Sciences

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Sciences

Natural history - from animals to minerals, fossils to sea slugs. MV's scientists use the state's collections in important research.

Gravity waves, cosmic inflation and the multiverse

Author
by Tanya
Publish date
20 March 2014
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Scientists have been whipping up a frenzy this week, following the announcement of a truly mind-boggling discovery last Monday. Astronomers from the Harvard-Smithsonian Centre for Astrophysics (USA) have captured the signature of gravity waves from the early Universe. Now, just like the Higgs Boson announcement from 2012, this one takes a bit of time to wrap your head around, but the consequences are out of this world.

Gravity waves from after the Big Bang The twisting pattern shown here represents the first direct image of gravity waves from cosmic inflation, in the moments just after the Big Bang.
Source: EPA/Harvard University
 

Firstly, this discovery provides the first evidence for gravity waves, a phenomenon that scientists have been searching for over many decades. Gravity waves are tiny ripples in the fabric of spacetime and they were predicted by Einstein's General Theory of Relativity. This theory has now survived every test that could be thrown at it. Even the bizarre notion of time ticking at different rates, depending on gravity and speed, is put into practical use every time we use a GPS to find where we are.

Finding gravity waves could open up a whole new window on the world around us. We are used to looking at the world using light, which are electromagnetic waves. But gravity waves hold just as great a potential. They could be used to see inside a neutron star, to watch a star collapse within a supernova or to examine two black holes colliding. They could even reveal new physics ideas and make it possible to pick up the vibrations of cosmic strings or determine the number of dimensions of the Universe.

Colliding black holes In this artist's impression, two black holes are entwined in a gravitational tango that will eventually collapse the pair into a single black hole.
Source: NASA
 

Secondly, the discovery provides the best proof of cosmic inflation – the idea that within a fraction of a second after the Big Bang, the Universe went through a period of rapid expansion. Picture a child blowing bubbles, but in this case, the Universe grew from absolutely miniscule to larger than the observable Universe in the blink of an eye.

Only cosmic inflation predicts the rise of gravity waves in the early Universe. And now that the theory has passed this test, other predictions of inflation may well hold true; such as spacetime being infinite and that the multiverse concept is real. We are one step closer to the possibility that there exists an infinite number of Universes, separate to ours, that are continually erupting, just like ours did, out of some sort of ever inflating "sea".

Links:

How the detection was made: First hints of gravitational waves in the Big Bang's afterglow by Krzysztof Bolejko (University of Sydney) and Alan Duffy (University of Melbourne), in The Conversation

Taxidermy conservation workshop

Author
by Kate C
Publish date
18 March 2014
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It’s clear that the old penguin specimen needs a lot of work. Age or accident has detached the bird’s head from its body, and preparator Steven Sparrey is carefully working PVA glue into the break in the neck. This will consolidate the edge and provide a sound surface for reattachment. Eventually, preened feathers will conceal the join and the penguin will be whole again.

Damaged taxidermied penguin Detail of damaged taxidermied penguin specimen.
Source: Museum Victoria
 

We’re at a workshop for people in the business of preserving natural history specimens – collection managers, preparators and conservators – led by visiting UK expert Simon Moore. The museum’s conservation laboratory is busy with people transforming elderly and damaged collection objects into exhibition-ready specimens, using specialist techniques that are very rarely taught in this country.

Taxidermy workshop Taxidermy conservation workshop in the conservation lab at Melbourne Museum.
Source: Museum Victoria
 

Sometimes the damage occurs from wear and tear, especially where specimens have done time in the museum’s interpretive collection. Other times it’s inadequate preparation at time of taxidermy – overstuffed specimens tend to split as the skin shrinks with age. Simon explains, “many of the specimens are decades old, and materials just become more brittle with time. “A small bump when handling can have drastic results on a fragile specimen, and the head is often the first to go.
We turn back to Steven’s penguin. “The skin on birds in particular is very thin and vulnerable to tearing,” says Simon. “In this case, the neck was overstuffed. As the skin dries out and retracts back onto the underlying material, it starts to split.” 

The penguin also needs a wing reattached, so Steven drills a fine hole for a galvanised steel rod to hold the wing on a natural angle. Next to him, Michael Pennell is finishing work on a mounted Regent Bowerbird, freshly reunited with its tail and perch. “He’s a little bit cleaner than he was this morning and I’ve filled a few little holes and splits.”

Man and bird specimen Preparator Michael Pennell working on a Regent Bowerbird mount.
Source: Museum Victoria
 

Elsewhere in the room, people are creating supporting armature for rabbit ears, cleaning feathers and mending tears in batwings with Japanese tissue. This tissue, says conservator Dani Measday, has unusually long fibres and resists tearing. “It means that it’s really strong and you can do all kinds of things with it. We use it to repair paper and books , but you can use it as fill, to strengthen and replicate fibres , or as a consolidating surface. What we’re doing with it here is making replacement skin. With adhesive, it has a tightness and tautness just like skin.”

repair to bat specimen Careful repairs to a bat specimen using Japanese tissue.
Source: Museum Victoria
 

Karen Roberts and Brendon Taylor are restoring tiny bat specimens. It's painstaking work; they have pinned out the fragile wing membranes and patched the holes with Japanese tissue. The purpose of the specimen dictates the treatment from here. “A scientific collection item can have warts and all, with minimal intervention,” says Simon. “Here we could put a gentle lacquer to hide the tissue, but obviously for display you’ve got to colour them in.” The extent of treatment for exhibition work can be deceptive, as the conservation treatments aim to draw the eye away from repairs so the specimen can be read as a whole.

Two men with penguin specimen L-R: Preparator Dean Smith with Simon Moore, looking at a damaged King Penguin mount.
Source: Museum Victoria
 

Simon’s own knowledge comes from decades of experimentation and consulting with natural history collections around the globe. “I’ve learned lots myself throughout the years and I’m trying to advance the technology, giving credit where it’s due. There aren’t many people doing taxidermy conservation and they keep trade secrets.” The techniques that Simon shares in workshops like this will help keep scientific and display specimens in good nick for study, research and exhibitions in years to come.

Great Melbourne Telescope volunteers

Author
by Kate C
Publish date
13 March 2014
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Each Wednesday, a dozen or so engineering and astronomy buffs head to a museum workshop to restore one of Marvellous Melbourne's grandest marvels. The Great Melbourne Telescope (GMT), scorched by the Mount Stromlo fires in 2003, is being resurrected thanks to an estimated 10,000 hours of volunteer work (so far). This group recently received a Certificate of Appreciation in the 2013 Arts Portfolio Leadership Awards.

GMT restoration team Mathew Churchward reading out the Arts Portfolio Award commendation to the Wednesday restoration workshop team.
Source: Museum Victoria
 

The workdays have "a bit of a men's shed feel about them," says Senior Curator Matthew Churchward. He coordinates the project alongside Curator of Engineering Matilda Vaughan. The combined knowledge in the room – all members of the Astronomical Society of Victoria, many with experience in engineering, electronics, astronomy and optics – means this piece of 19th-century technology is in expert hands.

Three men with computer L-R: Barry Cleland, John Cavedon, new volunteer Norm and Stephen Bentley working on technical drawings of GMT parts.
Source: Museum Victoria

Building telescopes is a common pastime for amateur astronomers; volunteer Barry Adcock has a home-built a 14-inch diameter telescope for his backyard dome observatory, plus another telescope that allows him to view the stars from inside his house. For many, stargazing is a habit they picked up when very young. Scottish-born Jim Pollock recalls a lunar eclipse in 1949 during which the moon was bright blue after forest fires in Canada. "In the atmosphere, tiny particles of pinene, the oil from the pine trees, scattered red light beautifully and just let the blue light through." Another volunteer, Barry Clelland, remembers looking up as a kid from his backyard in the suburbs and thinking, "that's half the universe there. You could see the Milky Way in Heidelberg back then."

On this day, a sub-group is working on the mirror polishing and grinding machine, a beautiful hulking contraption with a cast iron frame and gears and shafts. The GMT's half-ton speculum metal mirrors tarnished over time, so every few years they were removed and reconditioned with this machine. "We're still trying to work out exactly how it was driven," says Matthew. The mirror sits on a rotating table and as it moves, the polishing head also rotates, "so it doesn't get a flat spot in any part of the mirror. It keeps moving as it's rubbing." Or, like "patting your head and rubbing your tummy," jokes volunteer David Linke. The team hopes to have the polishing machine working within the next year as a hint of what's to come with the telescope itself.

David Linke with the mirror polishing machine. David Linke with the mirror polishing machine.
Source: Musuem Victoria
 

In the workshop, parts of GMT are laid out on pallets and benches. With a grin, David says, "it's a big jigsaw puzzle, isn't it?" Above it all, for equal parts reference and reverence, hangs a large-scale historical picture of the GMT in operation.

Museum workshop A view of the workshop with the GMT’s lattice tube in the foreground. On the back wall hangs the large historical photograph of the GMT at the Melbourne Observatory.
Source: Museum Victoria
 

Most of the large parts of the GMT were recovered after the 2003 Mt Stromlo fires. "Oh golly, it was a dirty job to get everything out of that cube," recounts David. "The aluminium had melted from the dome and filled up the screw holes so you couldn't see where things were undone." Many months of work saw the GMT dismantled and its surviving parts audited. Fortunately, the GMT had an unofficial champion in Barry Clark, who has been involved with the Melbourne Observatory since 1955. At that time, decommissioned equipment went into storage and was at risk of being lost. Says Matthew, "Barry's been instrumental in recovering bits and pieces that were hidden under the floor. He's discovered some key bits of equipment that went right back to the very earliest observatory at Williamstown."

