SOLDIER CRABS ON DUTY

Imagine you are a soldier crab (Mictyris longicarpus) that lives in the inter-tidal zone along the east coast of Australia. Your job is to avoid getting eaten by shore birds while scouring the sand at low tide and cleaning it of detritus, like an army of vacuum cleaners.
You have been hiding in the sand under the water - up to 2 metres deep. Your temporary refuge has been a bubble of air (about 4 times your body volume) that you created around yourself as you quickly burrowed down in a clockwise corkscrew motion, by walking backwards with your right legs.
Now that low tide has occurred there's no time to waste -
Call the muster! Form into rank! Forward march! It's just as well you're not like other crabs - imagine the pathetic army with soldiers that could only walk sideways!
Hang on a minute. How are you supposed to complete your tour of duty if you keep breaking rank to run off and wet your gills like other crabs? No problem. You have been designed with not only gills but also lungs, adjacent but distinctly separate, to provide you with 90% of your oxygen requirements. In fact you are even capable of absorbing oxygen through the decalcified joints of your legs and absorbing moisture through the silky hairs on your abdomen. No toilet stops, drink breaks or even breathers for you!
What a very cleverly designed little soldier, and smart...
Without tide-tables, calendar and watch, you even know when the next low tide is due.
Wherever did you get your sense of time from?

Acknowledgements:

David P. Maitland, Arthur Maitland, Caroline Farrelly, Peter Greenaway, University of NSW
Photo credit: Tony Sullivan

QUICK-SET ROCK

No time to even finish your lunch!

Apparently there are 200 million fossils stored in museums worldwide and these are predominantly marine fossils recovered from the sedimentary rock which covers ¾ of Earth’s continental area ( plus most of the ocean floor). Scientists seem agreed that catastrophic flooding by sea water has occurred on all continents and that animals must have been rapidly buried in sediment to be preserved as fossils before disintegration occurred.
(Even children know this!)

So, do sedimentary rocks take millions of years to form? 

Actually, no. Cementing agents such as calcite (lime or Calcium Oxide) and/or silica (Silicon Dioxide) must be present with water; pressure facilitates the process by forcing out the water. 
These same agents are the major ingredients of Portland cement which has to have gypsum (Calcium Sulphate) added to.....SLOW the process.

How quickly can cement start to set?...after 15 minutes!

How quickly did Mt. St.Helens sediment turn rock hard?
In less than 5 years.

It's not rocket science...it's rock science!....that children easily understand. 

Pluto: 2 for 1

Hello….what have we here? 

Yes, two for the price of one and you can see this in real life - only if you have a powerful telescope and know where to look in the constellation of Sagittarius the Archer. 

Do you remember swatting for science tests with the mnemonic: "My Very Educated Mother Just Sent Us Nine Pizzas" for the 9 planets - 4 terrestrial (Earth-like), 4 gaseous and mysterious Pluto? 
Well you can forget the pizzas because they're now telling us that Pluto is too much of a misfit to be called a planet. It's much neater to just have 8 ‘peas in the pod’: 4 terrestrials and 4 gaseous, and demote Pluto to a dwarf planet or ‘TNO’- Trans Neptunian Object.                

The problem is the other ‘terrestrials’ aren’t really Earth-like, and the 8 planets certainly aren’t ‘peas in a pod’ but all very UNIQUE. (how come?)  No two planets are alike - but Pluto is just too unique!

Percival Lowell (1855-1916) looked for a Planet X that mistakenly seemed to influence the orbit of Uranus and Neptune.  Lo and behold!... a 22 year old amateur, Clyde Tombaugh found ‘tiny’ Pluto on 18 February, 1930. 
(The PL in ‘Pluto’ acknowledges Percival Lowell.)

So what do we know about Pluto?  

·       Believed to comprise rock and frozen methane
·       A methane atmosphere
·       Still active volcanically!  (The ‘god of the dead’ is not so dead!)
·       A retro rotation about an axial tilt of 122.53 degrees from its orbital plane
·       The coldest ‘planet’ in our solar system, at minus 225 degrees C  (cold enough?)
·       A solar orbit inclined 17 degrees, so elliptical that it passes inside the orbit of Neptune for 20 out of 248 Earth years
·       3 minor satellites known as: Nix, Hydra and P4

…and how about this?...     
In 1978, astronomer James Christy found Pluto had a sibling – a moon half its size, Charon (‘ferryman of the dead’), which orbits Pluto every 6.4 days and they constantly face each other in a ‘tidal lock’-
just like two angry brothers, very much alive, facing off for a fight in the freezer room!                                                                                                                                       

(Pssst!……..whatever did Jim’s wife, Char, think of having a frigid moon named after her?)

