The Globe at Night activity, measuring light pollution by looking at Orion, is a great activity for you to do with your kids. It only takes 5 minutes IF you prime them a bit. Here’s what worked great with me and my kids (aged 7 and 10).
I printed out the “family pack” at Globe at Night and left the 2 pages with 8 star charts on the kitchen counter. I asked my kids to look at them and think about the pattern in the 8 charts, “…but don’t tell me yet,” because one always talks for the other!
After a minute or two (while I finished doing the dishes), I asked them one by one what they saw. (“No, be quiet now and let your brother talk!”) They loved that the first chart, with nothing, meant there are clouds. Ha-ha! Unfortunately, they carried that along and thought that the difference between the remaining charts was how many clouds there are. So watch for it, and get them thinking about light pollution (but don’t mention it, yet!) “Remember when we went camping and saw that amazing sky? What was the difference between that and our backyard?” Hopefully, they start talking about how you can’t see the stars in the city because it’s too bright. Bingo!
Now you tell them Globe at Night is a way to figure out how much light pollution there is here (in my case, in Vancouver) — around the World! By doing this in our backyard, we’re helping people all around the World to do a real, live, scientific experiment!
Almost ready to go outside. Look closely at the charts with your kids and identify what stars appear as you go to the next chart (higher magnitude, darker sky). This will help you determine which chart matches your sky. For example, first you can only see 2 belt stars. In the next chart, 3 belt stars. In the next, you can see Orion’s “head”. In the next, you can see a curved shield, and so on. These specific markers/signposts help you choose the chart that best matches your sky.
Alright, bundle up the kids and head outside. Bring the charts and, if you’ve got one, a red light. We have a key chain with a red LED that worked great. By the time we walked to a dark spot in the backyard (where the neighbours’ yard lights weren’t shining on us) and found Orion, our night-vision was pretty good. The kids easily spotted the 3 stars of Orion’s belt but I made sure to ask them how many stars they could see and then showed them the charts so we could all agree the sky was definitely at least Magnitude 3. Now we looked specifically for Orion’s “head”, the star above his shoulders. They looked waaaay too high, up to, what’s that, anyway, Capella, maybe, because we’re all naturally drawn to the bright stars. Point to the star chart and look at the shape of the triangle formed by Orion’s shoulders and head. A short triangle, only about half as tall as it is wide. This got them looking at the right place in the sky. Remember, you’re only going to make a decision when you can’t see something, so you have to look at the places where it’s hard to see the stars.
For us, it was a simple, conclusive test: “Can you see Orion’s head, yes or no?” Both kids, and even me with my too-much-time-on-the-computer damaged eyes, could see it. Great – we’re at least Magnitude 4. Now look for the curved shield. Can you see that, yes or no? “Yeah, way over there,” he squealed, pointing to all the nice, bright colourful stars in Taurus’ face. Okay, back to the chart: the shield is halfway between Orion and those stars. Sadly for us, no, we couldn’t see the shield. That nailed it – our sky was the Magnitude 4 chart. We filled out the Observation Sheet when we got back inside.
The next night (it was getting late and time for bed, after all) we submitted our report online at globeatnight.org. The GUI is nice because it looks just like the paper observation sheet so they could easily transfer our paper-and-pencil notes onto the computer. Then we had a lot of fun looking at the map of everyone else’s observations. It starts by showing the entire globe at night (imagine that!) Like google Earth, the map is zoomable so we zoomed right down to our neighbourhood, and discovered someone just a few blocks away had submitted a report! The kids thought it was pretty cool that our dot would be on the map, too.
The thing to remember is, compared to our kids, spacetweeps are experts at reading maps and realizing that it’s the differences between the star charts that matters. Without some guidance, kids may not see this critical feature – they’re still imagining Orion swinging his sword. Our job here is not to tell them what the answer is; rather, it’s to shepherd them to the answer (or at least, “an” answer?) by providing the tools and support to use them. And, most importantly, being crazy-excited and super-ethusiastic about going outside to see the stars and doing something scientific.
Happy globe-at-night-ing, spacetweeps.