You will need
- Coloured pens or pencils
- Glue sticks
- Split pins
- Compass (optional, but useful to set the planisphere more accurately)
Make a planisphere
A planisphere is a circular star map that shows the brightest stars and constellations we can see from Earth. It helps you to name the constellations you can see, depending on where you are and what time of year it is.
- Give everyone a set of templates. They should cut out the horizon templates for both hemispheres. They’ll need to cut out the shaded areas in the middle of each template to make the spy window.
- Everyone should fold the tab on the left of each horizon template back behind the template.
- Everyone should glue both tabs, line the horizon templates up with the illustration facing outwards, and use the glued tabs to stick the horizon templates back to back. They should now have a double sided horizon template, which is open all the way through the middle.
- Everyone should use a split pin to make a small hole through the very middle of the double sided horizon template (in the middle of the circle on the bar across the centre of the template).
- Everyone should take their star maps, and use a pencil to write a small ‘N’ for north and ‘S’ for south on the front, before cutting them out. The letters will make sure they don’t get mixed up.
- Everyone should line their star maps up back to back, so that the months line up. It may be helpful to hold the maps up to a light or a window, so you can see through the paper to match up the lines.
- Everyone should pick a month, and place a dot of glue behind their month, on the back of the map. They can then match the month they chose on both maps, to give them a matched up starting point to glue the maps together.
- Everyone should glue their maps together, to create a double sided map – one side is the northern hemisphere, the other side the southern hemisphere.
- Everyone should use the split pin to make a hole in the middle of their star map – it should go right through the north star (Ursa Minor), which is in the middle of the side marked ‘N’.
- Everyone should slide their star map into their horizon template. The side with the ‘N’ on should be under the northern hemisphere horizon template.
- Everyone should line up their star maps, so that the line between the months and the stars lines up with the curved top of the horizon template. The names of some months, and the little numbers underneath, should poke out of the top of the horizon template.
- Everyone should attach the whole planisphere together by pushing a split pin through the holes they made in both pieces earlier. If you’re in the northern hemisphere, this split pin now represents the north star.
Use your planisphere
- Choose the side of the planisphere that matches where you live. If you’re in the UK, you’re in the northern hemisphere.
- Find the right month (and date) on the outside of the star map, and line it up with the time on the horizon template.
- The stars visible in the oval window on your star map are the ones visible in the night sky at that time.
- Why not practice in pairs? One person should pick a date and time, and set their planisphere. They should tell their partner the date and time, and they should set their planisphere, without looking. They should see if the same constellations are visible.
- Once everyone’s confident with their planisphere, it’s time to set it for today, and head outside to see what you can spot in the night sky.
- Make sure the planisphere is set to the right date and time. Start by looking north, and line the planisphere up so north is at the bottom. If you move round, move the planisphere so the direction at the bottom of the horizon template matches the direction you’re facing.
This activity helped you to value the outdoors. Did you enjoy spending time outside looking at the stars? Did it feel different to spending time outside in the daytime? How did looking at the stars make you feel?
This activity also helped you to gain skills. Did you practice doing tricky things like cutting out difficult shapes and using split pins? Did you also learn how to find constellations? Do you know what people throughout history have used constellations for (religious and mythological meaning, remembering the patterns of the stars to predict the seasons, so they knew when to do things such as sowing seeds, navigating, for example by using the north star to find north)?
Supervise young people appropriately when they’re using scissors. Store all sharp objects securely, out of the reach of young people
- Glue and solvents
Supervise young people appropriately when they’re using glue and solvent products. Make sure there’s plenty of ventilation. Be aware of any medical conditions which could be affected by glue or solvent use and make adjustments as needed.
Make it accessible
All Scout activities should be inclusive and accessible.