Australian dinosaurs

This post was revised in Aug 2021.

In this post I present a list of the recognised species, together with a summary of how much bone we have for each species. It is surprising how little material we build our picture of Australia’s dinosaurs from! I will also provide a map to plot the location of the collection sites for these specimens, this map will also map the location of known dinosaur tracks (footprints).

Dinosaur List

Evidence for Australian dinosaurs is scarce and the diversity maintained in the fossil record very narrow.  There is clearly room for more to be discovered! Australia has 22 recognised species of dinosaurs identified from bone fossils, a further 9 species are imputed from dinosaur tracks.

The majority of the information in the following table is derived from the Australian Age of Dinosaurs website.

Species	Bone fragments known
Atlascopcosaurus loadsi	several jaw fragments
Australovenator wintonensis	~30% of a skeleton: arms and hands, legs and feet, several back and belly ribs, the paired front halves of the lower jaw, and several teeth.
Austrosaurus mckillopi	six vertebrate
Australotitan cooperensis	partial skeleton consisting of a partial left scapula, partial left and complete right humerus, right ulna, the right and left pubis and ischia and partial right and left femora.
Diamantinasaurus matildae	~30% of a skeleton, forelimbs, hind limb, shoulders, pelvis and several vertebrate and ribs. Partial skull.
Diluvicursor pickeringi	a partial right shin and foot, and a nearly complete tail
Fulgurotherium australe	a partial femur
Kakuru kujani	one opalised shin bone
Kunbarrasaurus ieversi	a near complete skeleton, armour  and stomach contents.
Leaellynasaura amicagraphica	a number of partial skeletons, but insufficient to piece together one animal.
Minmi paravertebra	eleven vertebra, fourteen ribs and a partial foot
Muttaburrasaurus langdoni	partial skeleton: skull, jaws, some vertebra, partial pelvis and limbs
Nanantius eos	shin bone
Ozraptor subotaii	shin bone
Qantassaurus intrepidus	three lower jaws with teeth
Rapator ornitholestoides	a bone from the palm of a hand
Rheotosaurus brownei	forty vertebra, partial pelvis, complete back leg
Savannasaurus elliottorum	20-25% of a skeleton: several vertebrae, ribs, parts of the shoulder and sternum, partial front limb bones including a complete right front foot, most of the pelvic girdle, an ankle bone and one bone from the hind foot.
Serendipaceratops arthurcclarkei	an ulna (forearm bone)
Timimus hermani	two thigh bones
Walgettosuchus woodwardi	single vertebra from the tail
Wintonotitan wattsi	several vertebrae, rib fragments, chevrons, partial shoulders, forelimb, and hip bones.

Observations on names:

• two clearly recognise the sponsors who assisted with the digs, i.e. Atlascopcosaurus recognising the mining company Atlas Copco, and Qantassaurus recognising the airline QANTAS.
• Two have aboriginal rather than Latin names, Kakuru kujani, 'kakuru' is the name for the rainbow serpent, in the 'kujani' language.  Kunbarrasaurus, 'kunbarra' is a local aborignal word for 'shield'.
• One of them is named after the science fiction writer Arthur C. Clarke, Serendipaceratops arthurcclarkei.
• One of them is named after a character in Conan the Barbarian, Ozraptor subotaii.

Postage Stamps

Stamp collectors may recall two handsome mini-sheets that were released to celebrate Australian dinosaurs.  The first, printed in 1993, was produced by Peter Trusler an Australian artist who specialised in paleontological topics.  The second, printed in 2013, inspired by the first, was produced by New York artist James Gurney.  Gurney produced a video about his artistic practice during this project which is worth viewing. 

Peter Trusler's mini-sheet from 1993.
Image source

Jame Gurney's mini-sheet from 2013.
Image source

Notice that Timimus is depicted in both, but understanding about the taxonomy of the species had changed in the intervening years.  This has seen Timimus move from being considered an ostrich mimic to something closer to a Tyranosaur, this reflected in how this species is depicted. Ironically it is the Tyranosaur not the ostrich mimic that has the feathers.