Detail of the dismantled cube of the GMT. Detail of the dismantled cube of the GMT.
Source: Museum Victoria
 

Lengthy reverse-engineering is recreating the missing parts. "We go out there with a ruler and pencil and paper, take measurements and sketch it up roughly," says Campbell Johns. The measurements are made in imperial units to match Irish manufacturer Thomas Grubb's original specifications, before conversion to metric for fabrication. Some of the team with technical drawing expertise convert the workshop sketches into digital CAD files. There's a lot of cross-checking with old photographs, drawings and the extant parts.

"We don't even know if there was ever a full set of working drawings," says Matthew. "It appears they did the basic layout and started building it before they had the detailed design. You can see evidence in the way parts were modified during the construction process, like spots flattened out of a casting to make a seat for another component." A volunteer adds, "Pretty amazing given in those days there were no angle grinders or power drills or oxy welders. It was all done with cold chisels."

Three men with computers L-R: Barry Clark, Barry Adcock and Mal Poulton working on optics design specifications for the GMT.
Source: Museum Victoria

So why are these men devoting their spare time to this project? It's evident from the way they talk about the GMT that they admire its history and innovation. In addition to its astronomical achievements, including the first observations of southern nebulae, the ingenious nature of its design bewitches them. It had two axes and counterweights that allowed just one person to move the beautifully balanced telescope. In its lifetime there were larger scopes, but none so nimble. Matthew's view is that it's an opportunity of a lifetime for amateur enthusiasts to build such a large telescope; few individuals would have the resources to do so alone. Other volunteers nominate restoring an important part of Melbourne's history as their prime incentive – they want to see it back in its old home.

Indeed, the end goal is to return the working telescope to the Melbourne Observatory for public viewings. Its original configuration restored, there may be new electronic additions to allow digital photography or remote operation via the web. As Matthew says "It could be very inspiring for astronomy in Victoria."

Links:

The Great Melbourne Telescope website contains the story of the telescope, and updates about its restoration through the ASV's Phoenix newsletter

Follow the GMT project on twitter: @GMT21stC

Great Melbourne Telescope on Collections Online

One-sixty

Author
by Kate C
Publish date
9 March 2014
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Harry Telford bought Phar Lap at auction for 160 guineas, back when Big Red was known only as "Good Walker, Great Shoulder, Very Strong Made Colt".

horse auction catalogue The page from the Annual New Zealand Thoroughbred Yearling Sales on 24 Jan 1928, with hand-written notes about Harry Telford's purchase. (HT 8465)
Source: Museum Victoria
 

There were 160 tradesmen working in the Engineering Workshops of the Kodak factory complex in Coburg.

Photo of Kodak workshop Men operating machinery in the Kodak Engineering Workshop, Coburg, circa 1963. (MM 95964)
Source: Museum Victoria
 

Harry Johns drove his famous boxing troupe around in a bright red, customised International AR 160 Series truck.

Harry Johns' boxing truck Harry Johns' boxing troupe truck. (SH 961969)
Source: Museum Victoria
 

This centuries-old English penny in our Numismatics Collection was given the registration number NU 160.

Edward 1 penny Penny, Edward I, England, 1280-1281 (NU 160)
Source: Museum Victoria
 

And today, Museum Victoria is 160 years old! On 9 March 1854, the Assay Office in La Trobe Street opened to the public. Surveyor-General Andrew Clarke arranged for two rooms on the first floor of the Assay Office to be aside for the new Museum of Natural History and its collections.

This letter from the Public Records Office of Victoria records the formal permission granted the newborn museum by Assay Master Dr Edward Davy. (We assume Clarke had taken the liberty of moving a few specimens in before the official word arrived.)

Letter from Assay Master Dr Edward Davy Copy of letter to Surveyor-General Andrew Clark from Assay Master Dr Edward Davy, 1854.
Source: PROV

Transcript:
Government Assay Office
Melbourne 28th Apr 1854
Sir,
In reply to your letter of 22nd inst enquiring what accommodation can be given at the Assay Office for receiving Specimens which may, from time to time, be forwarded to the intended Museum of Natural History, I have the honor to state that there are at present, two rooms on the first floor of the building disposable for the purpose referred to.
I have the honor to be, Sir, Your most Obdt Servant,
E. Davy
Assay Master

 

Now we just need to figure out how to fit 160 candles on a birthday cake... I think we're going to need two cakes.

