July 25 - 31, 2021: Issue 503

The Water Dwellers: Pittwater in 1967

Published July 19, 2021 by NFSA Films

From the Film Australia Collection. Made by the Commonwealth Film Unit 1967. Directed by James Jeffrey. A study of the people living and working in the Pittwater area 25 miles north of Sydney.

Colour In Competition 

WIN over $200 worth of children's books.

All you have to do is:

  1. Download and print the Colour Your Lockdown Competition Sheet
  2. Colour in beautifully
  3. Fill in all the details and photograph and email to books@oldmatemedia.com
  4. Look out for a winning notification on 4th August 2021

Competition closes Sunday 2nd August at 11.59PM AEST.

T&Cs apply. Entry is open to Australian residents only.

Click the link below for more details.

oldmatemedia.com/colouringcomp


If you see something, say something: why scientists need your help to spot blue whales off Australia’s east coast

Shutterstock
Vanessa Pirotta, Macquarie University

Blue whales, the largest animals to ever live, are surprisingly elusive.

They’re bigger than the biggest dinosaur ever was, capable of growing over 30 metres long and can weigh over 100 tonnes — almost as long as a 737 plane and as heavy as 40 elephants. They also have one of the loudest voices, and can talk to each other hundreds of kilometres across the sea.

Why, then, are they so difficult to find in some parts off Australia?

My new research paper recorded only six verified sightings of the pygmy blue whale off Sydney in the last 18 years. Two of these occurred just last year. This blue whale subspecies is known to mostly occur along Australia’s west coast.

Rare sightings like these are important because pygmy blue whales are a “data deficient” animal. Every opportunity we have to learn about them is crucial to help us better protect them.

Blue whales down under

Don’t let its name fool you, the pygmy blue whale can still grow shockingly large, up to 24 metres in length. It’s one of two blue whale subspecies that occur in Australian waters – the other being the Antarctic blue whale, the biggest whale of them all at around 33 metres long.

A blue whale lunging for krill.

Unfortunately, historical whaling hunted blue whales to near extinction in the Southern Ocean. The Antarctic blue whale was depleted to only a few hundred individuals and, while they’re slowly bouncing back, they’re still listed as critically endangered by the International Union for the Conservation of Nature (IUCN).

In contrast, we know little about pre- and post-whaling numbers for pygmy blue whales. Their listing as a data deficient species by the IUCN means we don’t have a full understanding of their population status.

Blue whales can grow to around 30 metres, almost the same length as a 737 plane. Vanessa Pirotta, Author provided

One reason may be because blue whales are logistically challenging to study. For example, blue whales don’t just hang around in one area all the time. They’re capable of swimming thousands of kilometres for food and to breed.

They can also hold their breath for up to 90 minutes underwater, which can make them hard to spot unless they’re near the surface. To see them, people need to be in the right place at the right time.

This may require scientists to be on dedicated research vessels or in a plane to spot them, which can be expensive and weather-dependent.


Read more: I measure whales with drones to find out if they're fat enough to breed


This also makes learning about them much harder compared to other, more accessible species, such as coastal bottlenose dolphins.

To learn more about pygmy blue whales in Australia, marine scientists have developed a variety of techniques, including listening to whales talking, taking skin samples and satellite tagging.

While this work is useful, it has focused mainly in areas where pygmy blue whales are known to occur, such as southern and western Australian waters.

Pygmy blue whales are known to feed in the Perth Canyon, Western Australia, and between the Great Australian Bight and Bass Strait during summer. They most likely breed in the Indian and western Pacific Oceans during winter.

But we don’t know much about pygmy blue whale presence in other parts of Australian waters, such as the east coast.

Two bottle nose dolphins
Bottlenose dolphins are more commonly seen. Shutterstock

How can we conserve a species we know very little about?

Well, it can be tricky. The more information we know, the better we’re placed to assess their conservation needs. But focusing our efforts on species we know nothing about may require a conservative approach until we learn more.

Some would argue it’s better to protect a species we know needs our conservation dollar before spending precious resources on something uncertain.


Read more: Curious kids: do whales fart and sneeze?


Fortunately, Australia has some of the world’s best protection policies for marine mammals, including whales. This means a precautionary approach is already in place to protect these creatures.

Since blue whales are listed as a threatened species, they’re protected under Australia’s primary environment law, the Environmental Protection and Biodiversity Conservation (EPBC) Act.

