bubble observations

This narrative describes our first task.

Walking into a first day of a science class, one of the proclamations that we’re conditioned to hear is about the power of the “scientific method.” There are plenty of first chapters of textbooks that devote themselves to describing a bit about what science is for, how it’s both an extension of things we naturally do, and a sharp contrast to other ways of knowing. And then there’s that scientific method. Each text is a little different on this point, but the essence is that we root out truth by testing our explanations against what we actually observe.

But I think we need to start somewhere else, back just a bit. I’m not sure that we really always agree on what it means to “observe.” And, it’s probably good to actually put this into practice. Observation is like any other skill.

For me, a sensible introduction to physical science is to begin with soap bubbles. This could be with a sink full of water and some dish detergent, or it could be some canister of stuff that you have left over from a summer birthday party. There are a few recipes that I like, but the basics of any of them include about 12 parts water and one part simple dish detergent. Put a wand, a straw, or even the end of a pipe or funnel into the solution so that a film stretches across one end, and then blow through the other.

What do you observe?

Get out your science journal. This could be a simple composition notebook, lined or unlined in any fashion you like. For me, the important part is that it’s a notebook that accompanies you and records ideas, observations, questions, and pursuits that may or may not lead to anything else. It’s not necessary that it’s pristine or even particularly well organized. You can display your edited genius in some other way, but this should be something that’s flooded with mistakes, ramblings, and snippets of ideas. It’s your blueprint of potential.

Find a page to start and document bubble observations. Having a partner in this pursuit is useful, not only because one person could be blowing the bubbles and the other could observe something closely, but because one person’s observation can lead to another. That said, there’s something about just sitting with an observation all to yourself. It’s up to you. (Often I’d have you start this in class, with a partner; and then you’d head home armed with your notebook and your bubbles to do more observations yourself.)

One of my favorite photos is this one of a girl playing with a giant soap bubble.

What do you observe?
What do you observe?

It’s a good example of the many things that we could find in a soap bubble if we look closely. First, there’s the bubble itself, stuck to her hands. There are colors that are rainbow-ish, but not really the same colors that you see in a rainbow. Then, looking a little more closely, there’s a reflection of the sun at the top of the bubble, as well as another at the bottom of the bubble. There’s a big drop of bubble goo starting to form at the bottom, too. And there are hands — not just those holding the bubble, but reflected images of those hands at different places. Look some more and you’ll see that the photographer is in this image as well, reflected back from the front surface, his camera and hand towards the center, his legs and feet at the bottom. Each time I look at this image, I see something new.

Your first observations might be about how the bubbles form, how they fall or drift, what they do when they hit the ground, how they interact with one another, and on and on.

Keep observing. There’s no rush, and there’s plenty to see.

_____

The following essay, written by Samuel Scudder, was about his first experience in graduate school. He showed up to essentially begin his apprenticeship as a research scientist, ready to study insects. His professor greets Scudder and tasks the student with observing, of all things, a dead fish.

The Student, the Fish, and Agassiz,” by Samuel Scudder (1879).

Give this a read and consider what’s happening to Scudder and how he’s learning to observe. Go back to your own bubbles, again, and observe as Scudder might recommend to an apprentice scientist.

Go ahead, I’ll wait.

_____

What kinds of things do you observe with the bubbles now that you didn’t see before?

In general, we see more details that might seem more elaborate; we might take a pencil (like Scudder did) to start to observe through writing and drawing; and it might occur to you for the first time to note that the bubbles are round, just like fishes are symmetrical.

It should be no surprise that Scudder wasn’t the first nor the last person to observe a fish. Here’s another account:

The Fish”, by Billy Collins (as published in the New York Times, along with some recipes)

Billy Collins is a notable poet, holding the position of U.S. Poet Laureate from 2001 – 2003. His observation of a fish is quite different — and not just because he’s at a restaurant in Pittsburg, although that’s clearly part of it.

Consider the perspective of a poet. Go back to your bubbles and observe again, still using that notebook, but now looking through the lens of a poet or perhaps even another artist. You don’t need to write your own poems (though no one is stopping you). Just observe from this new perspective.

Now, what do you see?

_____

The point of this exercise is two-fold:

First, observation is something that we take for granted as a practice and a skill. It’s at the very heart of what science does, where it starts. We don’t come up with questions or investigations or models or anything else until we’ve experienced phenomena in some way. Sometimes, the experience is in the mind’s eye, constructed from other things that we know, like with something as exotic as a black hole. Most of the time, though, I suspect that we start with an observation that’s very simple, seen but unobserved until we take the time to really delve into it.

Second, “observation” isn’t an action without context. The observations are different and differently directed if we look at something as a scientist rather than as a poet. As a scientist, we look for patterns that lead to an understanding of how things are put together, why they might move the way they do, how they function. As poets, we probably associate other meanings with what we see. Empathy and metaphors, statements about the human condition and how we can relate these to one another — these are all outside of scientific reach, but they’re still valuable in their own way and with their own purpose. The work of the scientist might impact the work of the poet (or the painter or the philosopher or the writer or anyone else), but it’s important to be clear about which of these lenses we’re wearing. Throughout this course, we’ll refine the lens we use as scientists, but this doesn’t mean the other lenses are less valuable. They just have different goals.

