BACKGROUND:
The Universe is everything students see in the night
sky, and more that they don't see! Remember students do not have to
understand objects such as planets, stars, and galaxies. It is enough that
they can begin recognizing the components of the Universe. Current evidence suggests that there is only one Universe that has evolved over the last 15
billion years. There are many doubts about specific "facts" on the
Universe because it is "untouchable" by humans.
The Universe is the big picture; every component
within the Universe (like the stars) is a subset. The Universe is not empty,
but is full of dynamically evolving objects. Stars can be considered
"burning" gases of helium and hydrogen that give off heat, light,
and plasma. Plasma is the most abundant form of matter in the Universe; it
can be explained as free electrons in an excited energy state. The
"glow" in a fluorescent light bulb is an example of plasma. Stars
have a life cycle; they are born, burn for millions to billions of years,
and eventually die out.
Other objects in the Universe include galaxies,
nebulas, dark matter, other solar systems, asteroids, and comets. Stars that
are close together and rotate as a unit are called a galaxy. Our Sun is part
of the Milky Way Galaxy. A nebula is a cloud of gas and dust. Nebulas may
form when stars explode as supernovas. Stars may also be "born" in
nebulas. Asteroids are chunks of rock left over from the formation of the
Solar System. Similarly, comets are balls of ice and minerals left over from
the creation of the Sun and planets. We see them glowing in the night sky
when they orbit close to the Sun and heat up, throwing off glowing tails. A
solar system is an arrangement of planets around a central star or stars.
Our Solar System includes the Sun, the nine planets, their associated moons,
and countless asteroids and comets. There have been mathematical
observations of other planetary systems in the late 1990's. Dark matter is
just what it sounds like: material that is not visible by ordinary means.
Astronomers hypothesize that dark matter exists because their work suggests
that too little visible matter exists to account for the gravity and mass of
the Universe.
PROCEDURE:
- This lesson starts your students on a voyage to understanding the
Universe. They have seen the night sky and they probably have always
asked questions about the sky. You may want to start this lesson with
some oral communication skills. Ask the students to tell the class what
they think is in the night sky. You may want to list some of their key
observations which should include stars, moons, twinkles, and sometime
even UFO’s!
- After the discussion on what the children have observed, describe the
Universe for students. Emphasize that we are still learning about what
makes up the Universe. We are far from knowing everything about it. You
may wish to explain that facts and figures about the Universe are
subject to change with new information from astronomers.
- Read the students a book on stars. We recommend The Sky is Full of
Stars. It reinforces the discussion on the night time sky and puts
the facts into an understandable story. Note to students that stars are
not "star shaped." A star appears to twinkle, and hence
star-like, because of atmospheric disturbance of light that we see (and
some other factors.)
- Use the worksheet to reinforce the different larger components of the
Universe. Students can color and use their imagination.
