Introducing Sam Jarman: Editor-at-large for Rising Ape Collective

profile sam jarman rising ape editorVeteran followers will have spotted the uptick in articles published on the RA site in the last couple of weeks. Now he’s got his feet under the WordPress dashboard, we can announce it’s all thanks to the efforts of Sam Jarman, the new editor for Rising Ape Collective.

Sam will be working with our roster of featured writers, including Anwen Bowers and Jon Farrow, as well as writing his own series on unanswered questions in cosmology. He may even be called upon to brutally edit that science poetry Antony keeps threatening us with. If you’d like to be hosted on the site, why not contact Sam about writing for Rising Ape.

We’ll let Sam tell you more about himself in time-honoured, RA style guide mandated, third person:

Having finished a Physics degree, Sam decided he was probably better at writing about science than researching it, and decided to take the lazy noble path of becoming a science journalist. He’s now taking the Science Communication course at UWE in Bristol, where he met the Rising Ape team.

Sam’s biggest interests in science are astrophysics and particle physics, which he likes to try and explain to people (even the parts he doesn’t really understand himself), most likely annoying them in the process. You’d think Brian Cox would be fearing for his job, but unfortunately Sam’s voice just isn’t soothing enough to become a suitable rival.

Sam’s favourite supersymmetric particle: The sstrange squark

The Audience gets Bristolians talking with algorithms

‘Really clever concept, good fun and I really liked the way the science is woven in!’ – Audience member

‘I feel grotty’ – Another Audience member

ALIC at the Bristol Improv Theatre
ALIX meets her latest data input devi- sorry, latest colleagues. | Image: Nick Moylan

After a busy 2016, Rising Ape squeezed one more event in before the end of the year. A freezing, foggy 1st of December saw a small, boisterous crowd weathering extreme elements, limited visibility and the Conan Doyle-ish Capital D dread of it all to make it down to the Bristol Improv Theatre. There, together they became the audience for, well, The Audience.

Guided by courtroom algorithm ALIX, the Audience became shaped into a cohesive unit, passing judgement on the sentence for a dramatic court case, and getting a glimpse into what justice in the future might be like. The immersive experience aimed to get people thinking about the consequences of trusting machines with our thoughts and biases. And all through the brandishing of LED lights and making friends with a slightly sarcastic A.I.

The Audience discussion theatre bristol
“I, for one, welcome our new AI overlords” proclaims controversial, yet out of shot, audience member, to everyone’s amusement. | Image: Nick Moylan

After the interval, the energised group began a passionate discussion with a panel consisting of:

  • Dr Sabine Hauert, Lecturer in Robotics at the Bristol Robotic Laboratory
  • Andrew Charlesworth, Reader in IT & Law at the University of Bristol
  • Dr Rosie Clark, Research Associate in Experimental Psychology at the University of Bristol
  • Antony Poveda, Producer for Rising Ape Collective and member of the cast.

Together the experts and audience discussed how far we are willing to trust algorithms with important decisions, personal experiences of the effectiveness of juries, and how little society is aware of the companies behind the technology we give data to. The engaging and highly productive session was filmed and we’ll be publishing the full video later in the New Year.

This production of The Audience was also incredibly valuable from our viewpoint. Learning from the performance at Green Man, we took the opportunity to tighten the script, take advantage of the new venue to really up the atmosphere (the mist certainly helped a bit there), choreograph new immersive moments, and, best of all, discover how well the performance works as a stimulus to get an audience talking with experts about these timely issues.

Want to experience The Audience for yourself? Follow us using the button below and look out for news of performances in 2017, as well as the film of the panel discussion, coming soon.

Y is for You!

It’s been 25 weeks since we started this epic journey through the alphabet together, and sadly we are nearing the end.  At this critical juncture, just one letter away from the finality of zed, I thought I would bestow my Pharaoh powers on to you, dear readers.

Comment below with your burning science questions, and I will answer them all next week in my final ABCs of Interesting Things post.

Thank you for reading.  I leave this quest in your very capable hands.

357px-Uncle_Sam_(pointing_finger)
I want YOU to ask me questions

For those still aching for some interesting science facts, how about these “you” facts:

There are more bacterial cells in and around you than human cells.

All of the atoms in your body were made inside stars, as the great Carl Sagan said the 1980 TV Series Cosmos: “The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies, were made in the interiors of collapsing stars.  We are made of starstuff.”