Comparison of depictions of Timimus, separated by 20 years.
Image source

You may have noticed that three of the names in the stamps are not in the list above, Koolosuchus and Ornithocheirus do not meet the criteria for a dinosaur, the stamps do not indicate that they were considered dinosaurs merely that they were alive at the time.  

The record of an Allosaurus has also undergone revision. In 1993 it was thought that an Allosaurus had been found in Australia on the basis of one ankle bone. Allosaurus is an American dinosaur. That identification has now been revised, and Allosaurus is no longer recorded for Australia.

A Dinosaur Map

Below is a screen shot from my Google My Maps 'Australian Dinosaurs', within the map if you click on the location it will show the species identified at that site.  The geolocating is very coarse and does not represent the actual location of a certain dig (You will need to click on the link above not the picture).

Some dinosaur track sites are Australian tourist attractions. Two in particular the Dinosaur Stampede National Monument at Lark Quarry, near Winton, Queensland, and the Dinosaur Coast, near Broome, in Western Australia, are of particular note.

Track marks and dinosaurs are colour coded by age, Yellow = Cretaceous, Orange = Jurassic and Triassic = Red.

The Blaschka sea life models

Soft bodied animals are very difficult to preserve, which in part is why we have so few records of them in fossils.  Even in a preserving solution like formalin they sag and lose their colour.  What in life would have been an intricate interplay of shape and colour becomes an amorphous blob.  So it was with a sense of with wonder that I encountered the Blaschka sea life models, models of soft bodied marine life made from glass.  They went beyond giving a suggestion of an animal, to being art pieces of such precision they could be used to teach people how to differentiate one species from another.  In the case of the radiolarian models enabling otherwise microscopic organisms and details to be visible without magnification. 

The octopus below is just one of hundreds of marine organisms modelled in glass by the Blaschkas 150 years ago, and I imagine that for a person who knew their octopi this is easily identifiable to the species level.

A Blaschka octopus, probably Octopus vulgaris,  part of the Harvard collection.  Photo from the Boston Globe
https://www.bostonglobe.com/arts/theater-art/2014/07/26/blaschka-sea-creatures-exhibit-opens-harvard/G5zUYHgt4Inqlj8pIjuh8L/story.html

In this blog post I provide an annotated list of websites where my readers can explore Blaschka models for themselves. Consider this a belated contribution to World Oceans Day (7 June). If you find yourself falling down the rabbit hole of wonder at these models I am sure you have the skills to find your your way either back out or deeper in.

The makers

The father and son partnership of Rudolph and Leopold Blaschka made over 10,000 models spanning 700 species in the period 1863 to 1890 (Sarakas, 2016).

Leopold and Rudolph represent a long lineage of glass makers, dating back to Venetian glassmakers in the 15th Century (University of Dublin).

Their craft was not passed to another generation, and to this day some of the Blaschka techniques and skills have not be replicated, which I imagine is problematic for restorers.

The Blaschkas based some of their craft initially on drawings. Of particular note as sources of information for their models were the following works.  As they became more renowned they started to use actual specimens for their work.

• Philip Henry Gosse (1853) A Naturalist’s Rambles on the Devonshire Coast.  A digital copy is available at the Internet Archive.
• George Brettingham Sowerby (1857) A Popular History of the Aquarium of Marine and Fresh-Water Animals and Plants. A digital copy is available at the Internet Archive.
• Philip Henry Gosse (1860) Actinologia Britannica: a history of the British sea anemones and corals. A digital copy of this work is available at the Internet Archive.
• The works of Ernest Haeckel.  Including Radiolaria (1862) and others, many of these works are also available online.

Blaschka glass model photographed by Guido Mocafico (top) and watercolour of the same.
The creature is a blue dragon, Glaucus atlanticus, a small sea slug that feeds on jellyfish.  I think it was encountering a picture of a Blaschka model of one of these that started my fascination with the Blaschkas.  As a child I regularly encountered these blue dragons washed up on Queensland beaches.
Source: https://www.ucpress.edu/blog/21026/a-sea-of-glass-and-the-blaschkas-fragile-legacy/

The Blaschkas' skill is so exquisite that even photographs of their work can fetch high prices.  Of particular note is the work of Guido Mocafico.  If you compare Guido's "medusa" (jellyfish) photographs to his Blaschkas you will appreciate his clear fascination with the later [be warned if you appreciate photography you may get a bit lost on this site!].

The Collections

Australian Museum (Sydney)

The Australian Museum website has images of 43 anemone specimens.  The Australian Museum ordered their Blaschkas in 1879, displayed them until 1941, then moved them to museum archives.

This image of the sea anemone, Hormathia margarita, looks like belongs in a swanky cake shop.
Image:  Australian Museum. 

Cornell (US)

Cornell has a significant collection of Blaschkas.  Their online archive has images of 250 specimens, is well catalogued with both the scientific name and the Blaschka number of the model.

One of the locations within Cornell for the Blaschka models is the Corning Museum of Glass (CMOG). This article on Atlas Obscura  provides some details of CMOG's curation of the Blaschkas.

Cornell was also involved with the production of a film Fragile Legacy, which is available for download via Vimeo on demand.  The film focuses on both ocean conservation and the Blaschkas. There is a catalogue of an exhibition which accompanied the launch of the film. The online catalogue provides images of numerous models, some 3D viewable models,  and images of the paints and tools used to create them.  It also has a map detailing some of the locations for Blaschka collections and associated items (like sales catalogues).

Harvard (US)

Harvard has a collection of 430 Blaschka invertebrate models, with 60 on permanent display.  These form the basis of a recent book entitled Sea Creatures in Glass.  The website also has access to 3D scans of some models.  Harvard also houses the Blaschka glass flowers exhibit.

Natural History Museum (London, UK)

The NHM has 185 Blaschkas, they appear regularly in the institutions blog roll, enter Blaschka into the search panel to find these.  I recommend this Youtube video (6:22 minutes) which shows some of the NHM models and explains their conservation.

Radiolarians are a feature of the NHM Blaschka collection.  Much of the work brought the micro into the macro and would have been based on Heackel's work.  This is a specimen of Actinomma asterocantium.  Image: NHM.

University of Dublin (Ireland)

Has a collection of 400 Blaschkas.  There are very few photographs on their website and a number of the links to other collections no longer work.  However the text on the Blaschkas is informative.

Museum of Wales

Museum of Wales has a number of Blaschkas.  They appear in the following posts. [NB: I found the site was misbehaving on blog writing day].

• Spectacular glass sea creatures of the deep (2007)
• Sea creatures of the deep - the Blaschka glass models (2007)
• Repairing the irreplaceable (2007)
• The glass worms (2016)

Model of the jellyfish Physalia arethusa, a feature in 'repairing the irreplaceable article.
Image: Museum of Wales.

Astronomical names it's all Greek to me

I have recently finished reading Stephen Fry's (2017), Mythos: a retelling of the Myths of Ancient Greece (Penguin). The reading is easy and fun, with humour typical of Fry's stage presence and other writing.  To read Mythos was also to read a context for the nomenclature of space, a who's-who of astronomical objects and some present day constellations.  I place on my list of recommended reading for astronomy bluffs, though given its placement in a fiction genre it frustratingly lacks both a table of contents and an index.  Mythos is also a treasury for etymologically curious people as clearly Fry loves to understand words.  Read his footnotes, some gems in there also.

To prove the point that space is full of Greek names, I have compiled this summary from a more exhaustive list on the International Astronomical Unions site.  Also worth reading their guide to naming conventions, which describes how decisions are made about how things are named, including planetary features like craters.

The Planets

In English speaking astronomy the eight solar system planets bear the names of Roman gods (Uranus exempted), but is also worth observing that there is correspondence to Greek gods and therefore we could consider that the Greek god is also being referenced.  I have included Pluto and Ceres in the list, because even though they are no longer considered planets, they fit the pattern being described.  Table mostly derived from the Mythology for Dummies Cheat Sheet.  Ceres was discovered in 1801, labelled as planet and 'demoted' to an asteroids in the 1850s.