And on an international level, Australia is a signatory to the International Whaling Commission (the global body for whale conservation) and the Convention on International Trade of Endangered Species (which ensures wildlife trade doesn’t threaten endangered species).

Two blue whales near a boat
Citizen science sightings help contribute to our understanding of blue whale distributions in Australian waters. Shutterstock

To help uphold this international and national protection, scientists must continue to learn more about data-deficient animals like the pygmy blue whale to help safeguard against known and future threats.

This includes collisions with ships, overfishing, entanglement with fishing gear, increased human activity in the ocean, and climate change, which may affect when and where whales occur.

We need extra eyes

There are more than 14,600 animal species listed as data deficient by the IUCN.

Some, like the pygmy blue whale, are poorly studied. One reason is because they’re cryptic or boat shy, such as the Australian snubfin dolphin.

Or, they might be tricky to see, such as the false killer whale, whose sightings remain irregular in Australian coastal waters. Opportunities to learn more about them occur when they become stranded.

A false killer whale pokes its head out of the water
False killer whales are another data-deficient marine animal. Shutterstock

So while citizen science sightings of pygmy blue whales may be rare off the Australian east coast, they do help contribute to our understanding of their distribution in Australian waters.

The two sightings of pygmy blue whales off Maroubra, Sydney, last year were within two months of each other. This was thanks to drones (flown under state rules).


Read more: Climate change threatens Antarctic krill and the sea life that depends on it


This prompted my research review of blue whale sightings off Sydney, which found citizen scientists made similar sightings in 2002 – the first official sighting from land off Sydney — and between 2012-14.

We don’t know exactly what type of pygmy blue whales these are (three distinct groups are recognised: the Indo-Australian, New Zealand and Madagascar groups). However, whale calls detected along Australia’s east coast in previous years suggest they’re most likely New Zealand pygmy blue whales, and they could have been heading to breeding waters north of Tonga.

So, the next time you are by the sea, keep a look out and tell a scientist via social media if you see something interesting. You just never know when the world’s biggest, or shiest, animal may turn up out of the blue.


Read more: Photos from the field: these magnificent whales are adapting to warming water, but how much can they take? The Conversation


Vanessa Pirotta, Wildlife scientist, Macquarie University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

After Dark Photo Competition: Northern Beaches

Here's a great new photo competition just for locals.

The Northern Beaches are one of the best places in Sydney to view the night sky and appreciate this wonderful asset.
Enter your image of the Northern Beaches taken between sunset and sunrise, go in the running for prizes, and share the beauty of the Northern Beaches LGA in a way not done before.

Proceeds from the event, go towards supporting the charity the Australian Dark Sky Alliance to support the ongoing conservation of the night time environment.
Entries close 1st September, 2021.


Details

Categories/Sections
There will be three categories of entry for the General section;
  1. Land – manmade and/or natural formations, wildlife, flora or fauna
  2. Sea – waterways, beaches, or marine areas, sea life
  3. Sky – aspects of the night sky, moon, starscapes, clouds or wildlife
  4. Junior – under 16 years featuring any one of these categories.
All entries must be taken within the Northern Beaches LGA.
Images may be taken within the past 2 years, but must be taken between sunset and sunrise.

There is a limit of six (6) entries per category per photographer.

Still images must be submitted as JPG files with the longest side having a dimension no greater than 4,950 pixels in Adobe 1998 colour space, and no larger than 5Mb file size.

Entry Fees
  • Entry fees are $20 for the first category entered and $10 for each subsequent category entered.
  • Up to six entries per category are permitted.
  • Fees should be paid by the PayPal gateway on the entry website. Credit and debit cards can be used on this gateway.
  • If entry payments are not received by the deadline, then the submitted entries will not be accepted for judging.

Conditions of Entry
Still images must be submitted as JPG files with the longest side having a dimension no greater than 4,950 pixels in Adobe 1998 colour space, and no larger than 5Mb file size.

  1. Entries will be accepted only from Australian residents of the Commonwealth of Australia and its Territories.
  2. There will be two sections of entry – General and Junior (18 or younger)
  3. There will be three categories of entry for the General Section; Portraying the night time environment featuring Land, Sea or Sky.
  4. The Junior Section is for photographers 18 years old or younger and will have one open category.
  5. All entries must be taken within the Northern Beaches LGA and must be taken between sunset and sunrise.
  6. Images can be taken at any time of the year on or after 1 September 2019.
  7. The top 5 images of each category will be judged by the organising committee and will be hung at the Studio, Careel Bay Marina for general public display.
  8. Photographers represented in the top 5 images of each category will be notified that they are in the top 20 images (15 September 17:00 AEST).
  9. There is a limit of six (6) entries per category per photographer.
  10. In the case of images with multiple authors, the instigator of the image will be considered to be the principal author and the one who “owns” the image. The principal author MUST have performed the majority of the work to produce the image. All authors MUST be identified and named in the entry form along with their contributions to the production of the image.
  11. Entries must be in digital form and will be accepted ONLY through submission via the dedicated website at: afterdark.myphotoclub.com.au
  12. To preserve anonymity, the submitted image files should not contain identifying metadata.
  13. For judging purposes, still images must be submitted as JPG files with the longest side having a dimension no greater than 4,950 pixels in Adobe 1998 colour space.
  14. All photographs must have been taken no more than 2 years before the closing date of entry.
  15. Entry fees are $20 for the first entry and $10 each subsequent entry. Fees should be paid by the PayPal gateway on the entry website. Credit and debit cards can be used on this gateway.
  16. If entry payments are not received by the deadline, then the submitted entries will not be accepted for judging.
  17. Photographers of the top 20 images (5 in each category) will be notified 15 September and images printed, framed and hung by the organising. Artists may choose to pay $55 for this service to be undertaken on their part or undertake printing and framing at their own cost. Images must be ready for hanging 17:00 (AEST) 29 September 2021.
  18. Images will be listed on sale during the exhibition at the artist’s discretion. $100 of the sale will be donated to the charity the Australasian Dark Sky Alliance.
  19. Winners for the Land Scape, Sea Scape, Sky Scape and Youth entry will be announced Thursday 30th September 2021.
  20. People’s choice will confirmed by popular vote throughout the exhibition and will be announced on Saturday 30 October, 2021.
  21. Submissions close at 24:00 (AEST) on Wednesday, 1 September 2021. No entries will be accepted past this date.
  22. All winners should make an effort to attend the presentation of the awards on 30 September 2021
  23. The winning entries will be exhibited for the entire Exhibition After Dark, at the Studio, Careel Bay Marina between 30 September and 2 November, 2021.
  24. Permission to reproduce entries for publication to promote the competition and exhibitions and dark sky-related events and activities on the northern beaches will be assumed as a condition of entry. The copyright of the image remains with the author, and we will try to ensure that the author is credited where the image is used.
  25. All entries must be true images, faithfully reflecting and maintaining the integrity of the subject. Entries made up of composite images taken at different times and/or at different locations and/or with different cameras will not be accepted. Image manipulations that produce works that are more “digital art” than true astronomical images, will be deemed ineligible. If there is any doubt about the acceptability of an entry, then the competition organisers should be contacted, before the entry is submitted, for adjudication on the matter at the following email address: marnie@darkskytraveller.com.au
  26. If after the judging process, an image is subsequently determined to have violated the letter and/or the spirit of the rules, then that image will be disqualified. Any prizes consequently awarded for that image must be returned to the competition organisers.
  27. The competition judges reserve the right to reject any entry that, in the opinion of the judges, does not meet the conditions of entry or is unsuitable for public display. The judges’ decisions will be final.
  28. Submission of an entry implies acceptance of all the conditions of entry and the decisions of the competition judges.

Key Dates
  • Entries Open: 24:00 (AEST) Sunday, 11 July 2021
  • Entries Close: 24:00 (AEST) Wednesday, 1 September 2021
  • Top 20 announced: 17:00 Wednesday, 15 September 2021
  • Photography bump in: Midday Wednesday 29 September 2021
  • Exhibition Launch and Presentation of Awards: Thursday 30 September 2021
  • Bump out – 2 November 2021
Prizes

The Overall Winner: To be judged by David Malin, Fred Watson

  • Category Winner: An image deemed to be the best in that category as judged by the judging panel.
  • “The People’s Choice”: This will be judged by gathering votes obtained in the exhibition venue, and online.
  • Category Winner: $200 – to each of the image deemed to be the best in each of the four (4) category.
  • “The People’s Choice”: $200 – will be judged by gathering votes obtained in the exhibition venue, and online.
There will be three categories of entry for the General section;

Land – capturing manmade and/or natural formations, wildlife, flora or fauna associated with the night
Sea – capturing waterways, beaches, or marine areas, sea life associated with the night.
Sky – capturing aspects of the night sky, moon, stars capes, clouds or wildlife associated with the night sky.
There is a limit of six (6) entries per category per photographer.

All entries must be taken within the Northern Beaches LGA.

The Junior Section is for photographers 18 years old or younger and feature any one of the categories.

More Information and enter at: afterdark.myphotoclub.com.au

2021 Crikey! Magazine Photography Competition

Now in its fifth year, Australia Zoo’s Crikey! Magazine Photography Competition encourages photographers from around the world to contribute their work to celebrate and illustrate the rich diversity of life on Earth and inspire action to conserve it.

Judged by award winning photographers including Robert Irwin, Georgina Steytler, Dudley Edmondson, Gary Cranitch and Kate Berry, this competition welcomes high-quality nature, wildlife and conservation images for a chance to win prizes and be exhibited at Australia Zoo and the Queensland Museum’s iconic Whale Mall right outside Queensland Museum in Queensland’s Cultural Centre, South Bank.

Entries open on World Environment Day, 5th June 2021, and close 31st August 2021.

Category One: Crikey! Magazine Cover
Our original category, the winning image will be featured on the cover of Crikey! Magazine. The image must be portrait orientated and have space for the magazine title (either above or below focal subject). The image should be captivating and feature an animal, photographed anywhere in the world. Images may include terrestrial or aquatic wildlife.

Category Two: Crikey! Kids
Our original category, the winning image will have a full-page featured in Crikey! Magazine. The image must be portrait orientated and should be captivating and feature an animal, photographed anywhere in the world. Images may include terrestrial or aquatic wildlife. To qualify for our Crikey! Kids category, entrants must be under the age of 15 year on 1 October 2021.

Category Three: The Natural World
This is the culmination of the three exciting categories introduced for our 50th Year celebrations. Images submitted to this category can showcase the natural world, depict the complex relationship between humans and nature, or illustrate threatened wildlife. It is through these images, that we can raise awareness and advocate for the conservation of wildlife and wild places!

Great Prizes
Five finalists will be selected from each category, along with a winner and highly commended. The finalists will all have their images exhibited within Australia Zoo and at external events. The images will also be featured in the Summer edition of Crikey! Magazine and all finalists will receive a personalised certificate.

There is a variety of exciting prizes to be won from each category, including vouchers, gift packs and Australia Zoo passes! Woo-hoo!

Crikey! Magazine Cover

Winner – Inclusion as the cover photo of Crikey! Magazine Summer edition, a CameraPro voucher to the value of $1,000.00 AUD and a signed Robert Irwin canvas print valued at $99.95 AUD.
Highly Commended – A choice of either an Australia Zoo family admission (2 adults, 2 children) including giraffe encounter; or an Australia Zoo signed gift basket to the value of $220.00 AUD.

Crikey! Kids

Winner – A CameraPro voucher to the value of $500.00 AUD and a signed Robert Irwin canvas print valued at $99.95 AUD.
Highly Commended – A choice of either an Australia Zoo family admission (2 adults, 2 children) including giraffe encounter; or an Australia Zoo signed gift basket to the value of $220.00 AUD.

The Natural World

Winner – A CameraPro voucher to the value of $1,000.00 AUD and a signed Robert Irwin canvas print valued at $99.95 AUD
Highly Commended – A choice of either an Australia Zoo family admission (2 adults, 2 children) including giraffe encounter; or an Australia Zoo signed gift basket to the value of $220.00 AUD.

How to Enter!
Step 1: Take your most creative wildlife photo that matches the theme of the category you are entering.

Step 2: Read the terms and conditions via the below link for clear guidelines of this competition.

Step 3: The photograph must be in portrait format for the Crikey! Magazine Cover category. Consideration needs to be taken to allow for the ‘Crikey!’ mastheads which will be positioned over the top quarter of the winning photo.

Step 4: All photographs must be provided in high resolution, 3:2 aspect ratio, JPG format and a minimum of 300 DPI. No borders, watermarks or signatures are allowed. Entries not meeting these requirements will not proceed to judging.

Step 5: Each photograph must be labelled with your name, category, subject of the photo and if required, a number for multiple images of the same subject. For example, an acceptable file name is JaneSmith_CrikeyKids_Lion or JaneSmith_CrikeyKids_Lion2.

Step 6: Enter via the links below from June 5 2021 to August 31 2021 to be considered. Age qualifications are – Under 15 Years on 1 October 2021 for Crikey! Kids entry and 15 Years & over for all other categories.

Step 7: A panel of judges consisting of expert photographers will choose the winners.

Step 8: Wait until 1 October 2021 to find out if you are one of our winners!

Entries close on 31 August 2021, so snap to it!

A $10.00 entry fee applies for each category excluding the Under 15 Years “Crikey! Kids”. The entry fees cover the majority of the competition administration costs to allow the proceeds from Crikey! Magazine to continue to provide essential support to Wildlife Warriors and make an immediate impact in the world of wildlife conservation.  Entry fees are non-refundable.

Canopy Keepers Art Challenge for pittwater's youngsters

Did you know that trees communicate using underground fungal networks? Or that, like us, they survive best in communities? 

There's lots to find out about the hidden life of trees and so Canopy Keepers are inviting Pittwater primary students to create an image that reveals an aspect of the hidden life of trees. Drawings, diagrams, painting, mixed media and photos are all welcome. Chosen artworks will be made into a calendar for 2022 for sale (to cover costs) in the local community. 

Get busy youngsters! Now is a great time to engage in a fun art challenge exploring our beautiful trees.

Email your work to cobbmilly@gmail.com by September 6th.


why are zebras stripy?

BBC Earth Kids:

what is the slowest thing on earth?

BBC Earth Kids: Published July 18, 2021

Yes Day by Amy Rosenthal

Published July 9, 2021 by Toadstools and Fairy Dust

The Tale of Peter Rabbit read by Rose Byrne

by Storyline Online - more Stories HERE

The Wiggles: making music!  

Published The Wiggles

Curious Kids: why do we need soap?

It’s a good idea to wash your hands after you go to the toilet, after you blow your nose, before you help prepare food and before you eat. Photo by Kelly Sikkema on Unsplash, CC BY
Mary-Louise McLaws, UNSW

Curious Kids is a series for children. If you have a question you’d like an expert to answer, send it to curiouskids@theconversation.edu.au You might also like the podcast Imagine This, a co-production between ABC KIDS listen and The Conversation, based on Curious Kids.


Why do we need soap? – Claire, age 4.


Thank you, Claire, for your question.

Soap is fun; it feels nice and slippery, you can blow bubbles with it and it often smells lovely. But it also keeps you healthy because it makes it easy for us to remove germs.

Germs are very very small, so small they are invisible to our eyes. We have many germs on our hands all the time. They like to live in the invisible layer of oil on our hands, and they particularly like to hide in skin creases and under your nails. There are many thousands and thousands of germs on your hands right now.


Read more: Curious Kids: why do spiders have hairy legs?


There are good and bad germs. Good germs live on your skin to keep it healthy. Bad germs – what scientists call “pathogens” – can make us sick.

We don’t know if bad germs are on our hands because you can’t see them. The best and easiest way to remove bad germs is washing them away with soap.

It’s a good idea to wash your hands after you go to the toilet, after you blow your nose, before you help prepare food and before you eat. Otherwise, when you touch your mouth, nose or eyes you might accidentally get a bad germ from your hands into your body – where it can make you very sick.

If you’re not a nurse or a doctor you don’t need to “kill” all the germs on your hands. You just need to wash the germs away. Soap is amazingly good at doing this.

Make sure you wash every nook and cranny of your hands. Flickr/World Bank, CC BY

Read more: Curious Kids: how do tongues taste food?


Soap gets foamy when we rub it with water between our hands. Foam makes it easy to move soap all around your hands and fingers. While we move soap around, it lifts up invisible oil that holds germs onto your hand. Under the running water we can easily wash off the soap, and all the invisible oil and germs along with it.

If you just use water without soap, the germs will stay on your hands. That’s because water alone can’t lift off the invisible oil where the germs are hiding, often tucked away in tiny creases in the skin on your hands.

We need to rub our hands together with soap and water long enough for the soap to do its job. We need to allow enough time for the soap to make foam, lift the oil holding onto the germs, and rinse them all away.

How long is long enough? Try singing the Happy Birthday song as you rub the soap and water between your hands. Flickr/Lucille Pine, CC BY

How long is long enough? Try singing the Happy Birthday song as you rub the soap and water between your hands, especially rubbing the soap and water over your fingers and fingernails where germs love to live. If you get through the whole song, you are giving the soap long enough to do its important job.

Don’t forget to rub your hands on a clean towel to remove any bad germs that could have been left on your hands.

When we wash our hands with soap and water, the soap lifts up both the bad and good germs and the water washes them away.

But don’t worry – all the good germs that keep your skin healthy will grow back very fast.


