Is it a Theory or is it a Theory?

It’s really too bad the word theory has two very different meanings. To a scientist it means one thing to a non-scientist something vastly different.

The non-science meaning, according to old Merriam Webster, is “abstract thought, Speculation”. To the scientist it means something formed from testing a number of hypotheses (what would happen if I did this?) investigating a happening in nature.

For instance, the Theory of Gravity. Scientists over the years have tested a number of what ifs (hypotheses) relating to gravity, like what if I drop these two cannon balls of different weights off a building? Or does this mathematical formula predict the motion of the planets? Or does a lead ball and a feather fall at the same velocity in a vacuum? After enough what ifs are proven to be true a theory begins to take shape to describe the thing being investigated, whether it is the Theory of Gravity, The Germ Theory of Disease, Einstein’s Theory of Relativity or The Theory of Evolution.

Scientists do not assign the title ‘Theory’ casually. To achieve this high level of trust it must be rigorously and ruthlessly tested, again and again. This does not mean that scientific theories are never rejected. Some have been in the past as we have come to better understand how things are. For instance, the Phlogiston Theory of Combustion which tried to explain burning as the release of a substance called Phlogiston and its absorption by air. The argument was that burning stopped in a closed container because the air inside the container could only absorb so much Phlogiston and when it had absorbed all it could, burning ceased. Other hypotheses tested the role of oxygen in burning eventually proving the Phlogiston Theory false.

Scientific theories are also modified as new hypotheses are tested and new information is discovered.

However, the Theory of Gravity, Theory of Relativity, Germ Theory and Theory of Evolution have survived many, many years of brutal scientific challenge and while they may be modified they will not be disproven.

Why do we have a moon?

If you asked one of my second grade buddies that question they might say, ‘because’.

That answer usually works pretty well, but I thought if I poked around some I could do a little better.

I found four ‘becauses’.

An early theory explained the moon by saying it formed from the same gas cloud from which the Earth and other planets formed. This explanation doesn’t fly because the moon contains very little iron. The Earth has a lot, mostly at its molten core. If the moon formed out of the same stuff as the Earth, the moon ought to have more iron.

A second theory explained away the Moon’s small amount of iron by suggesting the Moon formed somewhere else, where there wasn’t much of that pesky iron, and captured by the Earth’s gravitation as it swung by. This one didn’t work out either. When samples of the moon were brought back by Apollo astronauts and analyzed, it was found that they had a chemical composition almost identical to Earth’s making it unlikely that it came from somewhere else.

A third idea tried to explain away the Moon’s ‘iron deficiency anemia’ by suggesting the early Earth spun so fast that some of its surface was flung off and went into orbit. The hole it left was the Pacific Ocean basin. Since most of the Earth’s iron is at its center, the flung off material would not have a lot of iron in it. Nice try, but when they crunched the numbers relating to the Moon’s orbit, they found the math didn’t work out.

The latest theory is that a chunk of debris, leftover from the formation of the Solar System, slammed into the Earth and knocked a large amount of the iron poor crust loose. Scientists estimate that the piece that hit us was a third to half the size of the Earth. The material blasted loose formed a ring around the Earth which clumped together to form the moon. This is the currently accepted theory.

It’s interesting that even after decades of head-scratching, scientists are still not really sure how the moon came to be.

Maybe ‘because’ isn’t such a bad answer after all.

Are we really descended from Apes?

The quick answer is NO! Apes are more like cousins than ancestors. At some point in deep time we went one way, they went another. We share the same common ancestor, but they are not our ancestors.

As a matter of fact, all life on Earth shares a common ancestor whether you’re human, an ape, carrot, broccoli (echhh), fish, bird, oak tree—you get the idea. The common ancestor of all life on Earth was a single celled organism that lived billions of years ago.

How can we be related to a broccoli? That’s a plant not an animal.

All life on Earth shares the same cellular chemistry, cell structure, DNA and is either a single cell or made up of cells working together. What makes sense is that the problem of deriving energy from food, a means of passing on heredity, reproducing and all the necessary structures of a cell were solved by single-celled organisms, probably around two and a half billion years ago.