Roman	Greek	Description
Mercury	Hermes	Messenger of the gods
Venus	Aphrodite	Goddess of love
Gaea	Gaia	Earth
Mars	Ares	God of War
Ceres	Demeter	Goddess of the harvest
Jupiter	Zeus	King of Gods
Saturn	Cronos	Father of Zeus, Son of Uranus
Caelus	Uranus	God of the Sky
Neptune	Posidion	God of the Sea
Pluto	Hades	God of the Underworld

The Moons of the Solar System

The list that follows provides the name of the planet with the name of its moons as indented dot points, only Greek names make it to the list. Roman numerals follow the IAU convention and indicate the planet's orbit order (I assume). Once again I have included Pluto because it fits the pattern.

Earth

• The moon, Selene in Greek, hence the prefix Selenic for 'lunar' features.

Mars

• Phobos (I) - one of the horses that drew Ares chariot (translated 'fear').
• Demios (II) - one of the horses that drew Ares chariot (translated 'flight').

Asteroids

• Eros - god of love
• Ida - a nymph who raised Zeus
• Dactyl (I) - mythological beings who assisted Ida
• Kalliope -
• Linus (I) - 

Jupiter

• Io (I) - one of Zeus' lovers. Changed into a cow to protect her from Hera.
• Europa (II) - one of Zeus' lovers.
• Ganymede (III) - one of Zeus' lovers.
• Callisto (IV) - one of Zeus' lovers. Changed into a bear to protect from Hera.
• Amalthea (V) - naiad who nursed Zeus.
• Himalia (VI) - one of Zeus' lovers.
• Elara (VII) - one of Zeus' lovers.
• Pasiphae (VIII) - one of Zeus' lovers. Wife of Minos.
• Sinope (IX) - Zeus failed to seduce this character.
• Lysithea (X) - child of Zeus.
• Carme (XI) - one of Zeus' lovers.
• Ananke (XII) - one of Zeus' lovers.
• Leda (XIII) - one of Zeus' lovers.
• Thebe (XIV) - one of Zeus' lovers.
• Adrastea (XV) - cared for the infant Zeus.
• Metis (XVI) - one of Zeus' lovers, mother of Athena.
• Callirrhoe (XVII) - step child of Zeus.
• Themisto (XVIII)  - one of Zeus' lovers.
• Megaclite (XIX)  - one of Zeus' lovers.
• Taygete (XX)  - one of Zeus' lovers.
• Chaldene (XXI)  - one of Zeus' lovers.
• Harpalyke (XXII) -  one of Zeus' lovers.
• Kalyke (XXIII)  - one of Zeus' lovers.
• Iocaste (XXIV)  - one of Zeus' lovers.
• Erinomee (XXV)  - one of Zeus' lovers.
• Isonoe (XXVI)  - one of Zeus' lovers.
• Praxidike (XXVII) - one of Zeus' lovers.
• Autonoe (XXVIII)  - one of Zeus' lovers.
• Thyone (XXIX)  - one of Zeus' lovers.
• Hermippe (XXX) - one of Zeus' lovers.
• Aitne (XXXI)  - one of Zeus' lovers.
• Euanthe (XXXIII)  - one of Zeus' lovers.
• Euporie (XXXIV) - daughter of Zeus.
• Orthosie (XXXV) - daughter of Zeus.
• Sponde (XXXVI) - daughter of Zeus.
• Kale (XXXVII) - daughter of Zeus.
• Pasithee (XXXVIII) - daughter of Zeus.
• Hegemone (XXXIX) - daughter of Zeus.
• Mneme (XL) - daughter of Zeus.
• Aoede (XLI) - daughter of Zeus.
• Thelxinoe (XLII) - daughter of Zeus.
• Arche (XLIII) - daughter of Zeus.
• Kallichore (XLIV) - daughter of Zeus.
• Helike (XLV) - daughter of Zeus.
• Carpo (XLVI) - daughter of Zeus.
• Eukelade (XLVII) - daughter of Zeus.
• Cyllene (XLVIII) - daughter of Zeus.
• Kore (XLIX) - daughter of Zeus.
• Herse (L) - daughter of Zeus.
• Dia (LIII) - one of Zeus' lovers.