Downunder 'n' lost? Not with Southern Cross

It's early on Sunday, December 3, 1854 at Ballarat, Victoria. A flag depicting the Southern Cross in the night-sky has been hastily sewn together and now flutters in the breeze while miners quietly shelter behind a stockade on the Eureka gold diggings. Soon 22 miners and 6 troopers will die when government troops attack and disband the protest over unreasonable mining licences.

Unfortunately, if you're north of Florida, Mexico, Africa or India you will be unable to see the Southern Cross that now adorns the flags of Australia, New Zealand, Papua New Guinea and Western Samoa, so let's describe this beauty for you...                           

 

If we look in the constellation of Centaurus we find 2 brilliant stars on the centaur's left leg pointing towards 4 stars marking the corners of 'the Crux' with a faint 5th star in one quadrant.  One of these pointers is Beta Centauri known as Hadar, and the other is Rigel Kent - a multiple star system comprising Alpha Centauri A and B that orbit each other plus Proxima Centauri, the closest star to our solar system at 4.2 light years away. By the way, with a good pair of binoculars we find the ‘jewel box’ (Crux cluster) just to the left of the Cross.

If you imagine the foot of the cross extended south for about another 5 lengths, half way towards the brilliant star Achernar, you have found the South Celestial Pole.

Why are we telling you of this now? 

Every year on April 1, the Southern Cross is immediately North of the South Celestial Pole - at midnight! Every month after that the Crux reaches that position 2 hours earlier. 

Is this just a fluke of nature?...or is there some design in this?

So if it’s fine weather and I’m lost in the desert at night, with no idea of time or direction, who is the April fool?                                                           

 

 

Acknowledgements:  

Stellarium

John Mackay, Creation Research  

Eureka flag / wwos.ninemsn.com.au                                                                          

                                                                                              

 

Heron's Creek or Heron's Ocean?

 

Recently we drove south to enjoy afternoon tea with friends who live about 15 kilometres away. Imagine our surprise at seeing what often turns up in their paddocks behind the plough!  So what are large imprints of fossilised clam shells doing in mudstone in Heron's Creek hinterland, 20 metres above sea level and 13 kilometres from the Pacific Ocean?

ODD BALL: NEPTUNE

 

Guess which planet we've reached now?

We're 30 times further from the sun than Earth so solar energy takes more than 7 hours to reach this frosty place at minus 215 degrees C. Nevertheless this planet radiates 2.7 times more energy than it receives!

In fact, if you're looking for signs of life, how about the most violent winds of our solar system at up to 1500 kmh and a Great Dark Spot (the size of Earth) that comes and goes.

How did we find out about this one?  Galileo spotted this beauty through his new telescope but didn’t realize what he’d just seen.  

Once Uranus was discovered accidentally in 1781, its orbital behaviour led John C. Adams and Urbain J.J. Leverrier to cleverly calculate the position of this unknown planet - found within half an hour by Berlin Observatory in 1846 – over 230 years after Galileo! This oddity whose existence Science can't explain, is so far from the sun that it has just completed only one orbit since it was first identified 167 years ago.

We now know it has a faint 5 ring system and 11 moons including Triton, the coldest object in our solar system, spraying out nitrogen ice crystals 10 kilometres high as it orbits this planet - in reverse!

Would you agree Neptune is unique?

By the way, if you want to check for yourself using a high powered telescope, you’ll find Neptune in the constellation of Aquarius.

 

Special thanks to Class 5/6 – 2013, Beechwood Public School, NSW
Image credit: whyfiles.org                                                                                   

Sweet 'n' sour water lilies

This will be a brief iopna for a change but hopefully we'll discover more as we go...

Newcastle Airport...of all places!

Water lilies (Nymphaeaceae) have some very unique features:

·       they are adaxial - the stomata (mouth) for breathing are on the upper side, with about 460 per square millimetre 

(Stomata are typically on the underside of leaves to limit moisture loss)

·       some bloom by day, others at night
·       blue flowers are common in this group
·       the giant water-lily of the Amazon raises its temperature by 10 degrees C to attract insects and to make it doubly attractive, emits a strong scent varying between butterscotch and pineapple!

So who thought of warm 'sweet & sour' first?

Acknowledgements:  John Mackay,Creation Research  
daviddarling.info    
ehow.com   
Photocredit: Janette  Hornsey