Boy with two cakes Boy with two cakes on his third birthday, Prahran, 1942. (MM 110629)
Source: Museum Victoria

Smoky mouse update

Author
by Phoebe Burns
Publish date
25 February 2014
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Phoebe is a University of Melbourne Masters student supervised by Dr. Kevin Rowe at MV. She is studying post-fire distribution and ecology of the Smoky Mouse in the Grampians National Park.

In September 2013, I moved to the Grampians, pitched a tent and set out to see how the endangered Smoky Mouse, Pseudomys fumeus, was faring in the aftermath of the February 2013 Victoria Valley fire. After three soot-covered months, I’m back in Melbourne enjoying modern comforts like showers and instant boiling water.

Grampians landscape Grampians landscape
Image: Phoebe Burns
Source: Museum Victoria
 

I began my surveys at the site where, prior to the fire, we found a healthy population of Smoky Mice in the November 2012 Museum Victoria Bioscan. By September regrowing bracken ferns and eucalypts added a splash of green to the blackened landscape. In spite of the devastation, I caught several healthy Smoky Mice including some of the same individuals we’d caught the previous November! The ecological significance of this discovery alone was cause to celebrate.

Adult Smoky Mouse Adult Smoky Mouse on a burnt log
Image: Phoebe Burns
Source: Museum Victoria
 

Between my first capture in September and my final trapping night in December, I surveyed 46 sites in and out of the burn scar across the Victoria Range in the Grampians. At six of those sites, all within the burn scar, I found Smoky Mice living in the rocky habitats. The mice in these populations were not just surviving, they were healthy and breeding. I caught adults weighing as much as 70 grams but I also found tiny juveniles newly emerged from the nest weighing only 12 grams.  

Juvenile Smoky Mouse Juvenile Smoky Mouse
Image: Phoebe Burns
Source: Museum Victoria
 

While I was looking to find Smoky Mice, my trapping methods meant I also caught a number of other small mammal species (and a few reptiles). I was lucky enough to encounter Swamp Rats, Rattus lutreolus, Heath Mice, Pseudomys shortridgei, Agile Antechinus, Antechinus agilis, and Dusky Antechinus, Antechinus swainsonii. The highlights of my small mammal by-catch were two tiny Eastern Pygmy Possums, Cercatus nanus, that found their way into my traps.

Eastern Pygmy Possum Adult female Eastern Pygmy Possum
Image: Phoebe Burns
Source: Museum Victoria
 

The last three months were physically and mentally challenging, hiking up mountainsides in the rain and hail, being snowed on one day and sweating in the heat the next, but it was worth every unpredictable minute. I feel so privileged to explore the beautiful, rugged wilderness of the Grampians National Park and to have encountered so many remarkable species. The Parks Victoria staff provided a wealth of logistical and emotional support. It’s great to know that our parks are in such capable hands and that the Smoky Mice of the Victoria Range are thriving in spite of the fires.

Links:

MV Blog: Smoky Mice in the Grampians

Sea anemone feast

Author
by Michela Mitchell
Publish date
7 February 2014
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Michela is the first resident taxonomist of Actiniaria (sea anemones) in Australia. This title doesn't come with a ceremonial sash, but it should.

Photographed by Dr Julian Finn on a recent dive trip to Nelson Bay, New South Wales, this sea anemone is taking on a shrimp feast to rival that of an Aussie BBQ. 

Sea anemone A sea anemone, Phlyctenanthus australis, chowing down on a Hinge-back Shrimp, Rhynchocinetes serratus. There's also a photobombing chiton in the background.
Image: Julian Finn
Source: Museum Victoria
 

Little has been documented about the diets of sea anemones, particularly in Australia. These chance encounters and images help us understand these predominately sedentary animals (although, they can set a cracking pace if they so desire) and what role they play in the marine ecosystem. 

Sea anemones are opportunistic feeders that catch whatever food passes by. Prey is ensnared and then immobilised with specialised stinging cells (nematocysts) found in the tissue of sea anemones.

There are many different types of nematocysts and each has its own function; some are sticky for catching prey, some poisonous, others are used in self-defence. When feeding, the anemone extrudes its mouth and throat (actinopharynx) over the prey, sometimes completely enclosing it. The sea anemone then crushes and digests the food in the throat, which also acts as the gullet. Food waste is then ejected back out the mouth, which doubles as the anus.

Not all sea anemones are totally reliant on eating; some have a symbiosis with zooxanthellae (microscopic algae) that live in their tissues, and the sea anemone can use nutrients created by the photosynthesising algae.

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Updates on what's happening at Melbourne Museum, the Immigration Museum, Scienceworks, the Royal Exhibition Building, and beyond.

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