100 Hours of Astronomy

An IAU Outreach Global Project



100 Hours of Astronomy is a 100-hour, round-the-clock, round-the-globe celebration composed of a broad range of activities aimed at involving the public. The event welcomes amateur and professional astronomers, astronomy outreach professionals to host events sharing their knowledge and enthusiasm for the Universe with the general public. The goal is to enable as many people as possible, from children to senior citizens, to engage with the sky and gain a basic understanding of our astronomical surroundings.



2021 Edition

From 1-4 October 2021, the IAU Office for Astronomy Outreach will continue the legacy of celebrating 100 Hours of Astronomy. This year’s event will be themed “Together under one sky” drawing inspiration from how our community has come together during a time where physical contact wasn't - and in many places still isn't - possible. We encourage our global community to host or participate in events over these 100 hours, either online or in-person, with the consultation of local safety restrictions and WHO health guidelines.


We welcome astronomy projects of all kinds, including professional-amateur astronomers meet-ups, activities instigating critical thinking in young children and senior citizens, citizenship and global collaboration, and dark and quiet skies awareness through virtual tours, talks, sky observation activities, lectures, art projects and more!


There are numerous creative possibilities for activities and projects for the 100 Hours of Astronomy! Share your event in our IAU Global Outreach Event Calendar and the 10 activities that best connect communities around the world will win a telescope (see description below), in a special edition of the Telescopes for All programme. The first 100 events registered for 100 Hours of Astronomy will receive IAU Office for Astronomy Outreach goodies, including printed versions of Communicating Astronomy with the Public Journal.


Once you have registered your event, we welcome you to check our online resources to help organise your event. 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!

SSVI also calls on every association and school that received an SSVI telescope in forty countries worldwide to make the telescopes available to as many as possible throughout the 100 Hours of Astronomy!


Stay tuned to our networks and channels as we release more information in the upcoming weeks.


Covid-19 Safety Measures

Please follow the health measures recommended by your country or local area when participating in the 100 Hours of Astronomy. We encourage you to work collaboratively online if possible.



Telescopes for All: 100 Hours of Astronomy Special Edition

Our partners, Stars Shine for Everyone in collaboration with Leiden University will donate one telescope to 10 outreach groups among the 100 Hour of Astronomy activities registered in the IAU Outreach Event Calendar. The awarded groups and their registered activities will be selected based on their creativity in connecting or reaching out to their communities (e.g. amateur astronomer groups broadcasting a live observation, virtual meet-ups between astronomers and the general public, virtual meet-ups and live observations at senior citizen's homes, and others).


Description of the Telescopes
BRESSER Skylux 70/700 refractor telescopes (donated in second hand, excellent conditions). The telescope comes with SSVI assembly with two eyepieces (20mm and 12mm, magnification resp.35X and 56X), prism, viewfinder, solar filter and camera. The telescopes come with the signatures of three astronauts and three Nobel Prize Winners. Due to covid times digitally signed.





- All decisions of the organizers about any aspect of the contest, including eligibility or disqualification of applications, comments and images, and final awarding, are final and cannot be appealed.

- By submitting information for the contest, participants consent to the use, reproduction, publication, transmission and dissemination of their name and artwork, and information relating to the contest by the contest organizers and/or partners, without compensation, in any publications or promotional material.

- The Prizes will be shipped to the winners as the COVID-19 measures allow.

- SSVI and the IAU Office for Astronomy Outreach reserves the right to make changes to the contest at any time without prior notice, to temporarily interrupt the contest, or to cancel the contest without justifying or being in any way accountable for this decision. No damages or compensation may be claimed.



The SSVI project is a cooperation between Volkssterrenwacht A.Pien vzw (Public Observatory Armand Pien) and Ghent University. The project is based on the idea that ”All children in special education and vulnerable people should have the opportunity to admire the starry sky with the help of a telescope.” says project leader and founder Jean-Pierre Grootaerd, space teacher Euro Space Society.   



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