Test Review- 1/25/11
The Phases of the Moon-Different Faces in the Night
New Moon-When the moon is in between the sun and the Earth, we cannot see the moon. This part of the moon is in the shade. Waxing Crescent Moon -"Waxing" means growing and refers to the size of the illuminated part of the moon that is increasing.
First Quarter Moon-When the moon is above or below the Earth, we can only see half of the lit area of the moon.
Waxing Gibbous Moon -A gibbous moon is between a full moon and a half moon, or between a half moon and a full moon.
Full Moon-When the Earth is in between the moon and the sun, we see the whole part of the moon which is lit up by the sun.
Waning Gibbous Moon -"Waning" means shrinking. When the the Moon is said to be waning, we see a little less of the Moon each day until it completely disappears when the Moon is New
Last Quarter Moon
Waning Crescent Moon-When the moon is in between the new moon and the half moon, we are only able to see a little sliver of the lighted side of the moon.
As the moon grows larger, towards becoming a full moon, it is called a waxing moon.
As the moon grows smaller, away from being a full moon, it is called a waning moon.
Seasons
Rotation vs. Revolution Rotation is the spin of an object about its axis. o The Earth rotates once a day (once every 24 hours). Revolution is the orbit of one object around another. o The Earth revolves around the Sun every 365.26 days. Solar Heating o The sun or any light, heats a surface most effectively when it is shining directly onto the surface.
What Causes Earth’s Seasons? o Earth’s axis is tilted 23.5 degrees – it always points in the same direction (Polaris, the North Star) as we orbit our Sun once a year o This tilt causes the hemispheres to alternate in the amount of our Sun’s light and heat they receive through the year.
Seasons o o o o Seasons o
o o o o
o o Equinox o o o o o o Solstice o
vs. hemispheres Northern and southern hemispheres have reversed seasons. In summer, the sun is at a smaller angle,more effective heating. In winter, the sun is at a larger angle, less effective heating. Misconception Many people carry the misconception that the seasons are due to the distance of the Earth from the Sun. However, consider the following facts: The Earth’s orbit around the Sun is nearly a perfect circle. The Earth is slightly closer to the Sun in January and farther from the Sun in July. Perihelion (closest to the Sun) is around January 3 when Earth is about 91,405,436 miles from the Sun. Aphelion (farthest from the Sun) is around July 4 when Earth is about 94,511,989 miles from the Sun. While it is winter in the Northern hemisphere it is summer in the Southern hemisphere. If the seasons were due to our distance from the Sun both hemispheres would have the same seasons at the same time. Earth’s orbit is almost a perfect circle Sun rises due east Sun sets due west Exactly 12 hours of day, 12 hours of night Once in spring Once in fall When the sun is directly over the equator.
Summer solstice:
o
Winter solstice:
Longest daylight off the year Sun at noon is highest in the sky Shortest daylight off the year Sun at noon is lowest in the sky
Heat Transfer o The movement of heat from a warmer object to a cooler object. Conduction o Heat transfer by direct contact of molecules. In other words, when one molecule runs into another and it runs into another, etc. o It can occur in a solid, liquid or a gas. Occurs best in a solid because the molecules are close together. Convection o Heat transfer by means of up and down movements called convection currents. o Can occur only in a liquid or a gas Convection currents o Heated molecules do 2 things: they expand, become less and then they rise. o Cooled molecules do the exact opposite: they contract, become more dense and then they sink That is what makes a hot air balloon rise. Radiation o Heat transfer through open space. o Occurs in a gas only