100 Hours of Astronomy 2023


100 Hours of Astronomy 2023

An IAU Outreach Global Project


Join the IAU Office for Astronomy outreach for a 100-hour, round-the-clock, round-the-globe celebration of astronomy aimed at engaging as many people as possible - from children to senior - with the sky and sharing the wonders of our astronomical surroundings.


From 1 to 4 October 2023, the IAU Office for Astronomy Outreach (OAO) will continue the legacy of celebrating 100 Hours of Astronomy. This year’s theme is One Planet.  We aim to create an experience that fosters a sense of unity, connection, and togetherness among the public, inspired by the camaraderie astronauts feel when returning from space missions, called the Overview Effect. This series of events will celebrate the beauty of our shared planet and promote global cooperation, environmental stewardship, and a collective commitment to a better future. 


The Overview Effect

The Overview Effect1 is a term coined to describe a profound and transformative shift in consciousness that astronauts often experience when viewing the Earth from space. It is a cognitive and emotional response to the breathtaking sight of our planet from orbit or the Moon. Key aspects of the Overview Effect include:

  • Awe and Unity: Astronauts describe an overwhelming sense of awe and unity as they gaze upon Earth from space. They see the planet as a fragile and interconnected ecosystem devoid of boundaries and divisions.
  • Increased Environmental Awareness: The experience fosters a deep appreciation for Earth's beauty and a heightened awareness of environmental challenges. Many astronauts return to Earth with a strong commitment to protecting the environment.
  • Shift in Perspective: The Overview Effect often leads to a shift in perspective, where individuals recognise the insignificance of individual conflicts and the importance of cooperation to address global issues.
  • Spiritual and Philosophical Insights: Some astronauts describe the experience as spiritual or philosophical, leading to a reevaluation of their life's purpose and a sense of interconnectedness with all living beings.
  • Motivation for Space Exploration: The Overview Effect has also served as motivation for further space exploration, as astronauts return with a sense of responsibility to explore space while ensuring the preservation of Earth.

The Overview Effect underscores the profound impact that space travel can have on the human perspective and underscores the importance of safeguarding our planet and working collaboratively to address global challenges.


100 Hours Astronomy  IAU Calendar of Outreach Global Events Submission

Once again, we will host a global map of events in which you can share your work with the world and be a part of the OAO's 100 Hours of Astronomy! If your event is open to the public, be sure to leave enough information for people to get involved – both in person and online! The first 50 events that enter their information will receive goodies from the OAO, including printed copies of the most recent CAPjournal issues. Be safe2, be inclusive, and share your event with the world! Add your event to the map using this form.



100 Hours Art Projects Competition

We are excited to offer participants the opportunity to engage in a collaborative art project that symbolises unity and interconnectedness. This project will allow us to create a collective artwork that embodies the festival's theme of astronomy and the overview effect. We ask you to create a piece of art: a painting, picture, poem, video, or any other creative medium. For your piece of art to be included, it must be submitted through this form, along with a picture or link to a video before 10 October 2023, 23:59 UTC. We invite artists of all ages to join in the competition. By sending us your piece of art, you agree for it to be shared on the IAU OAO social media pages, with your name linked to it. We will randomly select two entries to win a telescope courtesy of Sterren Schitteren Voor Iedereen (Stars Shine For Everyone - SSVI), University Ghent - Dept. Physics and Astronomy, Leiden University, and BRESSER.


Activity ideas

Do you need some ideas for your astronomy outreach event? Look through the community-driven ideas in our Office for Astronomy Outreach Toolkit. If you have developed or know of any exciting astronomy outreach activity format, please share it with the community. Additionally, you can look through last year's events at the 100 Hours of Astronomy 2022 page.


Let us share your work!

When spreading the word about your event on social media, be sure to use #100HoursOfAstronomy and #IAUoutreach so we can help promote your activity, too! Stay tuned to OAO’s social media channels (Facebook and Twitter) as we release more information and resources in the upcoming weeks.



[1] Yaden, D. B., Iwry, J., Slack, K. J., Eichstaedt, J. C., Zhao, Y., Vaillant, G. E., & Newberg, A. B. (2016). The overview effect: Awe and self-transcendent experience in space flight. Psychology of Consciousness: Theory, Research, and Practice, 3(1), 1.
[2] Please follow the health measures recommended by your country or local area when joining the 100 Hours of Astronomy activities.



Andrea Girolamodibari
100 Hours of Astronomy 2023 Project Manager
Email: public@oao.iau.org

Kelly Blumenthal
OAO Acting Director
Email: blumenthal.kelly@oao.iau.org
Tel: +81 80 8841 3569


More information

The IAU is the international astronomical organisation that brings together more than 12 000 active professional astronomers from more than 100 countries worldwide. Its mission is to promote and safeguard astronomy in all its aspects, including research, communication, education and development, through international cooperation. The IAU also serves as the internationally recognised authority for assigning designations to celestial bodies and the surface features on them. Founded in 1919, the IAU is the world's largest professional body for astronomers.


The IAU Office for Astronomy Outreach (OAO) is a joint project of the International Astronomical Union (IAU) and the National Astronomical Observatory of Japan (NAOJ). The mission of the OAO is to engage the public in astronomy through access to astronomical information and communication of the science of astronomy. This is implemented through a network of IAU National Outreach Coordinators (NOCs) and the IAU’s public engagement initiatives. The work of the OAO is about building bridges between the IAU and the global astronomy community of amateur astronomers, outreach professionals, educators, communicators, and the general public, and through international collaboration, to make the science of astronomy accessible to all.



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