X is for Xenophobia

By Jonathan Farrow from the Thoughtful Pharaoh

A lot happened in the summer of 1954.  The world’s first atomic power station opened in Russia, Alan Turing committed suicide, the CIA set up a coup in Guatemala, food rationing finally ended in the UK, and the first edition of Sports Illustrated was published.  Some pretty big world events, right?

You know what else happened?  22 white, middle class boys boarded a bus to a Boy Scouts of America camp in Oklahoma.  And I’m going to tell you why you should care that they did.

The Robber’s Cave Experiment

On one (presumably sunny) day in 1954, two busses each picked up eleven 11-year-old children who had been screened to be “normal” (Remember, this was 50s America, so that meant white, protestant, middle class, two parents, above-average test scores) and who didn’t know each other.  The busses drove their “normal” boys to a summer camp called Robber’s Cave and deposited them on opposite sides, each group not knowing that the other existed.

For about a week, under the careful surveillance of psychologists posing as counsellors and camp staff, they participated in group bonding activities.  [In some ways, ethics boards have made psychology a lot more boring.  At the same time, it’s probably better that we now consider it unethical to Truman-show 22 pre-teens].

They camped out, played baseball, went swimming, and generally got to know each other.  They even came up with a name for their groups and emblazoned insignia on their t-shirts and caps.  One group killed a snake by a river and dubbed themselves the Rattlesnakes, the other group decided to be patriotic and called themselves the Eagles.

Then came the interesting part.

The experimenters introduced the groups to each other.

The Eagles and the Rattlesnakes were pitted against each other in a series of competitions – baseball, touch football, tug-of-war, and a treasure hunt.  The key aspect of these games was that one group always won and the other lost.  They were zero-sum games.

The result was a little bit scary.  The groups started to hate each other.  It started off with names like “sneak”, “cheat”, and “stinker” but soon developed into cabin raids, flag-burning, and even one Eagle telling another to brush the “dirt” of his clothes after bumping into a Rattler.  There was some serious xenophobia (fear or disgust for the “other” or “alien”).  The experimenters stopped the activities for fear of escalation to serious violence and started to think about how they might eliminate this extreme prejudice.

The crazy part is that these were all “normal” boys who didn’t know each other beforehand and had no reason to hate each other besides that their groups (that had also only been formed weeks ago) were in direct competition.

The experimenters tried to bring the groups together at mealtimes and for positive evening activities, but that only served to escalate the hatred.  They hurled food at each other at dinner time and jostled to be first in line.

What the experimenters tried next was pretty genius.  They got the groups to try and work together to solve problems that affected everyone.  One night the truck that was supposed to deliver food “broke down” so they all teamed up and pulled it out of the ditch with their tug-of-war rope.  Another day, the water supply pipeline broke and they all worked together to find the leak. These superordinate (larger than the group) goals brought the Rattlers and Eagles together.

Inter-group relationships built because of these events and at the end of the camp, some campers asked to mix up the busses and one group that had won $5 in a competitive contest offered to buy milkshakes on the ride home for the whole group.  How nice.  They had been reconciled as easily as they had been set against each other.

A 1997 study showed how this sort of reconciliation can be contagious.  It isn’t just people who have friends in other groups who will be more likely to be empathetic.  If you know someone who has friends in another group, you will be more likely to be nice to people in that group.  Sounds a bit complicated, but basically if you have a friend who is a clown, it’s not only you who will be more likely to not hate clowns, but also all of your friends.  As soon as a few Rattlers got to thinking that maybe the Eagles weren’t so bad, the positive feelings probably spread pretty quickly.

Chemical Basis for Xenophobia

But what was going on in their brains to make this happen?

Don’t worry, the kids weren’t lobotomized to find out.

A 2010 Dutch study out of the University of Amsterdam showed that Oxytocin, the “cuddle chemical”, might have something to do with it.

Research subjects who had ingested some Oxytocin were more “ethnocentric” than their placebo-munching counterparts.  People with a bit of extra Oxytocin in their systems were more likely to say they would sacrifice the lives of many outgroup members to save the life of one ingrouper and associated more positive, human words with ingroupers and more negative, dehumanizing words with outgroupers.

