Skynotes Junes 2009

MONTH HIGHLIGHTS

Winter is here, so it's time to rug up and take advantage of the crisp, dark evenings to do some stargazing. Saturn is the only planet visible after sunset and it is shining brightly in the northern sky. However, at this time of year it's best to look towards the south. There the Southern Cross sits high in the sky and if you are away from city lights, you'll find the glorious Milky Way stretching across the sky.

In the early hours of the morning there are many planets to be found. Jupiter sits high in the north-west, Venus and Mars are together in the north-east and Mercury is low to the eastern horizon.

WINTER SCHOOL HOLIDAYS

Scienceworks is opened daily from 10am – 4:30pm. During the school holidays (27th June – 12th July) planetarium session times are:

11am & 1pm: Tycho to the Moon

12pm, 2pm & 3pm: Search for Life: Are we alone?

See the Melbourne Planetarium's What's On listing for more details.

SUNRISE & SUNSET TIMES

MOON PHASES

The Moon will be at perigee (closest to Earth) on Sunday 23rd, at a distance of
358 017 km.

The Moon will be at apogee (furthest from Earth) on Thursday 11th, at a distance of 405 785 km.

LET THE MOON BE YOUR GUIDE

The Moon can be used as a pointer to find other objects in the sky.

• After sunset on the 1st the waxing gibbous Moon sits above Saturn.
• On the 3rd the Moon is near Spica, the brightest star in the constellation Virgo.
• After sunset on the 7th the Full Moon rises in the east, sitting just below the red supergiant star Antares (Scorpius).
• On the night of the 13th the waning gibbous Moon rises around 10pm near Jupiter.
• During the early hours of the 19th the waning crescent Moon sits to the left of Venus and Mars.
• Low to the north-east horizon on the morning of the 21st, the crescent Moon can be found below the star cluster Pleiades and to the left of Mercury.
• During the early evening of the 28th the waxing crescent Moon sits above Saturn.
• On the 30th the Moon is close to Spica (Virgo).

PLANETS

Mercury appears in the early morning sky, towards the eastern horizon. By the end of the month Mercury sits near the triangle of stars that marks Taurus, the bull. On the morning of the 21st the thin crescent Moon lies to the left of Mercury and the red giant star Aldebaran lies to the right.

Venus is now the morning star, shining brightly in the north-east. It starts the month sitting above Mars but by the 26th it sits directly to the right of the red planet. The crescent Moon sits to the left of Venus and Mars on the 19th.

Earth experiences the Winter Solstice at 3:45pm on Sunday 21st. This is the moment when the Sun reaches its northern-most point in the sky. It also brings about the shortest day of the year, when here in Melbourne we have just 9 hours and 32 minutes of daylight.

Mars can be found in the morning sky with bright Venus.

Jupiter is high in the north-west at sunrise. It sits to the right of the Moon on the morning of the 13th.

Saturn is the only planet visible at sunset. It lies towards the north and is the brightest object in that part of the sky. To the left of Saturn is the constellation of Leo, the lion which includes the bright star Regulus. The Moon sits above Saturn on the 1st and then again on the 28th.

METEORS

There are a number of meteor showers occurring in Scorpius and Sagittarius this month. Although low in number (less than 10 per hour) the shower members can often be spectacular, appearing slow and bright with many displaying a yellow/orange colour. The best time to see meteors is after midnight.

STARS & CONSTELLATIONS

Low in the west we have our last look at the brightest star in the night sky, Sirius, before the constellation of Canis Major (the great dog) disappears from our sky for the winter. Above and to the south of Sirius is the second brightest star in the night sky, Canopus in Carina (the keel). Looking further south and low to the horizon you may be able to identify the bright star Achernar in Eridanus (the river) at its lowest point in the sky. Directly above Achernar, the Southern Cross reaches its highest point and remains there majestically during the winter months.

Looking eastward, the bright red star Antares, in the constellation of Scorpius (the scorpion), can be seen. Below it lies the teapot shape of Sagittarius (the archer). The region around Sagittarius is a rich area of the sky to explore with binoculars. It points towards the centre of our Milky Way Galaxy, which lies 26 000 light years away and contains a supermassive black hole.

INTERNATIONAL SPACE STATION

From Earth, the ISS appears as a bright star that steadily moves across the sky. It can often be seen from Melbourne, for example at:

6:24pm – 6:28pm, Sunday 14th June.

The Station will first appear above the north-west horizon and travel past Saturn before disappearing in the east.

Predictions of when to see the ISS can be obtained from the Heaven's Above website.

ON THIS DAY

1st 2002, the Czech Republic becomes the first country to ban light pollution.

6th 1799, the first standard metre and kilogram of the metric system are made in France.

6th 1971, Soyuz 11 (USSR) was launched. It carried the first people to a space station (Soviet Salyut 1).

11th 1985, a balloon (from Vega 1, USSR) is used to explore another planet, Venus.

14th 1965, Mariner 4 (USA) returns the first close-up images of Mars.

15th 1999, a near-miss for the International Space Station as space debris passes just 7 km from the station.

16th 1963, Valentina V. Tereshkova (USSR) launched on Vostok 6 becomes the first woman in space.

18th 1983, Sally Ride is the first US woman in space (on the space shuttle Challenger).

20th 1939, Germany launches the first liquid-fuel rocket plane.

22nd 1978, Dr James W. Christy (USA) discovers Pluto’s satellite Charon.

23rd 1971, the Soyuz 11 (USSR) three-man crew die upon re-entry to Earth.

30th 1908, a meteor explodes over Tunguska, Russia, destroying 2,200 km² of forest.