 15/1: Venus, Saturn, Moon, Jupiter, Mars
Tuesday 21/1: Venus, Saturn, Jupiter, Mars
Wednesday 22/1: Venus, Saturn, Jupiter, Mars
Tuesday 28/1: Venus, Saturn, Jupiter, Mars
Wednesday 29/1: Venus, Saturn, Jupiter, Mars
FEBRUARY
Tuesday 4/2: Venus, Saturn, Moon, Jupiter, Mars
Wednesday 5/2: Venus, Saturn, Moon, Jupiter, Mars
Tuesday 11/2: Venus, Saturn, Moon, Jupiter, Mars
Wednesday 12/2: Venus, Saturn, Moon, Jupiter, Mars
Tuesday 18/2: Venus, Jupiter, Mars
Wednesday 19/2: Venus, Jupiter, Mars
Tuesday 25/2: Venus, Jupiter, Mars
Wednesday 26/2: Venus, Jupiter, Mars
MARCH
Tuesday 4/3: Venus, Jupiter, Mars, Moon
Wednesday 5/3: Venus, Jupiter, Mars, Moon
Tuesday 11/3: Venus, Jupiter, Mars, Moon
Wednesday 12/3: Venus, Jupiter, Mars, Moon
Tuesday 18/3: Jupiter, Mars
Wednesday 19/3: Jupiter, Mars
Tuesday 25/3: Jupiter, Mars
Wednesday 26/3: Jupiter, Mars
Sun Observation Sundays
Every day during opening hours, visitors can peek at the telescope inside the Observatory dome on the tower top. On special days during the Summer Holiday, however, the Observatory will be open and manned for Sun observations.
Join us each Sunday from June 30th to August 11th as our astronomers operate the old telescope between 1-4PM. Look up into the skies yourself and take a closer look at the Sun and Sun Spots through a special lens while our astronomers guide you and answer questions about the heavenly bodies.
A visit to the Observatory is included in your entry fee.
Please note: The Round Tower cannot control the weather. If the sky is overcast, our astronomers cannot guarantee visibility of the Sun.
English subtitles available.