Skynotes November 2009

Month Highlights

Not a great month for planet watching, so try further afield! November is the month to try to catch a glimpse of M31, the Andromeda Galaxy. At 2.5 million light years away it is the furthest object that can be seen with the unaided eye. In the middle of the month it can be seen just 10° above the northern horizon around 10pm.

Sunrise & Sunset Times 

Moon Phases

The Moon will be at perigee (closest to Earth) on Saturday 7th at a distance of 368 899 km.
The Moon will be at apogee (furthest from Earth) on Monday 23rd at a distance of 404 734 km.

Let the Moon be Your Guide

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

• After midnight on the night of the 4th, the waning gibbous Moon is near the star cluster Pleaides low on the northern horizon.
• In the early hours of the 6th the Moon is near the bright star Elnath in Taurus, the Bull.
• On the morning of the 8th Moon sits above the twin stars of Gemini, Castor and Pollux.
• Before dawn on the 9th the Moon sits west of Mars, the following morning it is on the east of the red planet.
• On the 11th the waning crescent Moon rises near Regulus (Leo) just before the star disappears at sunrise.
• After sunset on the 23rd and 24th the first quarter Moon is near Jupiter.

Planets

Mercury is too near the Sun to be seen this month.

Venus is still seen in the morning sky although it is rising only 40 minutes before the Sun at the beginning of the month and less by the end.

Mars rises after midnight and can be seen in the sky throughout the early morning hours. On the mornings of the 9th and 10th the Moon is near Mars.

Jupiter is still brilliant in the evening sky although it is continuing to fade and sink lower into the west. By the end of the month it is setting around midnight. The first quarter Moon is in the vicinity of Jupiter on the nights of the 23rd and 24th.

Saturn is rising earlier and earlier and by the end of the month is in the morning sky, for nearly three hours before sunrise.

Meteors

The Taurids are an old meteor stream that is visible throughout spring and peaks during the first week of November. There are two branches to the shower, one appearing near the star cluster Pleiades and the other near the red star Aldebaran.

Each branch has a maximum rate of roughly 10 meteors per hour. They have been described as being bright, slow moving and with the occasional colourful fireball.

The now famous Leonids peak around the 18th. This meteor shower is associated with the comet Tempel-Tuttle that orbits the Sun every 33 years. The comet reached perihelion (closest approach to the Sun) in February 1998, and in the following years the Leonids were a spectacular sight worldwide with thousands of meteors seen per hour. In the years since then the shower settled back to its usual rate of around 15 meteors per hour. However in 2009 astronomers predict the best outburst since 2001, although unfortunately the peak will occur after sunrise from Melbourne.

The best time to look for Leonid meteors is 3–5am on the morning of the 18th, although activity will occur from the 13th to the 20th. The meteors will appear to come from the direction of Leo, the lion, which can be found rising in the north-east.

The Leonids are fast meteors that enter Earth's atmosphere at speeds of over 250,000 km per hour. They leave lots of trains and often contain a large number of very bright meteors, whose trains can last for several minutes.

Stars & Constellations

Scorpius and Sagittarius are low in the south-west after sunset and will gradually disappear into the twilight. They make way for the summer constellations, Taurus, the bull and Orion, the hunter that are rising in the east. The Southern Cross is now upside down with the Pointers to the west (right) and the bright star Canopus to the east (left).

This is a good time of year for viewing the most distant object visible to the unaided eye, the spiral galaxy in Andromeda. From dark country skies the Andromeda Galaxy (or M31) can be found just above the northern horizon, sitting below and to the right of the square of Pegasus.

Iternational Space Station

The ISS orbits the Earth every 90 minutes at an average distance of 400 km. 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 4:37am – 4:43am, Tuesday 17th November.

The Station will first appear above the north-west horizon, travelling towards the Southern Cross and passing right between the Alpha and Beta Centauri, the two pointers before setting over the south-east horizon.

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

On this Day

1st 1977, Chiron, the unusual solar system body with both cometary and asteroidal characteristics, is discovered.

2nd  2000, William Shepard (USA), Sergei Krikalev and Yuri Gidzenko (USSR) become the first residents of the ISS.

3rd  1957, Laika (the dog) became the first animal in space onboard Sputnik 2 (USSR).

7th  1631, A transit of Mercury is observed for the first time by Pierre Gassendi.

11th  1572, Tycho Brahe observes a supernova and shows that it is amongst the stars, proving that the heavens are not unchanging.

12th  1981, Columbia (USA) became the first spacecraft to be flown twice.

13th  1971, Mariner 9 (USA) became the first spacecraft to orbit another planet - Mars.

16th  1974, the first intentional interstellar radio message was sent into space from the Arecibo Observatory towards the M13 star cluster, 25 000 light years away (USA/Puerto Rico).

18th  1989, COBE (USA/ESA) the satellite that discovered the remnants of the 'Big Bang' was launched. 

21st  1783, J. de Rozier (France) made the first manned balloon flight.

26th  1965, France became the third nation to launch a satellite.

27th  1971, Mars 2's probe (USSR) became the first craft to impact Mars.

28th  1967, Jocelyn Bell (UK) discovers the first known pulsar, initially named LGM1 for "little green men".

29th  1961, Enos' became the first chimpanzee in space onboard Mercury 5(USA).

29th  1967, Australia becomes the fourth country to lauch a satellite with WRESAT-1.

30th  1609, Galileo Galilei studies the Moon with a telescope for the first time.

30th 1954, Elizabeth Hodges (USA) is hit by a 5kg meteorite in Alabama, one of the few documented instances of such an incident.