Skynotes: October 2025
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A Century of Planetariums
It’s been a remarkable journey from 1925 to 2025 bringing the stars indoors for all to enjoy. Learn the story of technical innovation and creativity in this article from The Conversation, For 100 years, we have marvelled at planetariums.
Interior of Melbourne’s first ‘night sky theatre’, the H.V. McKay Planetarium located on Swanston St in the heart of Melbourne in the then Science Museum (formerly the Institute of Applied Science), a building now fully occupied by the State Library. A popular attraction for the public and schools, the planetarium operated from 1965 until 1997. This 1970s photo shows circular seating for around 110, the central Japanese GOTO M-1 optical star projector, and the 10-metre fibreglass dome with mock city skyline. Seasonal and specially themed shows were all live, and included images from mechanical slide projectors and special effects projectors, sound effects, music, and commentary by the presenter.
December Skynotes will feature more about Melbourne's first planetarium as we mark the 60th anniversary of its opening in December 1965.
Melbourne Sun times
| Date | Rise | Set | Day length | Solar noon* |
|---|---|---|---|---|
| Wednesday 1st | 5:55am | 6:24pm | 12:28hours | 12:09pm |
| Saturday 11th | 6:40am | 7:33pm | 12:52hours | 1:06pm |
| Monday 21st | 6:26am | 7:43pm | 13:16hours | 1:04pm |
| Friday 31st | 6:14am | 7:53pm | 13:39hours | 1:03pm |
*When the sun is at its highest, crossing the meridian or local longitude.
Australian Eastern Daylight Time (AEDT) begins on Sunday 5th at 2am when clocks move forward 1 hour.
Moon phases
| Phase | Date |
|---|---|
| Full Moon | Monday 7th |
| Third Quarter | Tuesday 14th |
| New Moon | Tuesday 21st |
| First Quarter | Thursday 30th |
Moon distances
Lunar apogee (furthest from Earth) is on Friday 24th at 406,444 km.
Lunar perigee (closest to Earth) is on Tuesday 8th at 359,819 km.
Planets
Mercury after its solar conjunction, is now visible again in the west from 8pm before setting around 9pm.
Venus has drawn too close to the Sun this month for observers in Melbourne.
Mars is about to have its solar conjunction and pass behind the Sun but can still be seen this month low in the west at twilight from around 8:15pm before setting by 9:30pm.
Jupiter is now visible again from 3am in the east before fading in the dawn light by 6:30am.
Saturn can now be seen again in the east at dusk from 8pm, after which it will move across the northern sky before setting in the west by 5am.
Meteors
The Orionids appear from the 15th-29th but peak on the 21st-22nd with perhaps 30 meteors per hour from midnight until dawn. Centred on Orion near the red supergiant star Betelgeuse, they are typically very fast and bright entering the atmosphere at 66 km per second and vaporising 100 km above the surface leaving persistent trails. Dr Tanya Hill and Professor Jonti Horner explain the meteor shower in The Conversation.
The Orionids shower was first recorded by the Chinese in 288 AD and is associated with Comet Halley. In 1705, Edmund Halley, after studying records of comets that seemed to re-occur and using Isaac Newton’s new laws of motion, calculated the comet’s orbit and predicted its return in 1758 (something he did not live to see). Every 75 years Comet Halley passes through the inner solar system leaving a trail of particles for Earth to pass through twice a year - the April/May Eta Aquarids and the October Orionids.
Stars and constellations
In the north
Visible this season are Aquila (the Eagle) and its principal star Altair (Alpha Aquilae) directly north.
In the west
Scorpius is now moving down to the west with the red-giant star Antares the middle of three stars that mark the scorpion’s body. High above following the scorpion is the asterism ‘the teapot’ which gives you the position of the bow and arrow held by the centaur Sagittarius. The centre of our Milky Way galaxy lies in that direction some 26,000 light years away.
In the east
Formalhaut in Piscis Austrinus (Southern Fish) is the bright evening star in the east this month. But as spring ends and we move towards summer we will progressively begin to see from the north-east to the south-east a rich collection of night sky objects:
- The beautiful Pleiades cluster (the Seven Sisters).
