SkyEye

The stars are mansions built by Nature's hand,
And, haply, there the spirits of the blest
Dwell, clothed in radiance, their immortal vest…
— William Wordsworth, "The stars are mansions built by Nature's hand", 1820

In each chart, the zenith (position directly over the observer) is located in the centre of the chart and all of the stars are projected from this point. As a result, objects near zenith are as they appear in the sky but objects nearer to the horizon circle are considerably more distorted. Since it is difficult if not impossible to observe things close to the horizon, it is hoped that this distortion will not cause undue problems.

The online charts are drawn in colour on a dark background. Coloured circles of varying radii are used to represent stars. The larger the circle, the brighter the star. Binary and multiple star systems that appear as a single object to the naked eye are represented by their combined magnitude. The colours represent the spectral types (surface temperatures) of the stars, with blue being the hottest and red the coolest.

A selection of other interesting naked-eye objects are drawn in green. Galaxies are represented by ellipses, nebulae are triangles, open clusters are squares and globular clusters are circles. The green lines represent the outlines of the constellations and the white cross at the centre marks the zenith.

To use the sky chart, turn it around until the direction you are facing is located at the bottom. The usable part of the chart ranges from the lower horizon circle to the zenith.

Star positions (epoch 2000), magnitudes and colours are taken from the Smithsonian Astrophysical Observatory Star Catalog. The limiting stellar magnitude is +4.5 with a few fainter stars to fill out the constellation lines. The limiting magnitude for other objects is approximately +6.0.