Wednesday, July 29, 2015

Learning through Play: Galaxy Art

Learning through Play: Galaxy Art

Discover some of the beauty and mystery of the universe, exploring photographs taken from telescopes and exploring the science behind these pictures.  Learn about the electromagnetic spectrum.  Compare the shapes of galaxies or the shapes seen in constellations.

The Projects
These projects are great for a variety of ages.  Children of all ages should enjoy the first and love the images.  The second project is also good for many ages, but the science information can be a little difficult for young ones to understand.  The final project may require adult supervision but the final project is nice for many ages.

You will need bowls, shaving cream, glue, spoons or craft sticks, various colors of liquid watercolor, eye droppers, paintbrushes or coffee stirrers and black paper.  You will also need clear plastic page protectors, permanent markers, lithographs or photographs of the galaxies and nebulas.  Additionally, you will need a Pringles can or small paper cups, a hammer and ice pick or nail or an unfolded paper clip, construction paper, scissors, glue, markers, and décor.

Before beginning the projects, check out some images of galaxies and nebula.  You can get some free by visiting or writing to your local ERC (Educational Resource Center) run by NASA.  These often include some information about what you are looking at.  Additionally, some web images to explore:


To prepare for the first project, mix shaving cream and a small amount of glue in a bowl.  The glue will help the shaving cream keep some of the foamy texture as it dries.  The amounts of glue to shaving cream will vary depending on brands used.  Using the pictures of galaxies and nebula as inspiration, use a craft stick to spread the shaving cream onto the black paper into the basic shape you desire.  Use the eyedropper to add drops of color to the shaving cream and use coffee stirrers or craft sticks to spread the colors.  Explore how the colors combine.  Paint brushes can be used in this activity, but fair warning, when paint brushes are used with glue it can make the brushes very stiff.

When white light is broken up, it produces a spectrum of colors that we call the rainbow.  The electromagnetic spectrum is an even bigger version of this concept, with visible light as only one small part of this spectrum.  Sometimes NASA uses this full electromagnetic spectrum to create an image.  They assign different colors to different wavelengths of light.  Place one of the pictures of a galaxy or nebula under the clear plastic page protector and mark where the corners are.  Look for reds, greens, or blues in the image.  Start with red, and wherever you see red create a series of small red dots with the permanent marker in this area.  When you have finished with red, place a new clear page over the picture and mark the corners on this one as well.  This time create a series of blue dots over the blues in the image.  Finally, place the last clear page over the image, mark the corners, and create a series of green dots over the green in the image.  Place all three pages over each other and examine the image you have created.  Feel free to add where you feel the image needs it to make it look more like the original picture.  How does the final image change as each color is added or removed?

This is similar to the method NASA scientists use to create many images.  Real-color images are seen as we would see them, but many other images are combinations of satellite pictures representing different chemicals in the galaxy of the unseen wavelengths of the electromagnetic spectrum.  Sometimes light is broken down into short infrared shown as blue, intermediate infrared shown as green, and long infrared shown as red.  In the Cat’s Eye Nebula, light from hydrogen atoms might be shown as red, oxygen atoms as blue and nitrogen atoms as green.  In the Eagle Nebula, light from hydrogen atoms is shown as green, sulfur ions as red, and doubly-ionized oxygen as blue.

The last project looks to the constellations.  Constellations are like playing connect-the-dots in the sky.  Many ancient civilizations looked to the sky and created stories around the images they saw.  Some famous simple examples are Cygnus, the dippers, Cassiopeia, or Cepheus.  If you are working with younger children, use paper cups and a paper clips.  Older children may be able to handle a Pringles can and nails.  After exploring some of the constellations, use the paperclip or nails to punch holes into the bottom of the cup or can in the design of your choice.  You may try to copy existing constellations or create your own.  Decorate the outside of your tube as you wish, but if you copied an existing constellation you may want to make sure to label it to help you remember.  When the tube has dried, look through the open end and notice how the light shines through where the stars would be.

Some Information to Share
A long time ago, astronomers would classify galaxies and clusters of stars as nebula, because they couldn’t tell the difference.  Scientists today have better ways of viewing space, and thanks to astronomers like Edwin Hubble, have better ways of classifying galaxies and nebula.  A galaxy is bound together by gravity and might contain planets, dust and millions of stars.  We live in the Milky Way galaxy.  Edwin Hubble started sorting galaxies into spiral, barred spiral, elliptical, and irregular shapes.  The Milky Way Galaxy is a spiral galaxy, and our solar system is about two-thirds to the way out in one of the arms of the spiral.  The Milky Way is in a group of galaxies known as the local cluster.

A nebula looks like a cloud in space and is full of dust, hydrogen, helium, and other gases.  The hydrogen inside can make a nebula look red while dust makes it glow blue.  Nebulae are created when stars like the Sun run low on hydrogen fuel.  They puff into a planetary nebula, like the Cat’s Eye Nebula, which many early astronomers thought was a planet.  Other nebulae are created from the death of giant stars, exploding in a supernova.  The core of the star either creates a neutron star or a black hole, but the extra material thrown off creates a supernova remnant like the Crab Nebula.  The supernova creating the Crab Nebula was noted by astronomers in the year 1054.  Under the right conditions, a nebula may become a star nursery.  When the dust, gas, and other material clump together, they may form larger masses, which attract more matter and over time grow large enough to form stars.  The Orion Nebula, near Orion’s Belt, is a great example of this.  The Crab Nebula has the Crab Pulsar inside, which is a young star that sends out radio waves.  The Eagle Nebula, shown in the famous image by NASA of the Pillars of Creation, is also a great nursery.

The electromagnetic spectrum is the grouping of types of radiation organized based on their wavelengths.  Some of these are capable of traveling through the Earth’s atmosphere while others are not.  From largest to smallest, there are radio waves, microwaves, infrared, visible light, ultraviolet, x-ray, and gamma rays.  We know how to break down visible light into different wavelengths using a prism to create a rainbow.  Red light has the longest wavelength while violet has the shortest.  When NASA creates representative color photographs, they use satellites to record some of this spectrum that we can’t see.  They then can assign colors to these wavelengths and create a composite image.

Many ancient civilizations like the Sumerians and Greeks created stories about the pictures they saw in the sky.  Sometimes, the stories explained why the picture was in the sky and sometimes they just helped people remember the constellation.  Since there were many different groups of people making pictures in the sky, scientists today decided to pick 88 official constellations so that everyone uses the same pictures.  These astronomers can then use the position of these official constellations to help record other objects they find in the sky.  Ancient people used the constellations in a different way. They could use the stars to study the seasons, like the ancient Egyptians using Sirius to note when the Nile River would flood.  They could also use the North Star to find north, helping guide their way.

Bibliography
stars.astro.illinois.edu/sow/const.html, comfychair.org/~cmbell/myth/myth.html
www.utahskies.org/constellations/

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