Saturn

• Mimas (I) - a Titan
• Enceladus (II) - a Titan
• Tethys (III)  - a Titan
• Dione (IV) - Zeus had sex with this person.
• Rhea (V) - a Titaness, mother of Zeus.
• Titan (VI) - a Titan.
• Hyperion (VII) - a Titan.
• Iapetus (VIII) - a Titans
• Pheobe (IX) - a Titaness.

|

• Epimetheus (XI) - son of Iapetus.
• Helene (XII) - granddaughter of Kronos. Her beauty triggered the Trojan War.
• Telesto (XIII) - daughter of Oceanus and Tethys.
• Calypso (XIV) - daughter of Oceanus and Tethys.
• Atlas (XV) - a Titan.
• Prometheus (XVI) - son of Iapetus.
• Pandora (XVII) - made from clay at the request of Zeus.
• Pan (XVIII) - god of pastoralism.

|

• Methone (XXXII) - daughter of the giant Alkyoneos.
• Pallene (XXXIII) - daughter of the giant Alkyoneos.
• Polydeuces (XXXIV) - son of Zeus and Leda.
• Daphnis (XXXV) - son of Hermes, brother of Pan.

|

• Anthe (XLIX) - daughter of the giant Alkyoneos.

|

• Aegaeon (LIII) - hundred armed giant.

Uranus

• Nothing here, all moons named after characters in Pope's "Rape of the Lock" or characters from Shakespearean plays.

Neptune

• Triton (I) - sea god, son of Poseidon and Amphitrite.
• Nereid (II) - collective term for the daughters of Nereus and Doris ... Poseidon's attendants.
• Naiad (III) - collective term for water nymphs.
• Thalassa (IV) - sea goddess.  Mother of Aphrodite or Telchines.
• Despina (V) - daughter of Poseidon and Demeter.
• Galatea (VI) - a nereid.
• Larissa (VII) - one of Poseidon's lovers.
• Proteus (VIII) - a sea god, son of Oceanus and Tethys.
• Halimede (IX) - a nereid.
• Psamathe (X) - a nereid.
• Sao (XI) - a nereid.
• Laomedeia (XII) - a nereid.
• Neso (XIII) - a nereid.

Pluto

• Charon (I) - the boatman who ferried souls across the river Styx.
• Nix (II) - goddess of dark and night, mother of Charon.
• Hydra (III) - monster of the underworld.
• Kerberos (IV) - nine-headed guard dog of the underworld.
• Styx (V) - goddess of the underworld.

Dwarf Planets

• Eris - goddess of discord and strife.
• Dsynomia (I) - daughter of Eris, spirit of lawlessness.

Most of the Solar system's moons (there are more than 180 of them) have been discovered in the last 30 years.  The fact that so many of them bear names tied to Greek mythology is not therefore a recognition of ancient knowledge but rather a scientific desire to have systems of naming for such objects.  I for one find such a name more interesting than an alpha-numeric code, which most of these objects would have had prior to gaining their Greek name.

All this amazing cast of characters, and I have not yet started on the stars, or the constellations that include them.  Nor the names of features, like craters, on the astronomical objects listed.  Both areas are rich sources for links to further Greek mythology.

Rescaling the Solar System

The task of this post is to present two resources that introduce students to a basic understanding of the Solar System, along with some ideas about how these resources could be utilised.  It contributes to the Year 5 Australian Curriculum (but is more widely useful) ...

The Earth is part of a system of planets orbiting around a star (the sun) (1) identifying the planets of the solar system and comparing how long they take to orbit the sun (2) modelling the relative size of and distance between Earth, other planets in the solar system and the sun (3) recognising the role of the sun as a provider of energy for the Earth. (ACSSU078)

A previously released resource, Solar System Happy Families (see previous post), may also be of interest.

‘The Hitchhikers Guide to the Galaxy’ says it beautifully

“Space," it says, "is big. Really big. You just won't believe how vastly, hugely, mind bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space, listen...”

But to grasp ‘how big’ requires us to play around with the scale of the objects in a system.  Because of the difference in magnitude of the planet’s size and the distances between them it is not possible to represent both in a diagram.  At best we need to use two scales, one for the planetary size and another for the distances between the planets.  Certainly any representation of the orbits of the planets that would fit in a book would have planets so infinitesimal as to be invisible if distance and size were the same scale.

