Today we will be learning about: Welcome Back! Today we will be learning about: The features of the moon Small solar system objects

What is the moon like? The surface of the moon is not flat and smooth. When Galileo first viewed the moon from his telescope in 1609, he was amazed to find a unique and varied surface, similar to Earth’s

Maria (MAH ree uh) Maria: hardened rock formed from huge lava flows. These occurred 3-4 billion years ago. The singular form is called a mare. On the surface of the moon, maria appear as dark flat areas. They even have different names.

Craters Craters: large round pits caused by meteoroids. They can be hundreds of kilometers across. Meteoroids are chunks of rock or dust from space

Highlands Highlands: appears as light-colored areas on the surface. These can be like plateaus or mountains. The peaks and rims of craters cast dark shadows on the surface. The highlands cover most of the moon’s surface.

Other aspects of the moon Size: about as far across as the United States (3,476 km) Temperature: 130° C in direct sunlight (266° F), -170° C (-274° F) at night. There is very little water, but it can be found close to the surface

Small objects in the solar system Although there are many large objects in the solar system like the sun, moons and planets, there are millions of smaller objects floating around within the reaches of our sun’s gravitational field.

Dwarf Planets The most famous is Pluto (demoted in 2006) Others include Eris, Makemake, Humea, and Ceres. These dwarf planets have moons of their own, some almost as big as their parent planets

Comets Comet: a loose collection of ice, dust, and small rocky particles whose orbits can be very long, narrow elipses. Most originate from the Oort cloud. The comet’s tail comes from the gases and ice heating up when it approaches the sun.

Anatomy of a Comet

Asteroids Irregularly shaped chunks of rock. Most are less than a kilometer across. Scientists have discovered over 100,000 asteroids in the solar system, and we are still finding more. Most are found in the asteroid belt.

Meteoroids Chunks of rock or dust generally smaller than an asteroid (less than 10 meters across). Meteor- when a meteoroid creates a streak as it enters the atmosphere. Meteorite- when a meteoroid comes in contact with the surface, often leaving a crater.