- Taurus the bull with red giant star
- The inverted Orion the hunter (with the right way up ‘Saucepan’ at its centre), and red supergiant
- Canis Major and the brightest night time star Sirius (also known as The Dog Star).
In the south
In a dark sky in the south-east are the isolated Large and Small Clouds of Magellan (our galaxy’s nearest neighbours) as well as the vast band of billions of stars and dark dust clouds that make up what we can see of our own galaxy, the Milky Way. In the evenings this month it runs in a broad arc from south to north. From our location in our disc-shaped galaxy we have an edge-on view along the plane of the galaxy where the density of stars is greatest. As you look away from the Milky Way to either side of the sky you see far fewer stars because in those directions you are looking through only a few thousand light years out into intergalactic space, to the north or to the south of the galactic plane.
Low in the south-west are the Pointers, Alpha and Beta Centauri, in the constellation of Centaurus (the other centaur in our night skies). Following the line of the two bright Pointers leads to the Crux (Southern Cross).
International Space Station
At a distance of about 400km the ISS completes an orbit every 90 minutes and appears as a bright point slowly moving across the night sky. Here are some of the brightest passes expected this month over Melbourne:
Morning
Saturday 4th 5:17am-5:23am South-West to East-North-East
Tuesday 7th 5:27am-5:32am South-West to North-East
Evening
Saturday 11th 8:25pm-8:32pm North-West to South-East
Tuesday 28th 8:52pm-8:57pm South-West to North-East
Heavens Above gives predictions for visible passes of space stations and major satellites, live sky views and 3D visualisations. Be sure to first enter your location under ‘Configuration’.
On this day
3rd 1942, first object to reach space, the experimental V2 (‘Vengeance’) rocket, was launched from Peenemünde, Germany in a brief flight over the Baltic.
4th 1957, Sputnik (USSR) was launched to become the first artificial satellite.
4th 2004, SpaceShipOne was launched as the first private spacecraft into space.
5th 1923, Edwin Hubble (USA) established that M31, the Andromeda Galaxy, is separate to our own Milky Way Galaxy.
7th 1959, first photos of the moon’s far side are taken by Luna 3 (USSR).
9th 1604, a Type1A supernova 20,000 light years away in constellation Ophiucus is visible from Earth, and on 17th Johannes Kepler observes and publishes his account of the new star. It is the most recent supernova visible to the naked eye in our galaxy.
10th 1967, the United Nations’ Outer Space Treaty on the peaceful exploration and use of space was established. By now 109 nations are signatories and several other agreements and conventions have been created to cover space law.
11th 1958, Pioneer 1 (USA), a battery- powered probe aiming for lunar orbit, fails to reach escape velocity and burns up.
11th 1968, first crewed Apollo mission, Apollo 7 (USA), launched into Earth orbit in test of Saturn V rocket and Command and Service Module (CSM).
12th 1964, USSR’s Voskhod 1 (‘Sunrise’) was the first spacecraft with a crew of more than one. In this case, three cosmonauts who orbited for 41 hours.
13th 1773, the Whirlpool Galaxy M51a, 31 million light years away in constellation of Canes Venatica, is discovered by astronomer Charles Messier.
18th 1967, Venera 4 (USSR) is the first probe to analyse the atmosphere of another planet when it does so at Venus.
19th 1910, birth of Subrahmanyan Chandrasekhar who had major insights into stellar evolution and black holes.
24th 1998, Deep Space 1 (USA) probe was launched to test innovative technologies, including an ion engine, while visiting Asteroid Braille and Comet Borrelly.
27th 1994, first sub-stellar object orbiting a star is found, a brown dwarf at Gliese 229.
29th 1991, Galileo probe (USA) is the first to visit an asteroid, Gaspra 951, on its way to Jupiter.
31st 2000, Expedition 1, first resident crew of the International Space Station, arrived by a Russian Soyuz craft for a 136 day stay lasting until March 2001. The three-person crew (one American and two Russians) made the station fully operational, hosted three visiting US Space Shuttles, and received two Russian Progress supply vehicles.