Some of their descendants branched off to become plants or animals, branching and branching through billions of years of evolution to populate the Earth with all the millions and millions of species living or extinct. The odds that millions of different living things evolved the same chemistry, hereditary material, and cellular structure independently are so beyond astronomical as to be non-existent. That means we are related to every living thing, even broccoli, because all living things descended from those single celled ancestors.

What about our supposed Ape ancestor? Well, we branched off from the nearest ancestor common to both of us around five to seven million years ago.

You know, if you think about it---we do kinda look alike.

Is it a meteor or a meteorite? And where do they come from?

A meteor is a small, solid object that burns up upon entering the Earth’s atmosphere. The bright streak it makes is commonly called a shooting star. If it makes it to the ground it’s called a meteorite. I don’t think that definition includes objects lost from the Space Station, like a wrench or tool bag.

Some meteors are the remnants of the early formation of the Solar System, bits and pieces that didn’t get incorporated into planets or moons. Since they burn up in our atmosphere or land on the ground you could say they are now being incorporated.

Comets, which are kind of like big dirty snowballs, since they are made up of ice and some dust, are the source of a few meteors. Comets orbit the sun out beyond the orbit of Pluto, which used to be our most distant planet, but is now called a planetoid---a really long story. Sometimes the gravity of big planets like Jupiter will disturb a comet’s orbit and it will pass close enough to the sun to warm up and shed a trail of debris. When the orbit of the Earth passes through this trail we get a meteor shower.

Most meteors come from the asteroid belt, that bunch of stuff making a ring of debris around the sun between the orbits of Mars and Jupiter. Some are of interstellar origin, from outside our solar system, or even pieces of our moon and Mars, dislodged by an asteroid impact.

Most meteors are made of stony material. A few per cent are mostly iron and nickel. The majority of meteors range in size from specks of dust to sand-grains. Luckily only a rare few are much larger, such as the six miles in diameter meteor that gouged out the huge crater in Arizona. That left a mark, a crater three-quarters of a mile in diameter and six hundred feet deep.

Why doesn't the International Space Station fall back to Earth?

Funny you should ask, I was wondering the same thing, so I did a little research and this is what I learned.

The answer is it’s falling all the time. Huh, what??

Here’s what’s going on. Let’s say we have a cannon and we can put any amount of gunpowder in it and shoot a cannon ball as fast as we want. We take it to the top of an impossibly high mountain, to get away from the drag of the atmosphere, make sure it’s level and fire it. There are two forces acting on the cannon ball, the straight-out force given to it by the cannon and the downward force of gravity. The result of these two forces is a downward curve. If we use more powder and shoot the ball faster it will travel farther before hitting the ground. If we fired the cannon ball at the right velocity, it wouldn’t hit the ground at all because the result of its forward motion and downward motion is a curve that matches the curve of the Earth. Our cannon ball would fall around and around the Earth because the ground is falling away at the same rate as it is falling, so it just keeps missing the ground.

The International Space Station’s velocity is about 17,000 miles per hour at a height of about 200 miles. At that speed and altitude its path or orbit is a curve that matches the curve of the Earth, so it is falling and falling and falling around the Earth and so is everybody and everything inside, even those M&M’s they try to catch in their mouths.

Ant Plant

We all know that insects eat plants and some plants return the favor and eat them, like the Venus Fly Trap. Plants eat insects (actually absorb) in order to get nutrients that may be hard to come by where they live. But, there is a plant that gets extra nutrients by simply providing a home for insects --- in this case ants. It is known commonly as the Ant Plant (Dischidia pectinoides). This native of Western Asia and the Western Pacific, for instance the Philippines, grows not in the ground, but on tree trunks and limbs as do many orchids. Botanists call them epiphytes, which means in Greek, epi-upon, phyte-plant.

The home the Ant Plant provides is a bladder-like structure that is really a modified leaf (See Photo). The ants enter and leave through a small hole at the base of the bladder where it attaches to the stem. In return for a home, the ant provides the plant with the carbon dioxide plants use to make food, using sunlight, through a process known as photosynthesis (Greek again), photo-light, synthesis placing within.

