Carl Sagan Day

In celebration of Carl Sagan Day, observed on November 9, people honour the birth and legacy of Carl Sagan (born November 9 1934).

History of Carl Sagan Day

Carl Sagan was an American astronomer, planetary scientist and science communicator whose popular works—like the TV series Cosmos: A Personal Voyage and books such as Pale Blue Dot—brought the wonders of the universe into the homes of millions.
Carl Sagan Day began when science-outreach organisations chose his birthday, November 9, to honour his contributions and promote curiosity about science and the cosmos.

Why is Carl Sagan Day important?

This day is important because it reminds us of the value of science-communication: how one person’s dedication to explaining the universe can inspire generations to look up, ask questions, and explore.
It also encourages us to remember that science is not just for specialists—it can be accessible, exciting, and a part of everyday life.

• It honours the legacy of a scientist who bridged research and popular understanding.
• It encourages public curiosity about astronomy, planetology and the cosmos.
• It celebrates educational outreach and the idea that science is for all people.
• It highlights the sense of wonder and humility we feel when we realise our place in the universe.
• It offers a moment to think about how science shapes our lives and our future.

How to Celebrate Carl Sagan Day

Since Carl Sagan Day celebrates curiosity, discovery and science, it’s fitting to celebrate it—by engaging in activities that reflect the spirit of Sagan’s work. For example, one might host or attend a stargazing night, watch episodes of “Cosmos”, or read one of his books. Reflecting on our place in the universe and sharing that awe with others is also meaningful.
Here are some simple ideas to mark the day:

• Watch Cosmos or a documentary about space and planets.
• Attend or organise a stargazing event with friends or family.
• Read a chapter from Sagan’s book “Pale Blue Dot” or another of his works.
• Encourage young people’s interest in science with an experiment or telescope session.
• Share a quote or idea from Carl Sagan on social media or with someone who might appreciate it.

Carl Sagan Day Dates Table