https://www.nao.ac.jp/en/news/topics/2009/20090327-iya2009.html
IYA2009 Global Project: 100 Hours of Astronomy, 2-5 April 2009 | NAOJ - National Astronomical...
The 100 Hours of Astronomy Cornerstone Project is a worldwide event consisting of a wide range of public outreach activities, live science ...
100 hours of astronomy
https://www.eso.org/public/events/special-evt/100ha/
100 Hours of Astronomy | ESO
ESO, European Organisation for Astronomical Research in the Southern Hemisphere
100 hours of astronomyeso
https://www.planetary.org/space-images/100-hours-of-astronomy-nigeria
100 Hours of Astronomy in Nigeria | The Planetary Society
100 Hours of Astronomy Event organized by Astronomers Without Borders, Nigeria.
100 hours of astronomyin nigeriaplanetarysociety