A Digital Orrery

The chart below shows the current positions of the planets around their orbits, as projected onto the ecliptic plane. Each of the planets moves anticlockwise in this projection. Their orbits are labelled with their closest and further points from the Sun – perihelion and aphelion respectively – although only Mercury and Mars vary appreciably in their distance from the Sun. The Earth's orbit is also labelled with the points it passes on the first day of each month and on the solstices and equinoxes. A planet may be readily observed in the night sky if the Earth's sightline to it is at an angle well separated from its sightline to the Sun, but not if the planet lies in a similar direction to the Sun. This figure is also available in pdf format.