Hello, curious kids! Have you got a question you’d like an expert to answer? Ask an adult to send your question to curiouskids@theconversation.edu.au

CC BY-ND

Please tell us your name, age and which city you live in. We won’t be able to answer every question but we will do our best.The Conversation

Mary-Louise McLaws, Professor of Epidemiology Healthcare Infection and Infectious Diseases Control, UNSW

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Curious kids: how do gills work?

David Clode/Unsplash, CC BY
Culum Brown, Macquarie University

How do gills work? Tully, aged 7

Great question, Tully! Animals on land breathe air, which is made up of different gasses. Oxygen is one of these gases, and is made by plants (hug a plant today and say thanks). All animals need to breathe in oxygen to survive.

When the air goes into our lungs, oxygen goes into our blood and is delivered all around the body. Air is light, so it’s easy to move around. This makes it pretty easy to breathe air back and forth — a bit like blowing up balloons and letting them deflate.


Read more: Curious Kids: have people ever seen a colossal squid?


Things are different for fish. Fishes also need oxygen, but rather than getting it from air, they have to get it from water.

But there is less oxygen available in water than air. And to make matters worse for the poor fishes, water is thicker than air, so it takes much more work to move it around. This makes the problem of getting that oxygen in the fishes’ body even harder.

Two goldfish in an aquarium
Fish take in water through their mouths, where it passes over their gills. Shutterstock

This is why fish need gills

Rather than breathing in and out through the mouth, fish use a one-way system, passing water in one direction over their gills.

Water goes in the mouth, across the gills and out through the opercula (the bony covering protecting their gills).

But gills and lungs are more similar than you might think. Both have really big surface areas which increases the amount of water or air that touches the gill or lung tissue, and so increases the amount of oxygen available.

Water goes in the mouth, across the gills and out the other side. Shutterstock

What’s more, the walls of the lungs and gills are very thin and loaded with tiny tubes that transport blood (called “capillaries”).

This means the capillaries come into close contact with the air or water outside, letting oxygen pass across the thin walls and into the blood. At the same time, carbon dioxide, which is a waste product from our bodies, passes out.

Gills are also important for controlling how much salt is in the body, but let’s leave that story for another day.


Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to curiouskids@theconversation.edu.au


Read more: Curious Kids: when fish get thirsty do they drink sea water? The Conversation


Culum Brown, Professor, Macquarie University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Are there any planets outside of our solar system?

Artist illustration of an exoplanet. dottedhippo/iStock via Getty Images
Jean-Luc Margot, University of California, Los Angeles

Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to curiouskidsus@theconversation.com.


Are there any planets outside of our solar system? - Eli W., age 8, Baton Rouge, Louisiana


This is a question that human beings have wondered about for thousands of years.

Here’s how the ancient Greek mathematician Metrodorus (400-350 B.C.) put it: A universe where Earth is “the only world,” he said, is about as believable as a “large field containing a single stalk.”

About 2,000 years later, in the 16th century, the Italian philosopher Giordano Bruno suggested something similar.

“Countless suns and countless earths” existed elsewhere, he said, all rotating “round their suns in exactly the same way as the planets of our system.”

Scientists now know that both Metrodorus and Bruno were essentially correct. Today, astronomers like me are still exploring this question, using new tools.

An exoplanet orbiting a red dwarf star.
An exoplanet orbiting a red dwarf, a star that is dimmer than our Sun and about half the size. Mark Garlick/Science Photo Library via Getty Images

The exoplanets

There is now evidence that demonstrates the existence of “exoplanets” – that is, planets orbiting stars other than our Sun.

That evidence is based on the discoveries made by the Kepler space telescope, launched by NASA in 2009.

For four years, the telescope stared continuously at a single region of space within the constellation Cygnus.

Looking from Earth, it’s an area that takes up less than 1% of your view of the sky.

An illustration shows the Kepler telescope in space, next to a star and its planet.
Artist illustration of NASA’s Kepler space telescope. NASA Images

How the telescope worked

Kepler had 42 cameras on board, similar to the kind of smartphone camera that you use to take pictures. In that one region, the telescope detected more than 150,000 stars.

About every half-hour it observed the amount of light radiating from each star. Back here on Earth, a team of Kepler scientists analyzed the data.

For most stars, the amount of light stayed pretty much the same.

But for about 3,000 stars, the amount of light repeatedly decreased, by small amounts and for several hours. These drops in brightness happened at regular intervals, like clockwork.

