Astronomical Society of Victoria

25/06/2026

𝐖𝐨𝐫𝐥𝐝'𝐬 𝐎𝐥𝐝𝐞𝐬𝐭 𝐊𝐧𝐨𝐰𝐧 𝐀𝐬𝐭𝐞𝐫𝐨𝐢𝐝 𝐂𝐫𝐚𝐭𝐞𝐫 𝐈𝐬 𝟑 𝐁𝐢𝐥𝐥𝐢𝐨𝐧 𝐘𝐞𝐚𝐫𝐬 𝐎𝐥𝐝, 𝐒𝐭𝐮𝐝𝐲 𝐂𝐨𝐧𝐟𝐢𝐫𝐦𝐬.
When scientists disagree, sometimes the truth is somewhere in the middle.

That has turned out to be true for the age of an impact crater deep in the remote scrublands of Western Australia's Pilbara desert.

Initially, the team that discovered the North Pole Dome impact structure (aka Miralga) estimated its age at about 3.47 billion years – far older than any other impact evidence discovered to date.

But then a second team challenged that estimate, arguing that the crater must be less than 2.77 billion years old.

Now, the original team has studied tiny crystals in the site's impact structures, and determined that the event that created the crater took place around 3.024 billion years ago – confirming its status as the oldest impact crater known on Earth.

When scientists disagree, sometimes the truth is somewhere in the middle.

24/06/2026

What a wonderful evening at Grazing and Gazing!

The Astronomical Society of Victoria was delighted to partner with Balgownie Estate for an evening that brought together exceptional food, great company, and the beauty of the night sky last Saturday night.

Guests enjoyed a themed three course meal specially created for the event while our volunteers guided them through the winter night sky, showcasing some of the fascinating objects visible in our winter skies, sharing stunning astronomical images captured by our members, and demonstrating how to get started with astronomy using a telescope. We also had plenty of fun playing Space Movie Bingo, with the lucky winners taking home bottles of wine and a free ASV membership.

A big thank you to the wonderful team at Balgownie Estate for helping create such a memorable evening, and to our volunteers for sharing their time, knowledge, and passion for astronomy with the guests.

We are already looking forward to the next Grazing and Gazing event on 7 November and hope to see many of you there!

24/06/2026

𝐓𝐡𝐞 𝐂𝐡𝐞𝐦𝐢𝐬𝐭𝐫𝐲 𝐨𝐟 𝐈𝐧𝐭𝐞𝐫𝐬𝐭𝐞𝐥𝐥𝐚𝐫 𝐂𝐨𝐦𝐞𝐭 𝟑𝐈/𝐀𝐓𝐋𝐀𝐒 𝐈𝐬 𝐔𝐧𝐥𝐢𝐤𝐞 𝐀𝐧𝐲𝐭𝐡𝐢𝐧𝐠 𝐖𝐞'𝐯𝐞 𝐄𝐯𝐞𝐫 𝐒𝐞𝐞𝐧.
All signs were already indicating that interstellar comet 3I/ATLAS was unlike anything we'd ever seen.

When it zoomed through the inner Solar System last year, the swarm of telescopes that homed in on it revealed that not only was it without peer in the Solar System, but that it was also dramatically different from either of the two previous known interstellar objects, 1I/'Oumuamua and 2I/Borisov.

Now, a deep analysis of some of the highest-fidelity observations hints that this strange comet may be nearly as old as the Universe itself.

By studying ratios of hydrogen and carbon isotopes, a team led by molecular astrophysicist Martin Cordiner of NASA Goddard Space Flight Center has discovered that the comet formed somewhere very cold, and very primordial – and may be as old as 12 billion years.

All signs were already indicating that interstellar comet 3I/ATLAS was unlike anything we'd ever seen.

23/06/2026

𝐈𝐭'𝐬 𝐎𝐟𝐟𝐢𝐜𝐢𝐚𝐥: 𝐓𝐡𝐢𝐫𝐝 𝐆𝐚𝐥𝐚𝐱𝐲 𝐅𝐨𝐮𝐧𝐝 𝐖𝐢𝐭𝐡 𝐍𝐨 𝐃𝐚𝐫𝐤 𝐌𝐚𝐭𝐭𝐞𝐫 𝐌𝐚𝐲 𝐒𝐨𝐥𝐯𝐞 𝐚𝐧 𝐄𝐩𝐢𝐜 𝐌𝐲𝐬𝐭𝐞𝐫𝐲.
Most of the mass in galaxies consists of stuff we cannot see.

According to current galaxy formation models, galaxies form inside massive blobs of dark matter that act as gravitational scaffolding, helping pull ordinary matter together.

Which makes a discovery about a galaxy 67 million light-years away both perplexing and tremendously exciting.

Its name is NGC 1052-DF9, and it's neither the first, nor the second, but the third galaxy yet whose motions can be explained without dark matter.

And the first two galaxies – known as DF2 and DF4 – belong to the same trail of galaxies wherein DF9 resides, lined up close together like diamonds on a chain.

Although we don't yet know how these galaxies ended up without dark matter, astronomers had previously predicted that if this trail had formed in an unusual way, other galaxies along it might also be missing dark matter.

DF9 appears to fit that prediction.

Most of the mass in galaxies consists of stuff we cannot see.

21/06/2026

May your week be filled with clear skies and bright stars.

