Celestial gathering in Sagittarius

FOR me, one of the greatest pleasures of stargazing is using a telescope to survey our solar system.

Even small telescopes reveal extraordinary vistas; I certainly never tire of exploring the lunar terminator (the zone between dark and light on the moon) and watching the shadows created as the sun rises and sets over myriad craters and mountains.

The planets are also a constant source of wonder. Who can forget their first telescopic view of Saturn’s glorious rings, or the extraordinary complex beauty of Jupiter’s clouds.

Luckily, the next few months are a very good time to gaze upon the planets. That’s because, in addition to the moon, Mars, Jupiter and Saturn will all be bright and easy to spot.

Mars is of particular interest this year, since in July, when the planet will be high in the sky at midnight, the red planet will be closer to Earth than at any time since 2003.

Next weekend, Otago skywatchers have a chance to preview the wonders of the next few months, when the moon, Saturn and Mars gather in Sagittarius to form an intriguing spectacle in the earlymorning sky.

Moonrise occurs just before midnight on Saturday, and by dawn, our closest celestial neighbour will stand high in the northern sky. The moon (which reaches lastquarter phase on Sunday evening) will certainly be worthy of close examination, with the Apennine Mountain Range sweeping dramatically towards the lunar terminator.

On Sunday, Mars and Saturn will be within five degrees of the moon (that’s less than the angle subtended by three middle fingers held at arm’s length). Mars will be the brighter of the two planets, and will, of course, appear to be a red/orange hue in contrast to the yellow white of Saturn. Through a telescope, Mars’ tiny disc resembles a gibbous moon. That’s because the relative positions of Earth, Sun and Mars mean that, from our viewpoint, only 87% of the planet is illuminated.

Telescopically, Saturn will be stunning; this year gives us one of the best views of its ring system, which is favourably tilted towards Earth.