The drops, astronomers concluded, were caused by a planet orbiting its star, periodically blocking some of the light that Kepler’s cameras would otherwise detect.

This event – when a planet passes between a star and its observer – is known as a transit.

And that means that in that one speck of space the Kepler telescope found 3,000 planets.

NASA Video: Animation of a exoplanet transiting its star.

That’s only the beginning

Although 3,000 planets sounds like a lot, it’s certain many others within that area remain undetected.

That’s because their orbits never blocked the light as seen by Kepler. After all, planetary orbits aren’t all the same; they’re randomly oriented.

But because of the number of transits observed by Kepler, and astronomers’ knowledge of geometry, we can make a good guess on the total number of exoplanets out there.

And after making those calculations, scientists now think, on average, that every star has at least one planet.

This discovery has revolutionized astronomy and our view of the universe.

NASA Video: Weird and Wondrous Worlds.

100 billion stars, 100 billion planets

For instance, our Milky Way galaxy has at least 100 billion stars; that means it has at least 100 billion planets too.

But remember: The universe holds up to 2 trillion galaxies. That’s 2,000,000,000,000! And each galaxy contains tens or even hundreds of billions of stars.

So the number of planets in the universe is truly astronomical, roughly equivalent to the number of grains of dry sand on every beach on Earth.

Some of those planets are gas giants, like Jupiter in our solar system. Others are boiling hot, like Venus. Others may be water worlds or ice planets. And some are Earth-like.

In fact, the Kepler team calculated the abundance of Earth-like planets in the “habitable zone,” a sector of space around each star where a world might have moderate temperatures and liquid water.

They found approximately 50% of Sun-like stars in the Milky Way host an Earth-like planet in the habitable zone.

That adds up to billions of potentially habitable worlds just in our galaxy.

NASA/JPL-Caltech Video: What is the “Habitable Zone”?

Could life exist elsewhere?

Although scientists haven’t found proof yet, many – including me – now think it’s unlikely that Earth is the only planet where life evolved. That would be as surprising as a large field containing a single stalk.

When will humans detect life elsewhere? Will it be intelligent life? Will people ever receive a message from another civilization?

Today, hundreds of scientists around the world are trying to answer those questions.


Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to CuriousKidsUS@theconversation.com. Please tell us your name, age and the city where you live.

And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.The Conversation

Jean-Luc Margot, Professor of Earth, Planetary, and Space Sciences, University of California, Los Angeles

This article is republished from The Conversation under a Creative Commons license. Read the original article.

 

Book of the month: July 2021 - The Amazing Adventures Of Dennis the Menace

1965 version

Archive of millions of Historical Children’s Books All Digitised: Free to download or Read Online

Enter the 1: Baldwin Library of Historical Children’s Literature here, where you can browse several categories, search for subjects, authors, titles, etc, see full-screen, zoomable images of book covers, download XML versions, and read all of the 2: over 6,000 books in the collection with comfortable reader views. 

Find 3: more classics in the collection, 800 Free eBooks for iPad, Kindle & Other Devices.


Dorothea Mackellar Poetry Competition 2021 entries now open

2021 OPTIONAL THEME: "RICH AND RARE"

''Our poets are encouraged to take inspiration from wherever they may find it, however if they are looking for some direction, competition participants are invited to use this year's optional theme to inspire their entries."

In 2021, the Dorothea Mackellar Memorial Society has chosen the theme “Rich and Rare.” As always, it is an optional theme, so please write about whatever topic sparks your poetic genius.

For a copy of the wonderful theme poster, please click here.

HOW TO ENTER

*PLEASE NOTE: If you're registering as an individual student, put your HOME address in your personal details and not your SCHOOL'S address! The address you list is where your participation certificate will be posted!*

ONLINE SUBMISSION

(primary school and secondary school, anytime during the competition period)

Teacher/parent - registration completed online (invoice will be emailed within 2 weeks of registration)

Log in to your page.

Enter student details and submit poem(s) (cut and paste or type in poem content direct to the webpage) PLEASE DO NOT UPLOAD POEMS AS ATTACHMENTS AS THAT FUNCTION IS FOR POSTAL ENTRIES ONLY.

Repeat step 3 for every student/individual poem.

PLEASE SEE HERE FOR A DETAILED PDF ON ENTRY INSTRUCTIONS FOR TEACHERS AND PARENTS.