To grasp both we can conceptualise the Solar System with scaled objects and then place them in the landscape, either in reality (using a walk or a drive) or imaginatively (using maps).  Such representations are a common science outreach tool.  For example, the Solar System Drive in NSW, is scaled so that the 37m dome of the Siding Springs observatory represents the sun.

The Neptune station on the Solar System Drive, NSW. A pull over point on the Newell Highway.

Deeper learning can be achieved if students work on representations based on their own imagining. Solar System Rescaler (link here) provides an online rescaling tool to achieve this.  Based on simple formulas, first written in Excel and now transferred to Google Sheets, the spreadsheet enables a user to enter the dimensions of an everyday object to represent one object in the solar system, for example, what if the Earth were the size of a marble?  The spreadsheet then calculates a scaling factor and rescales both the orbits and the object sizes of a number of nominated objects in the solar system.  Instructions and explanation of the formulas is provided in the supporting documentation linked to via the rescaler.

A couple of examples.

In my backyard I created a representation of the Solar System rescaled so that a 400mm bird bath could represent the sun.  Only the four inner rocky planets would fit inside my yard and I represented these with holes drilled into aluminium plates that I attached to the fence, thus the Earth was 3.6 mm in diameter and 42.8 m away from the bird bath. The furthest planet, Neptune, was 1.29 km away.  Amazingly at this scale, the nearest star, Alpha Proxima at 4 light years away would be represented as being 10,800 km distant from my bird bath.   And what is between us and our nearest star? Well… billions of tiny objects which are so small that on average we could consider the space as ‘empty’.  That is our nearest star! The furthest object visible to the unaided eye is 2.25 million light years away. Space is big!

Aluminium plate for Mars, planet size represented by the hole with orbit of the two moons, Phobos and Deimos, represented by scribed circles.

Lego produced planets for some of their Star Wars models and I like to play around with these in the classroom.  In part because Lego is a familiar object, and for many students is immediately associated with creativity, but also because it is big enough to allow for tactile engagement.

Lego planet element and Lego boulder, with an Australian fifty cent piece for scale.

I start with these two objects a Lego planet, representing earth, and a Lego boulder, representing the moon (the scaling is about right). Invite students to hold the two objects, estimating what they consider to be the correct distance apart to represent the moon’s orbit.  Most will nominate a distance under 600mm.  The true distance is closer to 2.6m.  Below is the output from the rescaler.

Screen grab from the Rescaler.  Note the entry of the planet’s size, 86 mm, in the rescaler column.  Also note that the object type filter is active and displays only planets, the sun and the moon.

It is then possible to ask the question, what if we scaled the Solar System so that the sun was the size of the Lego planet? Segueing from this I produced a postcard resource (link here) which encourages students to decorate a postcard for a Lego representation of the Solar System, asking the question, how big would the Solar System be if any planet were scaled to the size of the Lego element?

Students then research various metrics for the planets, daylength, orbital period, max and min temperature, number of satellites etc, etc.  This information could then be recorded on the card.

Postcard for Jupiter. On the left is a blank lego planet (full size) for students to decorate. On the right the planets name, planetary symbol and a 1:1,000,000,000 dot to represent the planet at that scale.

Suggested extension activities for the postcards include.

a) Having conducted the research into another planet, students could write an imaginative piece pretending they were on that planet and writing a postcard to a friend either on Earth or on another planet in the Solar System.

b) When Lego released the planet element, it was Star Wars themed.  Students could design a Lego build to go inside the planet element, together with an appropriate mini figure that could represent someone who may have been of influence in learning about the planet, or perhaps the god after whom the planet is named.

c) The postcards contain a scaled version of the Solar system (1 is to 1 billion) in the right panel of the card.  Students could lay these out around the school grounds and perhaps share their learning with another class who is not working on the unit.

If you invent other things to do with this please share - use the comments section below.

Solar System Happy Families

I am pleased to announce the release of my card game Solar System Happy Families.

Available

• here as a Google Doc (which will allow for editing of a copy) and,
• here as a PDF (which will eliminate any pagination or font problems).

