Moon Phases

Waxing moon: the moon is getting visibly larger, going from a new moon to a full moon

Waning moon: the moon is getting visibly smaller, going from a full moon to a new moon

Gibbous moon: when the moon is more than half full but not fully illuminated

Crescent moon: when the moon is less than half lit but not completely a new moon

Patterns of Moon Phases

Pattern of a Waxing Moon: Will become more illuminated each night until it reaches a full moon.

Pattern of a Waning Moon: Will become less illuminated each night until it seams to fully disappear into a new moon.

Lunar Cycles

A lunar cycle is the moon's continuous orbit around the Earth. Each lunar cycle takes approximately 29 days.

Earths Seasons/Eclipses

Copernicus was an astronomer that discovered the sun was the center of the solar system was the sun, not the Earth.

We have seasons because the Earth orbits the Sun elliptically ,and at the same time, spins on an axis relative to its plane of orbit.This means that different hemispheres are exposed to different amounts of sunlight throughout the year which effects the heat and weather that gives us seasons.

In the winter, when the sun is closer to the Earth, it isn't warmer because our hemisphere is not facing the sun. So it makes it warmer in the other hemisphere.

There are not lunar eclipses each month because the Moon's orbit around Earth is slightly inclined with respect to the ecliptic, solar and lunar eclipses do not occur every month, but only a few times per year.

We have day and night because the Earth spins. When the Earth spins there is a period where the side you are on is not facing the sun. At this time it is dark and the only thing lighting the night sky are stars and the moon (if they are showing). This time is night. When the side of the planet you are on is facing the sun it is daytime.

Equinox-The vernal equinox and autumnal equinox herald the beginning of spring and fall, respectively. At these times of the year, the sun appears to be directly over Earth’s equator, and the lengths of the day and the night are equal over most of the planet. When the Northern Hemisphere is having spring the Southern is going through an autumnal equinox.

Solstice-A solstice marks the points at which the poles are tilted at their maximum toward or away from the sun. This is when the difference between the daylight hours and the nighttime hours is most acute. The solstices occur each year on June 20 or 21 and Dec. 21 or 22, and represent the official start of the summer and winter seasons.

Plate Tectonics

Alfred Wegener was a German polar researcher, geophysicist and meteorologist. During his lifetime he was primarily known for his achievements in meteorology and as a pioneer of polar research, but today he is most remembered for advancing the theory of continental drift (Kontinentalverschiebung) in 1912, which hypothesized that the continents were slowly drifting around the Earth.

Convergent boundaries- When continental and oceanic plates collide the thinner and more dense oceanic plate is overridden by the thicker and less dense continental plate. The oceanic plate is forced down into the mantle in a process known as "subduction". As the oceanic plate descends it is forced into higher temperature environments.

Divergent boundaries- When a divergent boundary occurs beneath oceanic lithosphere, the rising convection current below lifts the lithosphere producing a mid-ocean ridge. Extensional forces stretch the lithosphere and produce a deep fissure. When the fissure opens, pressure is reduced on the super-heated mantle material below. It responds by melting and the new magma flows into the fissure. The magma then solidifies and the process repeats itself.

Transform boundaries- Transform faults can be distinguished from the typical strike-slip faults because the sense of movement is in the opposite direction (see illustration at right). A strike-slip fault is a simple offset, however, a transform fault is formed between two different plates, each moving away from the spreading center of a divergent plate boundary.

The plate just off the coast of Washington is the Juan de Fuca plate.

One important aspect that changed late in the Cascade Episode was the status of the northern end of the Juan De Fuca Plate, a portion now known as the Explorer Plate. Between 5 and 7 million years ago, the Explorer Plate broke off from the Juan De Fuca Plate, along a transform now known as the Nootka Fault. This change apparently had some important ramifications for regional geologic evolution. When this change was completed, Cascade Arc magmatism returned and the modern Cascade and Olympic Ranges started to rise.

The Earth's mantle has convection currents because the heat of the core acts similarly to the light bulb in our lava lamp. The core's heat energy is transferred to the mantle, causing it to rise towards the Earth's surface, which is cooler. As the heated mantle transfers its heat energy to the lithosphere, it becomes more dense than the surrounding magma and sinks back down towards the core.

A rift zone is a feature of some volcanoes, especially shield volcanoes, in which a linear series of fissures in the volcanic edifice allows lava to be erupted from the volcano's flank instead of from its summit.

The subduction zone is the place where two lithospheric plates come together, one riding over the other. Most volcanoes on land occur parallel to and inland from the boundary between the two plates.