USEFUL TIPS

Have a read of the judges' reports from the previous year. They contain some very helpful advice for teachers and parents alike!

It is recommended for schools to appoint a coordinator for the competition.

Only a teacher/parent can complete the registration form on behalf of the student/child.

Log-in details: username is the email address and a password of your choice.

Log-in details can be given to other teachers/students for poem submission in class/at home.

Log-in as many times as necessary during the competition period.

Teachers can view progress by monitoring the number and content of entries.

Individual entries are accepted if the school is not participating or a child is home schooled. Parent needs to complete the registration form with their contact details. Please indicate 'individual entry' under school name and home postal address under school address.

Invoice for the entry fee will be sent to the registered email address within 2 weeks.

‘Participation certificate only’ option available for schools where pre-selection of entries has been carried out. Poems under this option will not be sent to judges, students will still receive participation certificate for their efforts.

Please read the Conditions of Entry before entering. Entries accepted: March 1 to June 30, results announced during early September.

Visit: https://www.dorothea.com.au/How-to-Enter-awards


Profile: Ingleside Riders Group

Ingleside Riders Group Inc. (IRG) is a not for profit incorporated association and is run solely by volunteers. It was formed in 2003 and provides a facility known as “Ingleside Equestrian Park” which is approximately 9 acres of land between Wattle St and McLean St, Ingleside. 
IRG has a licence agreement with the Minister of Education to use this land. This facility is very valuable as it is the only designated area solely for equestrian use in the Pittwater District.  IRG promotes equal rights and the respect of one another and our list of rules that all members must sign reflect this.

WilderQuest online fun

The NSW National Parks and Wildlife Service is pleased to present the WilderQuest program for teachers, students and children.

The WilderQuest program includes a website and apps with game and video content, Ranger led tours and activities in national parks across NSW. It provides opportunities for families to experience nature, science and Aboriginal culture in classrooms, online, at events and in national parks. The Teacher portal and free primary school resources have been produced with support from our Environmental Trust partners.

LEGO AT THE LIBRARY

Mona Vale Library runs a Lego club on the first Sunday of each month from 2pm to 4pm. The club is open to children aged between seven and twelve years of age, with younger children welcome with parental supervision. If you are interested in attending a Lego at the Library session contact the library on 9970 1622 or book in person at the library, 1 Park Street, Mona Vale.

Children's Storytime at Mona Vale LibraryMona Vale Library offers storytime for pre-school children every week during school terms. Children and their carers come and participate in a fun sing-a-long with our story teller as well as listen to several stories in each session, followed by some craft.  

Storytime is held in the Pelican Room of the library in front of the service desk. Storytime is free and no bookings are required. 

Storytime Sessions: Tuesdays  10.00am - 11.00am - Wednesdays  10.00am - 11.00am  - Thursdays  10.00am - 11.00am

Profile: Avalon Soccer Club
Avalon Soccer Club is an amateur club situated at the northern end of Sydney’s Northern Beaches. As a club we pride ourselves on our friendly, family club environment. The club is comprised of over a thousand players aged from 5  who enjoy playing the beautiful game at a variety of levels and is entirely run by a group of dedicated volunteers. 
Profile: Pittwater Baseball Club

Their Mission: Share a community spirit through the joy of our children engaging in baseball.

National Geographic for Australian Kids

Find amazing facts about animals, science, history and geography, along with fun competitions, games and more. Visit National Geographic Kids today!

This week the National Geographic for Kids has launched a new free digital resource platform called NatGeo@Home to entertain and educate children affected by school closures.

The three main categories of content on the NatGeo@Home site aim to educate, inspire and entertain. For parents and teachers, there are also separate resources and lesson plans covering everything from getting to grips with Google Earth to learning to label the geological features of the ocean.

For the main Australian National Geographic for Kids, visit: www.natgeokids.com/au

For the National Geographic at Home site, visit:
Avalon Bilgola Amateur Swimming Club Profile

We swim at Bilgola rock pool on Saturday mornings (8:45am till 11:30am). Our season runs between October and March

Profile Bayview Yacht Racing Association (BYRA)

Website: www.byra.org.au

BYRA has a passion for sharing the great waters of Pittwater and a love of sailing with everyone aged 8 to 80 or over!

 Mona Vale Mountain Cub Scouts



Find out more about all the fun you can have at Mona Vale Mountain Cub Scouts Profile
– 

our Profile pages aren’t just about those who can tell you about Pittwater before you were born, they’re also about great clubs and activities that you too can get involved in!