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Ellen's Communication Diary Day 1 2 3

Day One

Challenge: To make a space pen and ink. We’ll test it by lying on our backs and writing upside down for a long time.

This is actually a tougher test than writing in space, because in space there is zero gravity - no force (pushes or pulls) acting on the ink. When writing upside down on Earth, gravity pulling down on the ink works in exactly the opposite direction as we want the ink to flow, so our space pen not only has to work in space, it has to be designed to overcome Earth’s gravitational force acting on the ink.

Strategy: Mike works on the pen design. I hit the road to find plants that will give rich, permanent ink colours.

We’ve made inks and dyes in other Rough Science challenges, but never in this region, nor in the desert. Thus, it is, once again, a legitimate challenge. The issues are:

Finding appropriate plants. It is not as if there is a map with plants marked on it. I have to go to areas (habitats) where the specific plants I want are likely to grow well and then hunt around. If what I’m looking for isn’t there, I go to another location that with similar environmental conditions and look there. I always keep my eyes open for species I may stumble over that I hadn’t considered but would work well.

Extracting the chemical components of the plants that have colour and will “stain” paper. This usually involves boiling plants in water for anything from 30 minutes to several hours.

Concentrating the ink. This is tougher than one would think. Yes, boiling off water is the starting point, but the plant components that work as inks are sometimes so dilute in the plant that tons of plant material is needed, so boiling takes a long, long time. Dyes don’t have to be as concentrated, nor do they have to be thickened, to work reasonably well, so many plants which give a nice colour as a dye just can’t be practically concentrated as an ink. Inks are tougher to make.

Thickening the ink without diluting the colour such that it flows onto the paper without running all over the paper or leaking out of the pen. Yet, the ink still has to flow through the pen. This is a real give and take.

Inks
The immediate plants that come to mind are seablight, also called inkweed, and sagebrush. Inkweed was used by Native Americans to dye basketry materials and hair black. I am counting on the fact that detailed basketry painting and dyeing, as well as hair dying, require concentrated colour. These uses suggest that I should be able to make a decent ink out of inkweed. Inkweed is found in dry areas with saline (salty) soils. It is edible, but tastes quite salty, thus its other common name of seablight. The part of the plant above ground is boiled to make ink. The colour is strongest when the plant is in bud or flowering.

Sagebrush is a back-up as an ink. It was used by Native Americans as a yellow-green dye for cloth. This means Mike and I will probably have a heck of a time concentrating it as an ink. Plus yellow-green isn’t very dark in the first place. There just aren’t many ink choices around here. As I haven’t worked with inkweed before, I’m not willing put all my eggs in one basket. We’ll try the sagebrush, too. Sagebrush is typically found between 5,000 and 9,000 feet above sea level in dry areas. Its scientific name is Artemesia tridentata. If you look at its leaves closely you can see that they have “three teeth” (tri=three, dentate=teeth) at their tips. Also, sagebrush is not related to sage, which makes things quite confusing. Sages are in the mint family. Sagebrush, on the other hand, is in the daisy family. This is one of the reasons common names are sometimes very misleading!

Thickeners
The obvious thickener is apricot mallow, also called desert mallow. I saw it all over the place last week as it was in flower, so it should be easy to spot with its bright orange flowers that are the size of US quarters.

Other options for thickeners include grinding up the seeds of plants that Native American used to make mush, which is basically oatmeal or cream of wheat out of plants that aren’t oats or wheat. An obvious candidate is any one of the local buckwheats, but I’m pretty sure they are still in flower. It will be a couple of weeks before the flowers, if they are pollinated, develop into fruits with seeds—and I only have days, not weeks, to come up with a reasonably thick ink.

Results so far
As expected, inkweed was readily available in this dry, salty region. For sagebrush, I’ll have to go up higher in the hills. Apricot mallow is proving illusive. It has stopped flowering, and based on the one puny plant I found, it loses most of its leaves once its flowered. I’ll have to hunt for this plant based on its stem architecture and see how I do. It’s basically like looking for lost keys based on their shape.

Mike, in the meantime, has made two brilliant prototypes of pens. Both are way to big to be practical, but the science behind them is fab. One is a capillary pen that won’t even require thickened ink. The other is a version of the ball point pen. Who would have ever thought we’d make a ball point pen on Rough Science. Cool!

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Ellen McCallie
Scientist Diaries

Will the Rough Scientists be able to get their message across? Read what they communicated through their diaries:

Iain
Jonathan
Kathy
Mike