Event Organiser RESOURCES (2025)

This webpage is for astronomy Event Organisers who want to integrate activities from the 100 Hours Under One Sky project into their 2-5 Oct 2025 stargazing events, or otherwise support the event or use it to draw attention to their activities.

Updates:

• Will be here!

Jump to:

• How to use 100 Hours during your event

• Media / graphics packs for download

• Hands-on activities for download
  

what is 100 Hours Under ONe SKy

100 Hours Under One Sky is a project offering beginner-level stargazing activities which can be carried out at home or integrated into outreach events with very little effort. The activity is self-led from a website, where users can complete four simple challenges to win virtual ‘badges’ and see their achievements appear on our UK map.

Challenges include finding the Plough and Saturn (but please don’t tell people this - let it be a surprise).

We are running this project in support of 100 Hours of Astronomy, a global, mass-participation event led by the International Astronomical Union’s Office of Astronomy Outreach (IAU OAO) with the goal of making astronomy accessible to everyone. Every year, people in over 60 countries all around the world participate by doing astronomy activities during the 100 Hours period.

We ran a Zoom event on 2 September to show people through the app, and event organisers will have a week to have a go with a special preview site from 2-9 September, so you can see how it works and know what to expect (You can also help us identify any glitches!). This opportunity and link will be advertised on the AstroMailbox astronomy communicators’ mailing list. If you are not on this mailing list you can email us to request an invitation..

The 100 Hours event runs 2-5 October 2025, but our website will remain active afterwards for some time. So if it’s cloudy during the 100-hours period, people can try again later. However, if they participate outside the 100-hours period, their achievement markers will appear in grey. But we don’t want people to think ‘oh I’ll just do it later’ so please don’t tell people about this feature unless it is cloudy during the 100 Hours.

How to use 100 hours at an event

If you are running an event, please register it with the IAU. This year we are supported by IAU funding and it will help if we can show more UK participation as a result.

People will need three things to participate:

1. A view of the night sky, dark enough to see the Plough

2. A mobile phone with internet connection

3. The url of our website: 100hours.online

Optional extras:

1. Display the Event map (see below) - this webpage is designed especially for use at events. It includes a map, statistics, the url and a QR code. If you display this, your attendees will be able to watch as other people add their achievements. The map is lovely to watch as you can see everyone’s achievements fly in, and sometimes there are even fireworks!

2. Hands-on activities -cheap/easy/branded activities for children 5-12yr that theme in with our 100 Hour challenges .
   

⚠️ Please be aware the 100 Hours activity is not designed to be an entire event all by itself - most people will complete the challenges quite quickly, so the challenges are expected to be run alongside other activities, such as telescope viewing.

VIDEO: Introduction to the event with app and website walkthrough

EVENT MAP

The Event webpage has a fullscreen map with additional information. It is designed for displaying at events, during dark clear skies, during the 100 Hours period. You can embed the map on a webpage by using the following code <iframe src="https://100hours.online/map" height="500" width="100%" title="100 Hours online map"></iframe>

You can zoom in/out as much as you like, click your location, and then just leave the page to auto-refresh every 10 seconds. The map has a lot of dynamic elements to keep interest, with animations that appear as new challenge markers are added.

See the video below for what the map will look like during the 100 Hours, as people all over the country complete challenges.

Please do not share this video with the public - we are not planning to make the map webpage hugely visible to the public, and the voiceover here is just for your benefit. Also we don’t want to advertise the fireworks function too much because it might encourage peope to cheat or feel bad if they can’t complete all four challenges. We will be release a proper sizzle reel of the app on Instagram a couple of weeks before launch, so that will be our main teaser video.

You may also be interested in the IAU’s 100 Hours of Astronomy media kit, which you can download from the Office of Astronomy Outeach’s 100 Hours website. Scroll just over half way down the page to find “100 Hours of Astronomy Box”. These resources do not mention our UK event.

Hands-on Activities

The activities are designed for ages 5-12 yr, although they can be enjoyed by adults too. The activities are all cheap and easy to run. However you will need to do your own risk assessment and ensure adequate supervision is provided. They too are available from our Event Organisers Google Drive space.

The activities include:

1. Pierce cardboard templates to form constellation patterns, using a Pringles tube as a viewer

2. Fold and mark a strip of A4 paper to make a scale diagram of the solar system.

3. Design a mission patch for a space mission - maybe a mission to the Moon?

4. Spot the difference between satellite images (coming soon)

The 100 Hours Under One Sky project is led by the International Astronomical Union (IAU) Office for Astronomy Outreach National Coordinator (NOC) Team for the UK, in partnership with with Ireland NOC, Go Stargazing and support from the IAU Campaign for Dark and Quiet Skies. It is funded by the International Astronomical Union Office for Astronomy Outreach and the Federation of Astronomical Societies. It has also received support from the British Astronomical Association and Royal Astronomical Society.