It also gets nutrients from the detritus (a fancy name for ant poop and the other good stuff the ants track in) the ants bring into their bladder home. These nutritious tid-bits are absorbed through the walls of the bladder as is the carbon dioxide exhaled by the ants. The ants probably benefit somewhat from the oxygen exhaled by the plant and no doubt by the shelter provided. Organisms benefit when they don’t have to expend much energy to gain something they need for their survival. It gives them a nice advantage.

Now why in the world did this amazing plant evolve such a unique way of earning extra income? Kinda like renting out a spare room. Maybe it’s not extra. Maybe in a habitat that is crowded with plants there is a lot of competition for carbon dioxide, all the other plants are sucking it up too as well as nutrients. Maybe to make ends meet, the Ant Plant really needs that extra income provided by its renters-- the ants.

Any other ideas as to why the Ant Plant goes to all this trouble?

How Does Soap Work, Anyway?

Soap’s been around a long time, at least six thousand years, but how does it get that spot of gravy off your favorite shirt?

A molecule of soap is a long chain of carbon and hydrogen atoms with some oxygen atoms tacked on at one end. The end with the carbon and oxygen likes to attach to water molecules and the other end, which is just hydrogen and carbon, likes to attach itself to oils. This oil the carbon-hydrogen end likes so much is what can make dirt mixed with it so hard to remove because the oil likes to stick to the fibers of the material in your shirt.

When you dissolve soap in water the oil loving ends attach to the oil in the gravy stain and the water loving end (the end with the oxygen), attaches to a water molecule. Usually what happens is that a bunch of soap molecules surround the oil to form a glob of soap-oil-dirt with the dirt-oil in the middle of the glob and the water loving ends of the soap molecules sticking out hanging on to the water. Now when you stir things up, like when you slop your shirt around in the soapy water, the soap and oil glob is lifted from the shirt and suspended in the wash water.

When you rinse your shirt, the soap-oil-water combo is washed away and hopefully you have a clean shirt and no one will ever know you dripped gravy on it.

Is Global Warming the only problem with too much of a greenhouse gas like carbon dioxide?

That’s bad enough, but there is more bad news.

The large amount of carbon dioxide produced by our activities is also finding its way into the world’s oceans as an acid—carbonic acid. That’s pretty much the same stuff as in sodas where carbon dioxide is used to make them fizzy. There’s not enough dissolving in the ocean to make it fizzy, but enough to begin to make it more acid. (What I intended to say is carbon dioxide makes sodas fizzy, not carbonic acid-I need to proof read better!)

That’s bad news for small critters like plankton, coral and other organisms that have shells which they make out of a substance called calcium carbonate-we all know it as the chemical that makes up limestone and eggshells. Why? Because as the ocean becomes more acid, it is harder for them use this compound to make their shells and without shells it is hard if not impossible for them to survive.

What sort of marine organisms? Clams, oysters and corals are probably the ones we all recognize right off, but those small plankton we mentioned earlier are really important too because they are the base of the food chain for many animals. Small fish feed on them, which in turn are fed on by dolphins, some whales, penguins, birds, humans, and the like. The point is that as the ocean continues to grow more acidic, many of the sea’s creatures will simply not be able to survive.

That’s the other worry about an excess of carbon dioxide.

Why Does the Sun Have Spots?

The simple answer is that planet sized areas on the sun’s surface are cooler than the rest of the surface and appear darker. Taken away from the brighter background they are still really bright. It’s simply a matter of comparison.

Why they are cooler is a little more complicated. If the simple answer is all you want, great. If not, please read on.

It has to do with stuff called plasma and a thing called magnetism.

Plasma is an atom—in the sun’s case usually an atom of hydrogen or helium-- that has lost electrons because the sun’s intense temperature tears them loose. The loss of electrons leaves the atom with an electrical charge. This is because an electron has a negative charge, so when one or more electrons are torn from an atom the atom is left more positive. The sun’s magnetic field can now influence it. Here’s where the sunspots come in.

In some places the sun’s magnetic field gets twisted--scientists are still trying to figure that one out--and pokes out through the surface, called the photosphere, and arch back in. Under the surface of the sun is an area, called the convection zone, where the hot plasma heated by the sun’s core rises to the surface--like water boiling in a pot. The place where the magnetic field comes out and the place where it in goes back in slows the plasma’s rise to the surface. These places are cooler than adjacent areas where the plasma rises to the surface uninhibited.

