SkyEye

The Calendar

The Moon reaches both its nearest apogee and farthest perigee of the year this month whilst Earth arrives at an equinox, marking a change in astronomical seasons.

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 Aquarius → Pisces

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

Mercury Capricornus → Aquarius → Pisces → Cetus

Mercury is heading back toward the eastern horizon but is still well-placed for observation at the beginning of the month for early risers in the southern hemisphere. It has three close encounters with gas giants this month, Saturn on the second day of the month, Jupiter on 21 March and Neptune two days later. The latter two planetary conjunctions will be particularly difficult as Mercury will be deep in the brightening sky by then.

Venus Sagittarius → Capricornus → Aquarius → Capricornus

Venus and Mars meet again this month, on 6 March, when the two bodies are 4.5° apart in the sky. The morning star has a much closer visit with Saturn near the end of the month, on 28 March. Before this encounter with the ringed planet, however, Venus attains its greatest elongation west of 46.6° on 20 March. The morning star is high in the sky for southern hemisphere observers but remains very low to the horizon for astronomers in northern temperate latitudes.

Earth and Moon

Earth reaches the first of two equinoxes on 20 March. The word equinox means 'equal night' so that on this day, the (centre of the) Sun spends an equal amount of time above and below the horizon everywhere on the planet. Like last month, the waxing crescent Moon occults Uranus on the seventh day. The Moon also undergoes the nearest apogee (10 March) and farthest perigee (23 March) of the year.

Mars Sagittarius → Capricornus

Mars has another encounter with Venus this month when the red planet appears 4.5° south of the morning star. The first-magnitude object outshines the much dimmer ι Capricorni when it comes to within 0.2° of the fourth-magnitude variable star on the penultimate day of the month. To witness any of these events requires an early start; Mars is only visible during the hours right before and during dawn and is best viewed from the southern hemisphere.

Jupiter Aquarius

Jupiter is at conjunction early this month and is lost in the glare of the Sun. It reappears in the morning sky late in March. Southern hemisphere observers may see Mercury pass the gas giant on 21 March but Jupiter's incredibly close pass by fourth-magnitude star φ Aquarii six days earlier is probably lost in the dawn sky.

Saturn Capricornus

Saturn remains hidden in dawn skies for early risers in northern temperate latitudes but rises well ahead of the Sun as seen from the southern hemisphere. It is south of the equator that planet watchers will have the best opportunities to spot Mercury and Saturn close together on 2 March and then the morning star nearby on 28 March.

Uranus Aries

Like last month, the waxing crescent Moon occults Uranus, this event being visible from New Zealand and some of the islands of Melanesia and Polynesia from 07:00 UT. The faint planet is setting ever earlier but is still above the horizon in the early evening after the sky gets dark.

Neptune Aquarius

Neptune is at conjunction this month and is lost in the glare of the Sun.