Quiz 1 Study List s1

Quiz 4 Study Guide Earth in Space - 8th Grade Science – Miss Fox Refer to your Science Journal Some analysis, and activities from class will be on the Quiz!

Scientific Skills: Hypothesis - A tentative theory used to explain a set of facts. A hypothesis can lead to further investigation to test whether the hypothesis is valid (predication/educated guess). Variable - A factor in a scientific experiment that can vary. Controlled variable - A variable in an investigation or experiment that is held constant. Observation - Any description or measurement gathered by the senses. Data- Information gathered from an experiment. First-hand evidence from the five senses or from machines that extend our senses. Reproducible - An investigation that can be repeated to give the same or similar results. Model - Any representation of a system, or its components, to help one study and understand how it works. Plausible - Consistent with evidence. Angle - A measure of how much two lines diverge.

Astronomy – is the study of objects and events beyond Earth’s atmosphere. Phenomenon - An event, or something that happens, in the natural world or universe. Big Bang - is the explanation for the origin of the universe; a rapid expansion and cooling that scattered energy, formed matter, and created space itself, approximately 13.7 billion years ago. Earth formed approximately 4.5 billion years ago. The sun is the closest star to Earth and there are 7 other planets in our solar system (8 including Earth). Rotate/Rotation - To turn or spin around an axis. Earth rotates counter clockwise. Axis - The imaginary line around which objects spins, or rotates. Earth rotates around an axis that runs through Earth from the North Pole to the South Pole. Earth is tilted at 23.5 degrees on its axis.

Hemisphere - One half of a sphere. The half of Earth that is north of the equator is the Northern Hemisphere; the half of Earth that is south of the equator is the Southern Hemisphere. Equator - An imaginary circle that divides Earth into two halves called the Northern Hemisphere and Southern Hemisphere. Latitude – is the distance in degrees of a location north or south of the equator.

Altitude – is the elevation above sea level. Elevation – is the height of a location above sea level. Day & Night -The change between day and night is caused by the rotation of the Earth on its axis. The changing lengths of days and nights depends on where you are on Earth and the time of year. Also, daylight hours are affected by the tilt of the Earth's axis and its path around the sun. A solar day, 24 hours, is the time it takes for the Earth to rotate exactly once so that the sun appears at the same place in the sky the next day.

The sun appears to move across the Earth's sky because of Earth's rotation. As Earth turns on its axis, an observer on the surface sees the sun appear to come up somewhere over the eastern horizon, rise to a peak around midday and then begin its descent toward the west. This cycle varies slightly from one latitude to another, as well as from one day to another.

A sundial is a device that tells the time of day by position of the Sun in the sky. As the sun appears to move across the sky, the shadow aligns with different hour-lines, which are marked on the dial to indicate the time of day.

Time zone - Regions that share the same standard time. Time zones tend to follow the boundaries of countries and their subdivisions. The first adoption of a standard time was in 1847, by railroad companies in Great Britain, due to the confusion between times in different locations and the need to standardizes times to improve service and communication.