Guides
How the sun moves and how to use that knowledge, explained clearly with diagrams and real numbers.
What is golden hour and blue hour?When the warm light of golden hour and the deep blue of blue hour happen, why they look the way they do, and how long they last where you live.Civil, nautical and astronomical twilight explainedThe three stages of twilight, what you can see in each of them, how long they last at different latitudes, and why summer nights in the north never get fully dark.Why the earliest sunset is not on the shortest dayThe earliest sunset and the latest sunrise do not fall on the winter solstice. The reason is the equation of time, and it is easy to see in real numbers.How sunrise and sunset times are calculatedWhat exactly counts as sunrise, why the calculation uses 0.833° below the horizon, what refraction and elevation do, and how accurate the minutes you see really are.What is solar noon?Solar noon is when the sun reaches its highest point. Here is why that is almost never at 12:00 on your clock, and how to work out when it happens.Solstices and equinoxes explainedWhat the solstices and equinoxes are, why their dates move between years, and what they mean for daylight where you live, with exact dates and times.Azimuth and elevation: how to read the sun’s positionThe two angles that describe where the sun is, how to measure them with simple tools, and what they tell you about shade, light and solar energy.How to find which direction your house facesFour reliable ways to find out which way your house or flat faces, and what each direction means for sunlight in your rooms, garden and balcony.Full sun, part shade, shade: how much sun does your garden get?What full sun, part sun and shade mean in hours, how to measure the sunlight in a garden spot through the year, and how fences, walls and trees change it.Best tilt and orientation for solar panelsThe best tilt and direction for solar panels, how much a less-than-perfect roof really costs you, and when other orientations make sense.How to calculate shadow lengthThe one-line formula for shadow length, worked examples, how to go the other way and find a height or sun angle, and how shadows change through the day and year.Daylight saving time and sunrise and sunsetWhat daylight saving time really changes (and what it does not), when clocks change in Europe and North America, and how it shifts your mornings and evenings.Why days are longer in summer (and what the midnight sun is)How the 23.4° tilt of Earth's axis makes summer days long and winter days short, how much that depends on where you live, and why the poles get months of midnight sun and polar night.Planning sunrise and sunset photos with the sun's directionA practical step-by-step method for planning sunrise and sunset photos: timing, the exact direction of the sun, the horizon, the weather and what to do in each phase of the light.How to read a sun path diagramWhat a sun path diagram shows, how to read directions, heights and times from it, and how to use it for houses, gardens and photos.