West Chicago, IL Sunrise and Sunset Times (2024)

FAQs

How do you solve sunrise and sunset? ›

Sunrise/Sunset Calculations

where the positive number corresponds to sunrise, negative to sunset. Then the UTC time of sunrise (or sunset) in minutes is: sunrise = 720 – 4*(longitude + ha) – eqtime where longitude and hour angle are in degrees and the equation of time is in minutes.

UPDATED: December 20, 2023 at 5:28 p.m. Nine hours, 7 minutes and 44 seconds. The winter solstice, which occurs precisely at 9:27 p.m. Thursday, marks the shortest day of the year and the start of astronomical winter in the Northern Hemisphere. Chicagoans will only experience about nine hours of daylight.

It is actually the motion of Earth spinning that gives us the illusion that everything in the sky is moving around us once a day. Earth rotates in an eastward direction once every 24 hours, producing sunrises and sunsets and the apparent westward movement of the objects across the sky.

The sun is visible to us 2 minutes before the actual sunrise because of atmospheric refraction. When the sun is below the horizon the light travelling from rarer to denser medium bends and reaches our eyes creating an impression that it is above the horizon.

Arguably the single most important weather factor in predicting amazing sunrises and sunsets is the clouds. The type of clouds in the sky, the thickness of the cloud cover, and the height of the clouds all play very important factors in creating a great sunrise or sunset.

The solstice, which comes on December 21 in Chicago, is a time when the natural world is gray and brown. Many trees and plants seem dead, though they are only dormant. Nights are long and cold.

This seemed like a lot of cloudiness and it is, but December is tied with January as months averaging least sunshine (40% of possible). Records dating back to 1893 actually show 30 separate Decembers with 30% or less of possible sunshine.

Frank Wachowski, Chicago's weather historian and keeper of the city's sunshine climatology that dates to 1893, combed through the record books and found a record 12-day sunless streak that spanned from Dec. 29, 1991-Jan. 9, 1992.

… Sun and Moon are in syzygy—i.e., aligned with the Earth. Conjunction is the time during new moon when the Sun and Moon lie on the same side of the Earth. The other syzygy condition, opposition, occurs during full moon when the Sun and Moon are positioned on opposite sides of… Read More.

The non-circularity of the orbit and the tilt of the axis of rotation both contribute to the uneven changes in the times of sunrise and sunset. This means that the Sun does not rise earlier by a fixed number of minutes every morning and set later by the same number of minutes.

What is it called when the Sun rises and sets at the same time? ›

These events are referred to as Equinoxes. The word equinox is derived from two Latin words - aequus (equal) and nox (night).

Lawmakers have enshrined the concept of civil twilight. Such statutes typically use a fixed period after sunset or before sunrise (most commonly 20–30 minutes), rather than how many degrees the Sun is below the horizon.

The time interval between two successive sunrises or sunsets is called a solar day, which is also the time the Earth takes to rotate about its axis so that the Sun appears in the same position in the sky.

The statement that you must use your headlights 30 minutes after sunset and keep them on until 30 minutes before sunrise is generally true. Traffic laws often state that motorists must use their headlights during this period to ensure visibility for safe driving.

Conventionally speaking, sunrise and sunset are defined as the moment when the top of the Sun's disk is on the horizon. If we lived on an airless body, we could calculate when this moment happens with simple geometry and call it a day. But light doesn't travel from our star to our eye in a straight line.

The mean solar time has been 1 Page 2 2 M. Müller fixed in such a way that it does not deviate too much from the apparent solar time. The deviations between apparent solar time and mean solar time are described by the equation of time equation of time = (apparent solar time) − (mean solar time).

S = ST - LONG + 1.0027379 * (LST + ZONE - C). Given the local sidereal time, the right ascension and declination of the sun, and the local latitude, then the local azimuth and elevation of the sun can be determined from spherical trigonometry.