SkyEye

The Calendar

The Solar System

The word planet is derived from the Greek word for 'wanderer'. Unlike the background stars, planets seem to move around the sky, keeping mostly to a narrow track called the ecliptic, the path of the Sun across the stars. Dwarf planets and small solar-system bodies, including comets, are not so constrained, often moving far above or below the ecliptic.

Sun Leo → Virgo

The solar north pole is most inclined toward the Earth early this month.

Mercury Virgo → Leo

This tiny planet still shows up in the west after sunset for southern hemisphere observers but soon vanishes to undergo inferior conjunction on 12 September. Mercury reappears in the east before sunrise late in the month when it is best seen from northern latitudes. It attains greatest elongation west on 28 September and is occulted by the Moon the following day.

Venus Virgo

The evening star stays close to the western horizon as seen from the northern hemisphere but for southern observers, Venus gets appreciably higher in the sky as the month progresses. The Moon occults Venus during the daytime on the third day of the month.

Mars Scorpius → Ophiuchus → Sagittarius

The red planet reaches east quadrature on 13 September and sets mid-evening after Saturn.

Jupiter Virgo

At solar conjunction on 26 September, the largest planet in the solar system is lost in the Sun's glare this month. It is occulted by the Moon twice, on the second and on the last day of the month but cannot be observed in either instance. Jupiter reappears in the morning sky next month.

Saturn Ophiuchus

At east quadrature on 2 September, the interplay of shadows — disc, rings, satellites — in the Saturnian system are at their most pronounced. Saturn sets ever earlier in the evening.

Uranus Pisces

Uranus rises in mid-evening and is getting ever brighter as it approaches opposition next month.

Neptune Aquarius

A small telescope is necessary to view the most distant planet in the solar system. Opposition is on the second day of the month so this blue ice giant is aloft most of the night. Parts of Europe and Russia may see this planet occulted by the Moon on 15 September.