Good afternoon 4B Space Scientists!!  Please, read through the Bellwork slide & the “Coming Up” slide Note: you have a content check-in quiz on Monday 10/22 Use the rest of the slides to fill in the note sheet provided (white paper) Then, you will be

Bellwork 10/16 What do each of Kepler’s laws say? Why are Kepler’s Laws significant to the understanding of the solar system? How might understanding Kepler’s Laws be useful in future space exploration…either in our Solar System or beyond?

Coming Up: Today: Thursday 10/18 Monday 10/22 Wrap up Kepler’s laws Begin discussing Moon Features Begin Moon Formation Theories Thursday 10/18 Moon Formation Theories “Stations” Monday 10/22 Short Check-in quiz Nebular Hypothesis, Classifying Space Objects, Kepler’s Laws Finish Moon Formation Lunar Cratering Simulation

Today we’re looking at a very specific member of our solar system Our goal over the next few days is to understand the Moon’s features and how it formed.

Our Goal Today & Thursday How did the moon form? We will look at 4 different theories One theory is accepted as the best…though there are certainly still questions… I want you to look at the other 3 to understand why Appreciate the process as to how scientific theories change…science doesn’t “get it right” immediately…

Earth's Moon General characteristics Diameter of 3475 kilometers (2150 miles) is unusually large compared to its parent planet Density 3.3 g/cm3 Less dense than Earth, but… Composition similar to Earth's crustal rocks Perhaps the Moon has a small iron core (?)

Earth’s Moon Gravitational attraction is one-sixth of Earth's No atmosphere Tectonics no longer active Surface is bombarded by micrometeorites from space which gradually makes the landscape smooth

Our “two-faced” Moon… Lunar Maria Lunar Terra

One other interesting thing about our moon… This is unusual because The moon is quite close to the Earth Many planets (much farther away) travel within a much closer degree of tilt

Craters on the Moon Large crater basins (seas) were created by HUGE impactors moving very FAST What might that tell us about the formation of the moon? Smaller craters are created from meteoroids which produces Ejecta Occasional rays (associated with younger craters)

Major topographic features on the lunar surface

Lunar Surface Two types of terrain Maria (singular, mare), Latin for "sea" Dark regions lowlands Originated from asteroid impacts and lava flooding the surface

Formation of lunar maria

Lunar Surface Highlands (Terra) Bright, densely cratered regions Make up most of the Moon Make up all of the “far" side of the Moon Older than maria

Lunar Surface Lunar regolith Covers all lunar terrains Gray, unconsolidated debris Composed of Igneous rocks Breccia Glass beads Fine lunar dust "Soil-like" layer produced by meteoric bombardment

Now, obtain the “Moon Formation” station packet (blue paper) Record the information on the next slide on the appropriate spot on the blue packet (front page)

How did the moon form? Let’s find out… Two challenges a lunar formation hypothesis must address: Why is the Moon much less dense compared the Earth & why are their compositions different? Why is the Moon’s inclination to the Earth tilted the way it is?