The Robber’s Cave Experiment was one of the first field experiments in social psychology.  It inspired Philip Zambardo’s Stanford Prison Experiment and Stanley Milgram’s Obedience Experiment.  It pushed people to consider why they acted in bigoted ways and showed how easy it can be to both turn people on each other and bring them back together.  When we mistreat people who belong to different racial/social/economic groups, are we really being any more than rational than the Eagles and Rattlers? No, we aren’t.

To find out more about the Robber’s Cave experiment, read this summary article by the leader experimenter, Muzafer Sherif, and this webpage.

Muzafer Sherif is also famous for a series of studies using an interesting phenomenon known as the autokinetic effect.  he showed that people will create group norms and stick to them even when the group is taken away.

W is for Wasps

It’s summer time.  And you know what that means? Sure, summer means picnics, barbecues, and sun.

But it also means the coming of the most dreaded outdoor villains: wasps.

Some people freeze up when they see the stripey serial stingers, others try to wave them away.  I prefer the stoic strategy of a short, sharp yelp followed by a crazed hand-waving motion.  It’s not a conscious decision, nor one that I am proud of, but the wasps seem to get the idea that I don’t want them around.

What is a wasp?

Wasp_morphology.svg
Image by Stannered

In taxonomic terms, a “wasp” is any member of the suborder Apocrita that isn’t a bee or an ant.  While that may help useful for biologists, it doesn’t really tell us anything about the creatures.

Wasps are a varied group of hairless, six-legged flying insects that measure anywhere from to 1mm (Fairy Wasp) to 4.5cm (Japanese Hornet).  There are thousands of species of wasp, many of which are specially adapted to feed on and parasitize insects we would regard as pests.

Parasitism

And the way they parasitize those pests can be cruel indeed.  Some parasitoid wasps lay their eggs inside their prey, only to have the eggs hatch a few weeks later, letting their young eat their way out of the unsuspecting caterpillar that has been feeling a strange itch recently.

Other wasps lay their eggs inside plants, genetically modifying a plant’s seeds to suit the wasp’s needs.

Still other inventive wasps have figured out that they can lay their eggs in the nests of other wasps and trick another queen into raising their young.

It seems there is nothing a wasp won’t lay its eggs in.

Fighting Wasps

Not all wasps are content merely laying eggs in unusual places.  Some have acquired a taste for honey.

Meet the Japanese Giant Hornet.

While European honeybees haven’t developed defenses, asian honeybees have discovered a way to fry invaders.

So while you may just think of them as a nuisance when you’re trying to enjoy your picnic, remember that with wasps, there is more than meets the eye.

V is for Vitruvian Man

VitruvianThis drawing, of a man contained within a circle and a square, is one of the most recognizable in the world.  It seems to fascinate people and has a way of transcending time and space to connect with its viewers.  It also is really easy to parody.

The original document, pictured above and created by Leonardo Da Vinci, has two major components: the drawing itself, and two paragraphs of writing.  Both deserve some attention, because while this image is rather commonplace in our culture, most people don’t realize how many layers there are.

Vitruvius

First off, why is the drawing even called the “Vitruvian Man”?  Is Vitruvius a place or something?

That was my first thought, but it turns out that Vitruvius was a man.  Vesuvius = volcano, Vitruvius = man.

Vitruvius was a roman architect whose ten-part treatise on architecture, De architecura, was the only document about architecture to survive from antiquity.  This means we owe much of our knowledge of the theory behind Roman aqueducts, central heating, and water pumps to this book. It is also the source of the (possibly apocryphal) story of Archimedes, his discovery in a bathtub, and his shout of “Eureka!”.

Vitruvius held that the three basic elements of good architectural design were strength, functionality, and beauty.  These elements are so important that they remain mainstays of modern architectural theory.  He was also especially interested in proportion.  He believed that ‘beautiful’ proportions were those based on nature.  And what more perfect example of nature was there than Man?

He believed that a perfect male body would fit the following conditions and that these proportions could be used to design perfect buildings.

For if a man be placed flat on his back, with his hands and feet extended, and a pair of compasses centred at his navel, the fingers and toes of his two hands and feet will touch the circumference of a circle described therefrom.

And just as the human body yields a circular outline, so too a square figure may be found from it. For if we measure the distance from the soles of the feet to the top of the head, and then apply that measure to the outstretched arms, the breadth will be found to be the same as the height, as in the case of plane surfaces which are perfectly square.

