Earth's Tilted Axis Practice Flashcards

Vocabulary-style flashcards covering the concepts of Earth's axial tilt, seasonal patterns, solstices, and equinoxes based on the lecture material.

Pattern

Something that happens in a regular and repeated way, such as the yearly cycle of temperature changes.

System

A set of connected parts that form a complex whole, such as the Earth-sun system.

Earth's Axial Tilt

The angle of Earth's axis, which is not perpendicular to its orbital plane and is tilted approximately $23.5^\circ$.

Solstice

A time of the year when the North or South Pole is closest to the sun during noon.

Equinox

A time of the year when the sun is directly overhead at the equator during noon.

Tropic of Cancer

The northern tropic located at $23.5^\circ\text{N}$ that receives direct sunlight during the June Solstice.

Tropic of Capricorn

The southern tropic located at $23.5^\circ\text{S}$ that receives direct sunlight during the December Solstice.

Direct Sunlight

Sunlight that strikes Earth's surface at a $90^\circ$ angle, also known as a perpendicular angle.

June Solstice

The day marking the start of summer in the Northern Hemisphere and the start of winter in the Southern Hemisphere.

December Solstice

The day when the South Pole is closest to the sun and the Tropic of Capricorn receives the most energy.

September Equinox

The time of year marking the first day of autumn in the Northern Hemisphere and the first day of spring in the Southern Hemisphere.

March Equinox

The time of year marking the first day of spring in the Northern Hemisphere and the first day of autumn in the Southern Hemisphere.

Equator Latitude

The location on Earth designated as $0$ latitude which receives sunlight at a perpendicular angle during equinoxes.

Concentrated Light

Light that transfers more energy because it is not spread out, occurring when the light source is perpendicular to a surface.

Diffuse Light

Light that is spread over a larger area when it hits a surface at an angle larger than $90^\circ$, transferring less energy per spot.

Northern Hemisphere Winter months

The months of December, January, and February.

Northern Hemisphere Summer months

The months of June, July, and August.

Chicago Sun Exposure in June

The sun travels an arc high in the sky and remains visible for about $15$ hours.

Chicago Sun Exposure in December

The sun does not rise as high above the horizon and stays in the sky for a little more than $9$ hours.

Tropics

The latitudes furthest north and south ($23.5^\circ\text{N}$ and $23.5^\circ\text{S}$) that receive direct sunlight during solstices.

Stonehenge

An ancient structure with rocks aligned to frame the sun at sunrise on the June solstice and sunset on the December solstice.

Orbital Plane

The path or flat surface along which Earth revolves around the sun.

Seasons

The yearly pattern of changes in temperature, length of daytime, and location of sunrise and sunset caused by Earth's tilt.

Northern Hemisphere Winter Sunrise

During this season, the sun rises toward the southeast rather than exactly in the east.

Northern Hemisphere Summer Sunrise

During this season, the sun rises toward the northeast rather than exactly in the east.

Polar Regions (Poles)

Locations that tend to be very cold in winter and stay somewhat cool in summer due to the angle of sunlight.

Equator Climate

The region at sea level that remains warm throughout the year because sunlight hits nearly perpendicularly.

North Pole Orientation

A point that appears to point to the same place in space throughout the year as Earth revolves.

Angle of Sunlight Concentration

The factor that determines how much a spot on Earth is heated and why poles are colder than the equator.

Daytime Length Cause

A pattern caused by the tilt of Earth's axis relative to the sun as it travels its orbit.

Solargraph Exposure Time

The total duration that a pinhole camera records sunlight, which can range from days to months, affecting the number of sun tracks captured.

Pinhole Camera Orientation

The direction in which a pinhole camera is pointed, significant for determining the sun's path captured in a solargraph.

Light-Sensitive Surface

The treated paper inside a pinhole camera that changes color when exposed to light, forming the base of a solargraph.

Sun Path Variation

The changing trajectory of the sun across the sky throughout the year, which impacts the length and arcs of sun tracks in solargraphs.

Latitude Effects on Sun Tracks

The geographical coordinate determining how high or low the sun's path appears in solargraphs; lower latitudes see higher arcs.

Project Contributions

Public participation encouraged by Tarja Trygg through a website, allowing individuals to submit solargraphs from various locations.

Photo Inversion Process

The process of using photo-editing software to invert the colors of scanned images, transforming negatives into positives.

Secure Camera Placement

The practice of firmly positioning a pinhole camera to avoid movement, ensuring consistent exposure of the sky over time.

Artistic Interpretation

The creative aspect of solargraphs, which reflect personal and environmental connections through varying light patterns and locations.

Long-Term Exposure Photographs

Photographic techniques that capture gradual changes over extended periods, exemplified by solargraphs through pinhole cameras.

Tarja Trygg Project

An art project where Finnish artist Tarja Trygg collected solargraphs from around the world and displayed them publicly.

Solargraph Elements

Key components of a solargraph include the location, exposure time, camera direction, and the time of year when the photograph was taken.

Environmental Impact on Solargraphs

Different weather conditions and seasonal changes impact the quality and characteristics of solargraphs taken in various locations.

Building a Pinhole Camera

The process of constructing a pinhole camera using a clean beverage can, black cardstock, and duct tape to create a light-tight structure.

Securing the Camera

Ensuring that the pinhole camera is attached to a stable surface for consistent exposure over time without movement.

Removal of Shutter

The action of taking off the piece of tape covering the pinhole to begin the exposure process for capturing the sun's path.

Impact of Latitude

The latitude of a location affects the sun's path; higher latitudes experience lower sun arcs, while those near the equator see higher paths.

Scanning Solargraphs

The process of digitizing the photographic paper to create a digital negative of the solargraph image for further processing.

Inversion Technique

The method used in photo editing to convert a negative image into a positive one, revealing the distinct sun tracks in a solargraph.

No Peking Rule

The practice of not looking at the pinhole camera during its exposure time, emphasizing patience to achieve the final solargraph image.