Assignment+1


 * Ten things I know about the solar system and Earth in space:**

1. There are 8 planets 2. 5 dwarf planets 3. 173 known moons 4. Outer planets have rings 5. Outer planets are also known as Gas Giants 6. the sun is a star 7. Mercury is the closest planet to the sun 8. 200 billion stars 9. Venus is the closest in size to earth. 10. Earth is the densest of the inner planets.


 * Questions 1A-J**

A. The planets rotational period determine the length of one day and one year. B. Seasons are caused by the tilt of the earths rotational axis, away and towards the sun. C. The moon appears to change shape when it orbits around the Earth every 29.5 days. At all times, half of the Moon is lit by the Sun. The other half of the Moon facing away from the Sun is in darkness. As the Moon orbits around the Earth we can see more and more of its lit side. D. A lunar eclipse is caused when when the sun, earth, and moon are aligned almost exactly. The solar eclipse is caused when the moon passes between the sun and earth, so that the sun is almost fully covered. E. In figure 1.1, the points in the night sky are stars, planets, and moons. No, you cannot see them in daytime. F. In figure 1.2 and 1.3, the process that created each landform is erosion. Yes, landforms exist on other planets because there are storms in space. G. Gravity exists every where. Gravity is the strongest on Venus because its the largest planet. Gravity is weakest on Pluto because its the smallest planet. H. The gravitational pull keeps the planets in orbit around the sun. I. Tides are caused by the gravitational force between the earth, sun and moon. J. In figure 1.4, i see a comet in the night sky. A comets "tail" is created when it gets to close to the sun.