Project #190 on iSENSEProject.org
Data from timeanddate.com on sunrise and sunset times.
The times for sunrise and sunset are based on the ideal situation, where no hills or mountains obscure the view and the flat horizon is at the same altitude as the observer. Sunrise is the time when the upper part of the Sun is visible, and sunset is when the last part of the Sun is about to disappear below the horizon (in clear weather conditions).
If the horizon in the direction of sunrise or sunset is at a higher altitude than that of the observer, the sunrise will be later and sunset earlier than listed (and the reverse: on a high mountain with the horizon below the observer, the sunrise will be earlier and sunset later than listed).
The Earth's atmosphere refracts the incoming light in such a way that the Sun is visible longer than it would be without an atmosphere. The refraction depends on the atmospheric pressure and temperature. These calculations use the standard atmospheric pressure of 101.325 kilopascal and temperature of 15°C or 59°F. A higher atmospheric pressure or lower temperature than the standard means more refraction, and the sunrise will be earlier and sunset later. In most cases, however, this would affect the rising and setting times by less than a minute. Near the North and South Poles it could have greater impact because of low temperatures and the slow rate of the Sun's rising and setting.
Name | Units | Type of Data |
---|---|---|
Time
|
None
|
Timestamp
|
Sunrise
|
Time of Day
|
Number
|
Sunset
|
Time of Day
|
Number
|
Day Length
|
Hours
|
Number
|
Solar Noon
|
Time of Day
|
Number
|
Altitude
|
Degrees
|
Number
|
Distance
|
Million Miles
|
Number
|
Time | Sunrise | Sunset | Day Length | Solar Noon | Altitude | Distance |