A unit overview::
The third grade Astronomy Unit has three main focuses:
~Understanding why the planet Earth has day and night
~Understanding why the planet Earth has seasons
~Becoming more knowledgeable about the planets of the Solar System
A BIT OF A REVIEW:
Day and Night
~ The reason Earth has day and night is because it rotates. It rotates on
its axis at a 23 1/3 degree angle once every 24 hours. The side facing the
Sun experiences day as the side away from the Sun experiences night.
SEASONS:
~ The reason Earth has seasons is because of its tilt as it orbits the Sun.
Because of the Earth's tilt, the hemispheres receive either direct (warmer)
or indirect (cooler)rays of the Sun. When a hemisphere is tilted away from
the Sun it receives indirect rays (winter) and when it is tilted toward the
Sun it receive direct rays (summer).
~The distance of the Earth from the Sun, at anytime during its orbit of the
Sun, has no effect on seasons.
Internet Links
Check on this site each day and see a different image or photograph of our
fascinating universe, along with a brief explanation.
http://antwrp.gsfc.nasa.gov/apod/
Check this site out to find out more about the Sun, it's the Stanford Solar
Center.
http://solar-center.stanford.edu
Want to find out the weather in space today? Click on this site to get the
daily "Space Weather" report!
http://www.sec.noaa.gov/today.html
Find out more about our solar system and galaxy by clicking on this site, a
learning center for Young Astronomers.
http://starchild.gsfc.nasa.gov/docs/StarChild/StarChild.html
Go to this site to find out about the Mars program.
http://marsprogram.jpl.nasa.gov/
Other Resources