 

Astrophotography

Note: This is just a quick tutorial on astrophotography. For other astronomy resources, take a look at this collection I’ve been compiling. (And let me know if there’s something more that you are looking for.)

Disclaimer: I’m not an astrophotography expert. I just get the basic idea and I like to mess around with this. I think that astrophotography is easier than working a telescope and in many ways it’s more immediately rewarding. It also gives you something fun to play around with on even modest cameras. As long as you can keep a shutter open for a few seconds, you can do astrophotography.

You can read my basic description below. In addition:

  • You’re welcome to pull up this Astrophotography Presentation that I use for workshops.
  • Here’s a collection of photos taken by people at one of these workshops.
  • There are plenty of other tutorials like this that are more detailed than what I’m providing here.
  • Many of us carry phones around not for calling people but for taking pictures. They aren’t ideal for astrophotography because they have small sensors and apertures, but there are some apps that can add multiple exposures together. Here’s one example that I’d like to play with more.

Here’s the basic idea. The stars are very dim from our perspective, since we’re really far away from them and their light is spreading out and sharing that energy all over space, limiting us to only a small fraction of that. In addition, the amount of light collected by your pupils is really small, both because the opening collecting the light is really narrow and because your eye sensors are refreshing what they’re detecting several times per second. Also, your detection system, the retina with its cones and rods, has a limited sensitivity. With a camera, you can adjust these factors. The display on my camera looks something like this for a “normal” photo:

Exposure, Aperture, and ISO

And, it would look something like this for astrophotography:

astrophotometering

There are adjustments that can be made for the amount of time that the shutter stays open, and for stars I generally want to adjust this to something like 5 seconds to start, depending on the camera and the conditions. Most of the time that you take a photo in daylight, the shutter stays open for a fraction of a second. Also, I should open up the aperture as wide as possible in most cases. In camera-speak, this means you should make the f-stop be a number that is as small as possible. And, I probably want to play with the sensitivity of the camera’s detector, what’s known as the ISO. (Back in the old days, we used film that we’d say was a certain “speed,” but that was really a measure of the sensitivity of the chemicals in the film.) This is tricky because as you increase the sensitivity, you also allow for a grainier and perhaps even noisy looking background, which is exactly the opposite of what you want in astrophotography. Also, the measure of ISO is something that seems to change with each generation of cameras, and using really high sensitivities on a camera made in the last couple of years would have been unheard of just a few years previous. So, start with something and see how it turns out. For me, I have a 35mm lens (fixed focal length) that I can open up to f-1.8, and to start I’ll open the shutter for 5 seconds and use an ISO of 1600. (I use a Nikon D5300, in case that’s relevant to you.) After that I’ll just play around. If there’s a lot of light pollution, this will be way too long and the photo will be washed out. If I have dark skies, this will show wide variety of stars with a still dark background.

There are a few other important pieces. First, if you’re going to leave the shutter open for several seconds, you need the camera to be absolutely still. A sturdy tripod is important for this … or so everyone says. Honestly, I’ve used a bag of marshmallows propped on a rock with a smaller camera positioned just so, but on the other hand I’m not getting award winning images with that technique (unless it’s in a special marshmallow-propped category). Use what you have and see how it goes. But, probably the most violent time for the camera is when you’re pushing the button to take the photo. So, especially if you don’t have a good tripod, try a setting that makes the camera trip the shutter a few seconds after you’ve pushed the button, or perhaps use some kind of remote shutter button. (More and more often, there are ways to connect your phone to a camera over bluetooth or wifi.) You’ll find these options on most cameras under some menu that gives you choices for delayed shots like this, as well as for rapid-fire exposures. Finally, you need to focus on the stars. It seems like this should be easy, but I see mixed results with every camera I’ve played with. Stars are practically an infinite distance away, so you should set your focus, manually, to infinity. (Autofocus probably won’t work because there’s so little for the camera to “see.”) This always seems to be just a touch off for me, so my suggestion is to play around with it. Most of the time I use the viewfinder while pointing at a distant object on the horizon and get it as sharply focused as possible and then just leave the focus there. Stars that are in focus will look like sharp points. They shouldn’t have any significant diameter to them (unless they’re planets). Depending on your camera, you may find other focusing strategies as well. Some cameras have a digital control of the manual focus, and you can actually select “infinity” on the focus control screen.

I’ve compiled a few modest photos with a compact camera, but here’s one that I think is a good example of what you can do with a simple point-and-shoot camera (before I had a DSLR):bigdipperfield

This is one of those photos that was taken from the hood of my car with a table-top tripod. With this photo, you can clearly make out the Big Dipper (centered, bottom third of the frame) and the double star in the handle. Above that you can make out the entirety of the Little Dipper, something that’s hard to do with the naked eye except with the darkest skies. And, at the bottom of the photo you can see a streak of fire-like light. This is actually the tail lights of a car going by, which gives you a sense of the exposure time for this photo.

Here’s a very similar field of view, but taken from a darker location in the Uintas. If your monitor if bright enough, you can make out the outline of trees that block the stars behind.

And finally, here’s a photo taken during a workshop with local teachers. This tripod was set right here on the observatory roof of Tracy Hall Science Center at Weber State. Looking north, we were able to pick up Cassiopeia, a streak from a satellite, countless other stars, and even the Andromeda Galaxy. The light from the latter is 2 million years old! (You can find a full resolution file in the original gallery.)

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