DO NOW: 1.Start to work on word search

1 – Where are you in the universe 2 - How does human life fit into the time scale of the universe? 3 –Why should you study astronomy? 3 ESSENIAL QUESTIONS

Astronomers use the metric system because it simplifies calculations and use scientific notations for very large or very small numbers Our solar system consists of the sun, its family of planets, and some smaller bodies, such as moons and comets Planets are small, spherical, nonluminous bodies that orbit a star and shine by reflected light like Earth, Venus, and Mercury The sun is a star, a self- luminous ball of hot gas that generates its own energy Where Are You?

Average distance from Earth to the sun is a unit of distance called the astronomical unit (AU) = 1.5 x 10 8 km Distance from Venus to the sun is about 0.72 AU Light reaches earth in 8 minutes but it takes over 4 hours to reach Neptune Where Are You?

My Very Educated Mother Just Served Us Noodles List out the planets 1)5) 2)6) 3)7) 4)8) Where Are You?

To express large distances use light years (ly) – distance light travels in one year about km or 63,000AU Light year is a unit of distance and not a unit of time!!! Where Are You?

A galaxy is a great cloud of stars, gas, and dust held together by the combined gravity of all of its matter Range from 1500 to over 300,000 ly in distance Some contain over 100 billion stars Our galaxy is Milky Way Galaxy *what we see when we look up at the sky is the string of stars that make up the Milky Way Where Are You?

How can we know what the galaxy looks like? Astronomers use evidence to guide their explanations - artists then use scientific descriptions to create a painting Where Are You?

Our galaxy like other has spiral arms. Long, spiral pattern of bright stars, star clusters, gas, and dust A century ago astronomers thought it was the entire universe – now we know that our galaxy is only one of many billions of galaxies Where Are You?

Gives us perspective on what it means to be on Earth Not only does astronomy locate you in space and time it places you in the physical processes that govern the universe *Gravity and atoms work together to make stars, light the universe, generate energy, and create chemical elements in your body We are very small and have only existed in the universe for a short time Why Study Astronomy?

1.List two things that we discussed yesterday about science 2.What is the difference between our solar system, our galaxy, and the universe? Summary Questions: