Guest post by Erin Votaw, GSC Educator
Hello my preschool science buddies! If you aren’t familiar with Nature Tots programs at the Greensboro Science Center, let me introduce myself. My name is Erin and I am a part of the Education department here at the Greensboro Science Center. I have been teaching Nature Tots classes, summer camps and grant programs for the past 10 years. I thought it may be fun to investigate some of the topics we didn’t get to meet up for in our Nature Tots class. We always have such a fun time together on Tuesdays and I look forward to the time when we get back to the fun, together in our special place with visiting animals and keeper talks. The GSC is working hard to keep the animals happy but I know they miss seeing your sweet faces checking on them.
What makes the night sky twinkle? Such a great question that begs for an answer. Let’s begin with stars and how they work. We see our sun, the center of our solar system every day, and especially when it’s a nice sunny day. The largest star in our solar system, our sun gives us light, warmth and life to Earth and plants through the process of photosynthesis. Made of helium and hydrogen gases held together by gravitational pull, the sun is the reason for our seasons, weather and – let’s be honest – birthdays! Your birthday comes from each revolution around the sun. Sounds like a very important star to me! And at around 6000℃, wow! Talk about hot!!!
Have you ever seen a helium balloon? Maybe at a birthday or graduation party or just floating in the sky? The helium inside the balloon is an invisible gas that makes it float and is one of the same invisible gases that creates the stars in our sky. Stars are actually giant balls of gases, like helium and hydrogen, that are so hot and fiery that they glow brightly and give off heat. Stars do come in all sizes but they are so far away from us that they look like tiny, beautiful, twinkling points of light, when actually they are really gigantic!
Stars can also be different colors depending upon how hot they are. The coolest temperature stars are red, warmer stars are yellow-orange, hot stars are white and the very hottest stars are blue! We can’t actually feel the heat from the smaller stars because they are so far away.
Let’s try to see if we can see this for ourselves. Gather up some colored tissue paper and a flashlight. Turn down the lights. Using your flashlight and colored tissue paper, cover the light part of the flashlight with the tissue paper. What color is the light from the flashlight now? Try different colors. Shine the light onto the walls. Can you see how the color of the light changes for the tissue paper color? Just imagine you are changing the temperature of the star based on the color of tissue paper you put over the light.
Stars also shine all the time! It’s difficult to understand this because we do not see them during the daytime. This is because the light from the sun is so bright that it is impossible to see the light coming from the other stars. But really, we do see one star during the day – the sun!
So, onto the question of twinkling. Just how do the stars twinkle in the sky at night? The stars twinkle in the night sky because of the effects of our atmosphere. When starlight enters the atmosphere it is affected by wind, temperature and density. These fluctuations in the stability of the air and changes in properties in the atmosphere causes the light from the star to twinkle when seen from the ground. Think of it like this – as the light travels to where we can see it (from deep, dark space down to our eyes on Earth), it passes through things that cause it to jumble like a car on a bumpy highway. Not super smooth, but bumpy and jumpy, hence the twinkling appearance of the light when we finally see it. Goodness, I just like thinking that they were blinking at us!
A group of visible stars that form a pattern we can see is called a constellation. Scientists who study space have given many stars and constellations names and you can look for them in the night sky. You may have heard of the North Star and constellations like the Big (and Little) Dipper, Orion and the Northern Cross just to name a few. A great way to investigate stars and constellations is to check out the sky at night. There are several free apps for your phones that allow you to “look” at the sky and know what you’re actually looking at in the sky. Fascinating really!
We can make our own constellations in a couple of fun ways. Using a piece of construction paper, star stickers (or whatever you have on hand) and white chalk or crayon, we can lay out a shape or design for our constellation. Place the stickers in a square (or whatever shape you want) on the paper. Next, draw lines with the chalk to connect the stickers and there you have your very own constellation!
Another option is to use a tp roll and make it a constellation viewer. Take the tp roll and put a square of construction paper over one end with a rubber band. Ask an adult to help you poke holes with a toothpick (in a shape or constellation design) through the construction paper.
Hold it up to the light and you will be able to see your constellation design. What will you name your constellations? Very stellar!!
Stars and space are super interesting areas to learn about and investigate. I would recommend you get outside and check out space in your place. Go out during daytime to look at the clouds and the light (don’t look directly at the bright sun…ouch!). Peek outside at night to see if you can see the stars twinkling — can you connect them to make constellations? You may even have seen the space station fly overhead recently! Seriously, space is FULL of neat science.
Be sure to observe the moon during its phase changes and maybe make a 30-day moon chart (you can check the internet for a sample). A fun read to go along with this moon shape study is the story “Breakfast Moon” by Meg Gower. It corresponds to a family journaling the moon’s shape with shapes of their foods at breakfast. How sweet!!
I hope to bring you more blogs and activities to help keep you engaged in our science world. I hope to see you again soon, until then have fun and remember science is everywhere!