Day of yearJune 21

Latitude40.7° N

Time of day12:00

Jump to a date

Jump to a place

Day of year

Latitude (south is negative)

Time of day (solar hours)

Play speed

Presets

Axial tilt

Orbit eccentricity (0 is a circle)

Date of closest approach to the Sun

Earth's real tilt is 23.5 degrees and its real eccentricity is 0.0167. Moving the date of closest approach shifts it relative to the seasons, as the slow wobble of Earth's axis does over about 26,000 years.

Zoom (times)

View angle (up and down)

View turn (around)

Scroll or pinch to zoom, drag to turn the view, double-click to focus on Earth, R resets.

Sunrise and sunset use the standard 0.83 degree allowance for air bending the light and the Sun's width. Times are local solar time, so noon is when the Sun is highest.

Stick height

Sun height set by hand

Compare with latitude

The readout row sits on the stage. In presentation mode it also shows the Sun's height, bearing, shadow, sunrise and sunset.

Hides the panel, enlarges the labels and readouts and gives the stage the whole screen. Press P or Esc to come back.

Text size

Label size (percent)

Appearance

Animation

Graphics quality

Ultra draws at a higher pixel density with finer detail. Use it on a projector with a capable computer. Auto adapts to keep motion smooth.

Keys: Space plays or pauses, left and right arrows change the date (Shift for a week), up and down change latitude, 1 to 6 switch views, P presentation mode, R resets the 3D camera, F focuses on Earth, plus and minus zoom, D switches light and dark, Esc closes this panel. Drag Earth in the Orbit view to set the date.

Sun's path across the sky

Shadow of a stick

Height of the noon Sun

Spread of sunlight

Daylight through the year

Noon Sun height through the year

Sun height through the day