-Vitruvius’ De architectura

And then his writings were lost for more than a thousand years.

They were re-discovered in the 1400s in Italy and gained traction amongst Renaissance artists.

The drawing

And which Renaissance artist should be more intrigued by the challenge of drawing Vitruvius’ man than Leonardo Da Vinci, the namesake of everyone’s second favourite Ninja Turtle?

It's ok Leonardo, you may be my second favourite Ninja Turtle, but you'll always be my favourite Renaissance painter.
It’s ok Leonardo, you may be my second favourite Ninja Turtle, but you’ll always be my favourite Renaissance painter.

Da Vinci realized that in order for Vitruvius’ description to work, the centre of the square needed to be lower than the navel.  This lateral thinking separated Leonardo from other artists whose attempts to keep the same centre for both shapes made their men look strange.

cesariano-vitruvius-1 De_Architectura030

The other thing that separates Da Vinci’s Vitruvian Man is the dual positioning.  It gives a sense of movement to the piece as if it is an early kind of animation.  One unfortunate consequence of this is that the drawing doesn’t render very well in 3D and looks kind of like an alien:

An alien through the trees!  Image by Matt Brown
An alien through the trees! Image by Matt Brown

The writing

The drawing itself certainly draws a lot of attention, but few take the time to look at the writing.  This is partially because it is in illegible script, and the script is triply illegible to me.  First of all, I’m just bad at reading old, faded cursive script.  Second, it’s in Italian and I don’t understand Italian. Third, and most interestingly in my opinion, it’s written in mirror writing.  Why he did this is unknown, but it might have helped him avoid smudging as he wrote with his left hand.

The content of the paragraphs describe all of the proportions present in the drawing.  For Da Vinci (and Vitruvius), the distance between the tip of the fingers and the elbow is called one cubit and it is exactly six times the width of a palm and one quarter the height of a person.

There are 15 such proportions below that I encourage you to try out.  How do you measure up to the Vitruvian Man?

  • the length of the outspread arms is equal to the height of a man
  • from the hairline to the bottom of the chin is one-tenth of the height of a man
  • from below the chin to the top of the head is one-eighth of the height of a man
  • from above the chest to the top of the head is one-sixth of the height of a man
  • from above the chest to the hairline is one-seventh of the height of a man.
  • the maximum width of the shoulders is a quarter of the height of a man.
  • from the breasts to the top of the head is a quarter of the height of a man.
  • the distance from the elbow to the tip of the hand is a quarter of the height of a man.
  • the distance from the elbow to the armpit is one-eighth of the height of a man.
  • the length of the hand is one-tenth of the height of a man.
  • the root of the penis is at half the height of a man.
  • the foot is one-seventh of the height of a man.
  • from below the foot to below the knee is a quarter of the height of a man.
  • from below the knee to the root of the penis is a quarter of the height of a man.
  • the distances from below the chin to the nose and the eyebrows and the hairline are equal to the ears and to one-third of the face.

To learn more about this topic, watch this BBC documentary (part 1, part 2) on the subject that inspired this post.

Eruption Ft. Nicky Young

03/06/15 7.30pm, Bristol Improv Theatre, £3.50 entry

“What was that?” gasped Carol, one of Rising Apeton’s oldest residents. She’d been hearing worryingly strange rumblings for weeks. This was partly down to her astute, matriarchal, cautious nature; but also the amusing fact that ever since she’d sent her hearing aids in for service, they were now so sensitive she could even pick up three channels of Croatian TV. “It’s nothing, you’re hearing things again you old bat,” barked her ogreish neighbor. But Carol wasn’t that old, and if she were a bat she’d have been smart enough to leave this damned place long ago. What Carol had been hearing was the murmuring of Risuvious, the apparently dormant volcano that lay at the centre of the Bristol ‘Bubbling Cider’ fault line. The birds had left weeks before, but in their arrogance the clever humans had stayed far too long. The end drew near for Rising Apeton…

eruptionflyer

Rising Ape returns with a real lava palaver! What’s your mission? To work out how to save Rising Apeton. As always, you’ll need your best quiz heads on, and of course the winning team will get a sizzling prize. The night will end with an incandescent talk from bubbling volcanic researcher Nicky Young. So come along, grab a drink, and get planning!

Nicky Young studies volcanoes as a PhD candidate at the University of Bristol. An early love of rock-hounding and geology-based movies such as Dantes Peak, Volcano, and Journey to the Centre of the Earth (factual or not as they may be) led her to beginning a Geology MSci at Bristol 6 years ago. This was followed by a 6 month stint in Hawaii at the Volcano Observatory where Nicky explored the signals Kilaeau volcano emitted to try and discern volcanic movement. Since then studying volcanoes has been her passion, which is why she returned to Bristol for a PhD. She studies the movement of active volcanoes to understand what is happening deep below our feet.

Location: Bristol Improv Theatre, St Pauls Road, Bristol, BS8 1LP

Ticket Price: £3.50 on the door or available online from the Bristol Improv Theatre website

Time: 3rd June 2015. 7:30pm – 10:00pm

Vegetarian aliens could save our bacon

By James Riley

Bacon is tasty, very tasty. It’s so tasty that my moral objection to the industrial-scale murder of sentient animals dissipates with each and every ketchup-soaked bite. This is a weakness on my part. I’m theoretically ethical but practically perverse. It’s a great way to be. You get to rest your nose on the edge of the moral high ground, whilst your body swings in the succulent depravity below. But in all sincerity, I would argue that an extension of vegetarian philosophy is the only possible way we could survive an encounter with extra-terrestrial life. Let’s just hope astro-porcine is less alluring.

hungry aliens eat space pig rising ape
They came for a piece? (Image: Bell and Jeff/Flickr)

I’m pretty optimistic about alien life, not only about its existence but also about its intelligence and intentions. As unnerving as it is to disagree with such a great man, I must confess I don’t share Stephen Hawking’s view: “If aliens visit us, the outcome would be much as when Columbus landed in America, which didn’t turn out well for the Native Americans.”

stephen hawking right about nasty aliens
(Image: Mike Licht/Flickr)

On earth, species have certain ecological niches, their relational position to other species and their way of life in an ecosystem. Interplanetary, interstellar or even intergalactic life may follow a similar pattern. What niches come down to is competition for resources in a given environment. If one day we do share an interstellar environment with other intelligent species, there will no doubt be different ways of ‘making a living’ between the stars. But as soon as competition for resources enters the equation, we have a problem.

If aliens come here to harvest a resource that we also depend on, then we will undoubtedly lose due to the competitive exclusion principle. According to this principle, also known as Gause’s Law, two species that are competing for the exact same resource cannot stably coexist. Furthermore the species with even the smallest competitive advantage will be successful in the long run. As the aliens will have traversed interstellar space to reach us, our technology and defence capabilities just won’t match up. ET, I’m sad to say, will be holding a horribly beweaponed stick.

cavemen make fire
“Hm, maybe we should start building a bigger stick now…” (Image: Lance Cpl. Nathan McCord/Wiki)

But there’s another scenario. In this case the outcome of an extra-terrestrial meeting isn’t solely left to the will and whim of evolutionary forces. Instead, as has happened in our civilisation, rational choices can overcome biological impulses.

Take eating meat for example. It is generally accepted that our ancestors ate meat in their hunter-gatherer existence. But nowadays some people have come to the conclusion, to the upmost resentment of others, that killing animals and eating meat might be a tad wrong. You know, all the confinement, force-feeding, mechanised slaughter, it is a little unsettling (until you taste the bacon). Others argue the opposite, that eating meat is ‘natural’ therefore it must be the ‘right’ thing to do. This line of reasoning commits my favourite logical fallacy (don’t pretend you haven’t got one), the ad Naturam or appeal to nature logical fallacy. If we solely took our morality from nature we would live in a very cruel world indeed. (Watch a video of Mallards being natural here. Note: Morality not included; viewer discretion is advised.)

So what’s all this got to do with aliens and bacon? Well if aliens take the same stance—the choice not to kill sentient beings based on nothing else but the value that sentience confers—then perhaps we do stand a chance of a peaceful coexistence. But if aliens come with predacious intentions, aiming to harvest, experiment, extract, and/or exploit, there really is little we can do to stop them.

So hope and pray that, when our skies are darkened by the spectre of a flying saucer drifting through trembling clouds, you can smell the pungent aromas of Quorn and lentil burger emanating from the ship’s kitchen. Maybe that’s why they were called little green men all along?

O is for Ocean Acidification

By Jonathan Farrow from the Thoughtful Pharaoh

We all know that CO2 emissions are warming the planet.  Or at least, most of us do.  What often goes unreported is the effect of carbon dioxide on the worlds’ oceans.  A lot of the CO2  that we pump into the air makes its way to the water and is making it more and more difficult for shelled creatures like sea urchins, lobsters, and coral to survive.

Lobster
This is Bob the lobster. This is his “I’m sad because of the increased levels of anthropogenic carbon dioxide that are making my life harder” face.  Image by Pedrosanch

In order to understand why this happens, we need to go back to secondary school chemistry.

Don’t worry, I’ll make sure Jared doesn’t pick on you.

Jared
No Jared! No!     Image public domain

The first lesson we need to recall is about acids.  What is an acid?

Something that bubbles in a flask?  Image by Joe Sullivan
Something that bubbles in a flask? Image by Joe Sullivan

Acids are compounds that have free hydrogen ions floating around.  These hydrogen atoms are quite reactive, so it means the more free hydrogen you have floating around, the more reactive your compound. Acidity is usually measured in pH, which stands for the “power of hydrogen”.  pH is measured on a scale (creatively named the “pH scale”) that ranges from 0 to 14.

Compounds that get a 0 on the scale are exceedingly acidic, meaning they are made up of pretty much just free-floating Hydrogen ions. Compounds that rate 7 are perfectly neutral, like distilled water. Compounds on the other end, near 14, are called “basic” or “alkaline” and instead of having lots of hydrogen ions to give away, they have all sorts of space for hydrogen atoms.  This makes them reactive because they can strip hydrogen from things that don’t usually want to give it away (like Edward Norton’s hand in Fight Club).

The other confusing bit to remember is that the pH scale is logarithmic, meaning that each number you jump actually indicates a multiplication by 10. For example, something with pH 3 (like soda) is 100 times more acidic than something with pH 5 (like coffee).  This means if a large body of water (like the ocean) shifts by even a small pH number, the effect can be very large.

Image by OpenStaxCollege
Image by OpenStaxCollege

The second lesson we need to recall is about equilibrium.

In chemistry, everything tends towards balance. If you combine equally strong acids and bases, they will react together until the result has a pH that is in between.  You might also get a volcano-themed science fair demonstration.

When CO2 combines with water (H2O), they form carbonic acid (H2CO3).  The carbonic acid will break up (dissociate) into bicarbonate (HCO3) and a hydrogen ion (H+).  In a basic environment, the bicarbonate will dissociate further into carbonate (CO32-) and the result will be two hydrogen ions (2H+).

We can visualize this path with a chemical equation:

H2CO3  —-   H+ + HCO3–   —-   2H+ + CO32-

Where this path stops depends on the environment it is in.  In an acidic environment, the balance will tend towards the left, with more hydrogen bound up with the carbonate (because there is no space in the solution for more free hydrogen).  In a basic environment, the balance will tip to the right, releasing more hydrogen and freeing up the carbonate.

Currently, the pH of the ocean sits at about 8.1 (slightly alkaline).  Because of this, there is plenty of carbonate available for creepy-crawly-shellfish to use to build their homes.  Crustaceans and corals combine the free carbonate with calcium to form calcium carbonate (aka limestone, chalk, and Tums). They can’t use bicarbonate (HCO3) or carbonic acid (H2CO3) and find it hard to form anything at all in an acidic environment.

This means that as we add CO2 to the water, we create more carbonic acid and contribute to the acidity of the ocean, dropping its pH.  Not only does this make it hard for the little guys down there trying to make a living, but it also endangers the big chompers that eat the little guys.

The ultimate big chomper.  This is what happens when you jokingly search for
The ultimate big chomper. This is what happens when you jokingly search for “chomper” on wikimedia.

A recent review found that even under the most optimistic emissions scenario, the ocean’s pH is likely to drop to 7.95, affecting 7-12% of marine species that build shells. Under a high emissions scenario, the pH will go down to 7.8, affecting 21-32% of those species.

In order to keep track of the progress of this acidification, researchers from Exeter have proposed using satellites to monitor hard-to-reach bits of the ocean.