The cooler spots look darker because they are cooler and give off less light.

And that is why the sun has spots.

Why is the Grass Green?

One of the kids at the elementary school where I volunteer asked me why grass is green.

Good question for a seven year old. I think I was at least sixteen before I thought to wonder about that.

Anyway, the answer has to do with pigments. Pigments are any substance that absorbs light. We have all seen rainbows so we know that sunlight is made up of many colors. The ones we can see run from red to violet with all the other visible light between those two. The frequency of light a pigment absorbs determines its color. What’s a bit confusing is that the color of the pigment is actually the color of light it doesn’t absorb. If the pigment looks red, then it has absorbed all the colors but red, which it reflects.

Plants have pigments which don’t absorb much green, which they reflect. So plants, including grass, look green.

Global Warming and Sea Ice

A friend of mine asked me why scientists are so worried about melting of sea ice at or near the poles.


Well, aside from the fact that it's melting is a pretty good indication that the planet is warming, it’s scary because of a thing called ‘positive feedback’, which despite sounding so upbeat is in the case of global warming a potential catastrophe.


An example of Positive Feedback is when an event such as warming of the oceans creates more warming of the oceans. So, how does sea ice come into this? We all know that a dark object absorbs more heat from the sun than a white one does. As the sea warms and melts more white sea ice there is less ice to reflect heat and more dark sea surface to absorb it, the sea warms melting more ice exposing more sea surface to absorb heat, etc. The dangerous part is that this vicious cycle increases in speed until it is at a ‘tipping point’ beyond which there is no going back.


And that’s why scientists are worried.

I Was Busy

I had promised myself to do at least one new entry per week, but got blindsided by an unexpected brain surgery, of all things.

Somehow I thought that having diabetes for 35 years was enough. Guess not.

Anyway, I'm back and now somewhat knowledgable regarding benign meningiomas; if anybody has any questions.

Lyle

How Lungs Work

Imagine our lungs as a very thin sheet of tissue about the size of a tennis court (about 400 square feet) surrounded by air and connected to your bloodstream.

Now imagine your heart pumping blood to, from and through this rather large sheet of tissue. One side of your heart receives blood carrying carbon dioxide from the cells of your body and the other side of your heart receives blood loaded with oxygen collected by passing it through this large tissue sheet. The blood loaded with carbon dioxide is sent by your heart through this sheet of tissue where the carbon dioxide is released from your blood through the very thin tissue walls by a process called diffusion. The same process that causes perfume to spread from where there is a high concentration of perfume (like when you drop and break a bottle) to the rest of the room where there wasn't any to start with. Gases like carbon dioxide and oxygen work the same way.

OK, now we’ve gotten rid of the carbon dioxide, but now we need to get that oxygen our body needs.
Blood cells contain a molecule called hemoglobin. This molecule is what gives our blood its red color. Hemoglobin loves to grab onto the oxygen molecules diffusing (remember the perfume?) through this thin, flat really big piece of tissue from the surrounding air. The ‘oxygenated’ blood is returned to your heart and pumped throughout your body to your cells. The hemoglobin releases the oxygen to the cells which 'burn’ it, to provide the energy for all the things our bodies have to do, and in the process convert it to carbon dioxide which our amazing plumbing system returns to our large sheet of tissue to begin the process all over again.

Now it would be a little difficult to try and drag this tennis court sized tissue around all day, so the body does something very clever. It achieves the high surface area it needs, to do all this diffusion, by dividing it into about three hundred million tiny, hollow sacs called alveoli (little balloon-like sacs the size of grains of salt) which line the walls of two larger sacs called lungs. Although the surface area of each of these tiny sacs is small, with millions of them you can get the same surface area as our flat sheet of tissue. The tiny sacs are lined with really tiny blood vessels called capillaries that allow the exchange of the carbon dioxide and oxygen.

Air enters our lungs by way of what we commonly refer to as our windpipe which branches into ever tinier and tinier tubes eventually branching into tubes tiny enough to lead into the tiny air sacs, the alveoli. When you exhale the alveoli deflate expelling carbon dioxide laden air in to the lungs and when you inhale they inflate taking in oxygen rich air. This is what we call breathing.

But you probably already guessed that.