Scope

Designed with the Australian Curriculum year 5 descriptor clearly in view

The Earth is part of a system of planets orbiting around a star (the sun) - ACSSU078

The game uses play to introduce various elements of the solar system, planets, moons of various planets, phases of our own moon, asteroids and trans-Neptune plutoids. It also allows students to get a feel for some of the types of space missions that have been launched, manned lunar landings, Mars rovers and missions to the outer solar system, and missions to interstellar space, there are 11 families of objects in total.

There are 44 playable cards in a deck, when we consider that the the solar system has over 180 moons and several thousand asteroids, and that we only listed Pioneer 10 and none of it predecessors it is clear that the game is a taster and not a definitive guide.  There is room for an educator to set the creation of 'expansion packs' as an enrichment tool, for example orbiter missions, Chinese missions, trojans, centaurs, craters on the moon, or moons of Uranus - all just suggestions.

Rule systems

The game can work with normal happy family rules, i.e. deal all cards to start and then call for the card you need.  I have preferred to use a hybrid of the rules of happy families and go-fish, that is start with five cards each and have a draw pile left over.  These rules are explained on one of the cards in the deck.  House rules will emerge if the game becomes popular and this is fine.

I have trialled this in a year 5-6 composite class and when asked for feedback I received the following.

"... Solar System Happy Families was a fun and educational game, because I didn’t know some of the moons, ... and planets, like Europa, existed until I played this game.  I liked the fact that it can be a calm, enjoyable and competitive game all at once.”  

The printable file gives 4 colours of cards backs to allow for multiple decks in one classroom, printing instructions and the source information for all the images used in the deck. All images are from Public Domain or Creative Commons sources.

Moist air is lighter than dry air

The title of today's post seems both self explanatory, in that we observe clouds to rise and counter intuitive in that when we add something to something else we expect it to get heavier.  So what's happening? We need three pieces of science knowledge to explain this: Avogadro's hypothesis; an understanding of the composition of air; and the concept of atomic weight.

Avogadro's Hypothesis states that equal volumes of gas at the same temperature and pressure contain the same number of molecules, regardless of the chemical composition of the gas. [1] Specifically that number is 602,214,150,000,000,000,000,000 (over 602 sextillion) molecules of gas in 22.4 litres of gas at a temperature of 0°C, and 1 atmosphere of pressure.  The number will vary depending on the temperature and the pressure.



Dry air is composed of four elements.  Nitrogen (78.08 %) in a two atom molecular form known as di-nitrogen.  This is a nitrogen atom bound to another nitrogen atom with three chemical bonds, it is so strongly bound together it effectively functions as an inert gas for most of the time. Oxygen (21%) in a two atom molecular form known as di-oxygen, an inert gas Argon (1%) which because it is an 'inert gas' would be present as single atoms.  Finally, there are trace amounts of other gases including carbon dioxide.

Atomic weight.  The weight of a molecule is determined by the weight of its constituent atoms, and the weight of the constituent atom is determined by the number of protons and neutrons in the nucleus, electrons are virtually weightless, protons and neutron have the same weight.  Hydrogen is the lightest atom, it contains one proton and no neutrons and therefore has an atomic weight of 1. Nitrogen has seven protons and seven neutrons and therefore an atomic weight of 14. Oxygen has eight protons and eight neutrons and therefore an atomic weight of 16.

Di-nitrogen and di-oxygen together make up 99% of the weight of a parcel of air so I will only consider the weight of these two elements.  Suffice to say that carbon di-oxide is heavier than both of these molecules.  Di-nitrogen has a weight of 14 + 14 = 28, di-oxygen has a weight of 16 + 16 = 32. Water is made of two hydrogen atoms and one oxygen atom and therefore has a weight of 1 + 1 + 16 = 18.

Given Avogadro's Hypothesis that the number of molecules is constant, for every molecule of water 'added' to dry air, one molecule of di-nitogren or di-oxygen will need to be subtracted.  This would be a weight saving of 10 in the case of di-nitogren, and a weight saving of 14 in the case of di-oxygen and therefore moist air is lighter than dry.

Therefore clouds can rise and the hydrologic cycle can exist.

[1] http://www.chemistry.co.nz/avogadro.htm accessed May 31, 2015.