21/06/2026

𝐒𝐜𝐢𝐞𝐧𝐭𝐢𝐬𝐭𝐬 𝐂𝐫𝐚𝐜𝐤𝐞𝐝 𝐎𝐩𝐞𝐧 𝐚 𝐌𝐚𝐫𝐬 𝐌𝐞𝐭𝐞𝐨𝐫𝐢𝐭𝐞 𝐀𝐧𝐝 𝐅𝐨𝐮𝐧𝐝 𝐚 𝐁𝐢𝐠 𝐒𝐮𝐫𝐩𝐫𝐢𝐬𝐞.
Cracking open a meteorite that landed on Earth from Mars has yielded an unexpected treasure.

Hidden inside a fragment of rock, scientists found a few grains of garnet – a mineral that has never before been found in a Martian sample.

This tiny speck raises some enormous questions.

On Earth, garnet often forms under conditions involving intense heat, pressure, or chemical alteration. The right set of conditions for garnet has never been identified on Mars.

Cracking open a meteorite that landed on Earth from Mars has yielded an unexpected treasure.

20/06/2026

𝐖𝐢𝐧𝐭𝐞𝐫 𝐒𝐨𝐥𝐬𝐭𝐢𝐜𝐞.
Today marks the Winter Solstice in Melbourne, the shortest day and longest night of the year.

As Earth continues its annual journey around the Sun, our nearest star reaches its lowest midday position in the sky. At noon, the Sun climbs to only 28.5° above the northern horizon, casting the longest shadows of the year.

The word solstice comes from the Latin words sol (Sun) and sistere (to stand still), because the Sun appears to pause in its northward and southward movement before slowly reversing direction.

From tomorrow onward, daylight will gradually increase as we begin the long journey back toward spring and summer. Take a moment today to enjoy the beauty of the winter sky, the crisp air, and the wonder of the seasons that connect us to the movements of our planet and the Sun.

20/06/2026

𝐌𝐨𝐨𝐧 𝐈𝐦𝐩𝐚𝐜𝐭 𝟑.𝟓 𝐁𝐢𝐥𝐥𝐢𝐨𝐧 𝐘𝐞𝐚𝐫𝐬 𝐀𝐠𝐨 𝐇𝐢𝐧𝐭𝐬 𝐚𝐭 𝐇𝐢𝐝𝐝𝐞𝐧 𝐄𝐫𝐚 𝐨𝐟 𝐒𝐨𝐥𝐚𝐫 𝐒𝐲𝐬𝐭𝐞𝐦.
Tiny crystal grains trapped inside a meteorite may be the key that unlocks a hidden era in the Solar System's history of violence.

These particles are so small they can barely be seen without the aid of a microscope, yet they were forged in an asteroid impact that struck the Moon 3.5 billion years ago, according to a team led by planetary scientist Carolyn Crow of the University of Colorado Boulder.

Exactly where this impact took place is unknown, but the grains – a zirconium-rich mineral called baddeleyite – could only have been forged under extreme heat, suggesting the impact was a monumental one.

And there's something else this phantom impact may be telling us.

Evidence from at least two other Solar System bodies – Earth and the asteroid Vesta – preserves the scars of heavy impacts from around the same time period, suggesting that 3.5 billion years ago, the inner Solar System was still playing asteroid pinball, long after it was thought to have calmed down.

Tiny crystal grains trapped inside a meteorite may be the key that unlocks a hidden era in the Solar System's history of violence.

19/06/2026

𝐍𝐀𝐒𝐀’𝐬 𝐂𝐡𝐚𝐧𝐝𝐫𝐚 𝐅𝐢𝐧𝐝𝐬 𝐔𝐧𝐞𝐱𝐩𝐞𝐜𝐭𝐞𝐝 𝐅𝐢𝐫𝐞𝐰𝐨𝐫𝐤𝐬 𝐢𝐧 𝐀𝐟𝐭𝐞𝐫𝐦𝐚𝐭𝐡 𝐨𝐟 𝐒𝐭𝐞𝐥𝐥𝐚𝐫 𝐄𝐱𝐩𝐥𝐨𝐬𝐢𝐨𝐧𝐬.
The aftermath of a supernova, a stellar explosion, is usually a slowly fading cloud of hot gas. So when astronomers pointed NASA's Chandra X-ray Observatory at the nearby galaxy Messier 83 (M83), they did not expect to find a population of supernova remnants, or the debris from these explosions, showing dramatic changes in their brightness. The new results were presented at the American Astronomical Society meeting in Pasadena, California, and published in The Astrophysical Journal.

The galaxy M83, located about 15 million light-years from Earth, is forming stars at a high rate. Researchers analyzed 14 years of Chandra data of the galaxy, spanning 2000 to 2014.

Using this extensive set of data, the researchers caught surprising variations in the X-ray brightness of sources previously identified as supernova remnants. The researchers expected supernova remnants older than a century or so to fade gradually in X-rays, but not change dramatically in brightness.

The team found that roughly half of the 22 X-ray sources associated with supernova remnants in their sample showed changes in X-ray brightness over the 14-year span of observations — a result that was completely unexpected.

Over a 14-year period from 2000 to 2014, astronomers pointed NASA’s X-ray observatory at the M83 galaxy. They discovered that about half of the X-ray sources

17/06/2026

Join Sue from DWARFLAB for an online AstroTalk exploring how compact smart telescopes can make astronomy more accessible for beginners, schools, outreach programs, and public observing events. The session will introduce DWARF 3 and DWARF mini use cases, including deep-sky imaging, lunar and solar observing, beginner-friendly astrophotography, and practical ways smart telescopes can support community engagement.

There will also be time for questions and discussion.

When: Wednesday June 17th from 8:00pm
Where: ONLINE ONLY VIA YOUTUBE/FACEBOOK/TWITCH