Regardless of the pace of the change, scientists agree one thing is certain: the oceans will become less hospitable for shell-builders.  The superficial impact of this for humans will be rising prices on shellfish, but there will be much deeper ramifications throughout marine ecosystems.

And I think we all know who is to blame.

Jared

Thanks Jared.

M is for (exo)Moons

By Jonathan Farrow of the Thoughtful Pharaoh

With this post, rising-ape.com is now caught up with my website, thoughfulpharaoh.  From now on, I will be posting articles simultaneously on both sites, on Wednesdays.

Thanks to everyone for following along and as always, if there is a topic you have in mind, don’t hesitate to leave a comment below.

And now for this week’s article: exomoons.

There are 8 planets in our Solar System (sorry Pluto).  Most of these planets have companions that follow them around, like obedient pets and criminal records.  The total count of these moons is 181.  We are all quite familiar with the big shiny one that orbits Earth (that may or may not be made of cheese), but what many people don’t know is the sheer number of other moons that exist in our Solar system.

Just like planets, these moons come in all different shapes and sizes.  S/2009 S1 is only 400m across and orbits in one of Saturn’s rings, making it the very smallest moon.  Ganymede, the solar system’s largest moon, measures in at about 5300km across, almost half the size of earth.

One of the biggest findings to come from the Kepler mission is that most of the stars in the galaxy have planets.  In other words, our solar system isn’t unique.  That means our Solar System probably isn’t the only whose planets have moons.  If our system, with 22 times more moons than planets, is any indication, there are a lot of moons to find.

This presents two immediate problems: firstly, why should we want to find them?  Secondly, how do we go about finding them?

Why find an exomoon?

The same thing that makes seawater rise and fall twice a day, tidal forces, can heat up a moon.  Tides are a result of the fact that the strength of the force of gravity is related to the distance between two objects.  On Earth, the water on the side close to the moon gets pulled out towards the moon stronger than the water on the other side, this creates bulges of water that move around as the earth spins: tides.

Tides stretch.  Image by Krishnavedala
Tides stretch. Image by Krishnavedala

The Earth is too small and our moon is too far away for much more than sea level change to happen, but Io, one of Jupiter’s moons, has over 400 active volcanoes caused by extreme tides from the gravity of its host planet Jupiter. In this case, it’s not just bulges of water that are created, but bulges in the crust of the moon itself.  This creates an immense amount of friction and heat. Europa, another moon of Jupiter, gets enough energy to keep a planet-wide ocean of water liquid under its icy crust.  Some people think Europa might be habitable, even though it is so far away from the Sun.

If there are moons here in our Solar System that can be habitable at Jupiter-like distances, there could be moons in other systems that orbit planets much closer, at Earth- or Mars-like distances.  Some people, like Rene Heller at McMaster University’s Origins Institute (a fine institution, if I do say so mystelf *full disclosure: I did my undergrad there*), think exomoons might be our best shot for finding habitable places in the galaxy simply because of their abundance relative to planets (remember, there are 22 times more moons in our system than planets).

How to find an exomoon

This is the tricky part.  It was hard enough finding exoplanets. Finding a transiting exoplanet is often compared to looking for the effect of a mosquito passing in front of a car’s headlight.  In that analogy, finding an exomoon would be like finding out how many legs it has.  No easy task.

It’s not impossible, though.  Moons do have effects on their planets and if we look carefully enough, we can find them.

One way to find exomoons in transit data takes advantage of the fact that, viewed edge-on, a moon will appear more often at the edges of its orbit.

ExoMoonTransit
Image by Rene Heller

If you capture many transits over time, you can begin to see these wingtips in the transit data.

Image by Rene Heller
Image by Rene Heller

The grayscale bar in the image above represents the average effect of a moon orbiting a planet.  What astronomers can look for in the transit data is a preliminary dip (1) that starts off severe then levels off, followed by the regular planetary transit (2), followed by another characteristic dip (3) as the other wingtip passes in front of the star.

This method only works if you have a lot of data, but luckily Kepler was operational for four years and gathered just the right kind of data.

So now the search will begin.  Who will find the first exomoon?  And what if it turns out to be “no moon” at all?

An artist's impresison of a view from an exomoon with a triple star system.  Far out, dude.  Image by NASA/JPL-Caltech
An artist’s impresison of a view from an exomoon with a triple star system. Far out, dude. Image by NASA/JPL-Caltech