Mongolia+
Dear Members,
You may remember that, in my last missive, I indicated that I was off to Mongolia with my son (his graduation present).
Well, 20,000 miles of international and domestic air travel later, I am back in a rather wet Cleveland Heights: no mis-haps, all flight connections made (just!), no dodgy tummies and a wonderful time had. You may ask: Why so far? Well, I needed to pick Harry up in London. Instead of a reasonable 6k miles or so via Chicago and Seoul to Ulaan Baatar, it was New York, London, Istanbul and then Ulaan Baatar at a little over 9k miles. But, Oh!, does it make a difference splashing out and going business class. I had hoped to be able to visit the Oyu Tolgoi (Оюутолгой) copper mine (it translates to Turquoise Hill ) down in the south of the country. Sadly, though, despite many pleas to the mine owners, I was unsuccessful. (Admittedly, I started on my persuasion efforts somewhat late: with such an operation you actually do need to provide a great deal of lead time: I didn’t.)
In a way, however, you don’t really have to go underground to get some idea of the mineral (and metals) abundance that surrounds you in parts of Mongolia—especially in some of the hills an mountains. I was reminded a little of Wren’s epitaph in St. Paul’s Cathedral, Si monumentum requiris circumspice (If you seek his monument, look around). Looking around me, many times I lamented that I was not a geologist! The greens of copper, the reds of iron, the blacks of basalt … I could go on, but I wouldn’t know what I was talking about. It was one of the many times I wished I was something other than a somewhat fatigued and burned out “money man”. But, there you go. That said, my quiz for knowledgeable members is: Whose abandoned wolframite mine is this? (We passed it on the hills above, I believe it was, the Khovd River (Ховд гол), two hours in a four-wheel drive Toyota Landcruiser, west of the town of Ölgii (Өлгий )—predominantly Kazakh—as we were headed towards the incredible Altai Mountains (Алтайтаулары or التاي تاۋلارى in Kazakh.)
It had only recently, a couple of years, been abandoned. And, when you see the whole scene, you have to wonder just how any ore could be mined profitably therefrom: its location was miles from anywhere and metalled roads were there none! Answers on a postcard to the MMTA, please.
Wolframite Mine on Khovd River (Ховд гол)—from a Moving Car!
Wolframite Mine on Khovd River (Ховд гол) Close Up—from Moving Car!
And, before turning to things more metals- and space-oriented, I thought you might be amused by this snap of some sand in the Gobi Desert. It came as somewhat of a surprise to learn that the desert is not all sand. And that across much of its rocky extent the green tufts sticking up from the dirt were wild chives! Yep, pretty strange. One local joke is that you don’t have to add herbs to the mutton when you cook it.
Khongoryn Els (Хонгорын элс)
Materials in Space
In the past several missives about metals used in space, I have looked at some specific metals, e.g. beryllium and gallium. I think it is probably worthwhile, now, to take a step back and look, in more general terms, at just what kinds of challenges these metals need to meet (successfully) when used “in space”.
As we saw, beryllium is light and strong and gallium solar cells are durable (in particular, resistant to gamma radiation), highly efficient (amongst other things, they have high spectral coverage) and lightweight. The environment in space is really no “balmy summer’s day”. To describe it as hostile (apologies for the anthropomorphism) would be an understatement: it is merciless. As NASA describes it: “Hardware exposed to space must withstand all aspects of the space environment. This includes vacuum, thermal cycling, charged particle radiation, ultraviolet radiation, and in some environments, plasma effects and atomic oxygen.”1
In addition, there’s the small matter of micrometeoroids and space debris particles which may impact at high velocities: even something tiny travelling at a small percent-age of c can be pretty destructive . To put some of these aspects in context, see the table below for a brief summary of what they can result in:
Cause |
Effect |
| Vacuum |
Outgassing: “ … which in turn affects any spacecraft component with a line-of-sight to the emitting material.” |
| Thermal Cycing |
“ … cracking, crazing, delamination, and other mechanical problems, particularly in assemblies where there is mismatch in the coefficient of thermal expansion.”
|
|
Charged Particle and Ultraviolet Radiation
|
“ … cross-linking (hardening) and chain scission (weakening) of polymers, darkening and color center formation in windows and optics, and single event upsets in electronics.” |
| Plasma Effects |
“ … contributes to the build-up of surface charge, especially in higher voltage systems. This surface charge can damage electronics, produce single-event upsets (SEU), trigger arcs in solar arrays or power systems, and cause dielectric breakdown of structure of surface coatings.” |
| Atomic Oxygen (AO) | “AO oxidizes metals, especially silver and osmium. AO reacts strongly with any material containing carbon, nitrogen, sulfur, and hydrogen bonds of 5 eV bond energy or less, meaning that most polymers react and erode away. Polymers containing fluorine, such as Teflon, react synergistically, where the reactivity to AO increases with longer exposure to ultraviolet radiation. [2] Some materials, such as ceramic coatings, can be bleached by exposure to AO.” |
And that’s just for “starters” and, just the materials for spacecraft!
There are also those materials for: launch vehicle structures; exploration systems; solid rocket engines; liquid propulsion systems; in-space propulsion; and power systems in space exploration. Some will be the same some will not. As must now be obvious, when it comes to the environment of space, one size does not fit all. Over the next couple of months, we’ll look at which materials, in particular metals, are up to meeting these pretty stiff challenges.
While I am off again (to Europe this time) at the end of this week for a couple of weeks, I shall resume my missives in July and continue with my “Space Saga”. In the meantime, though, from a wet Cleveland Heights, Ohio, as always I remain
Yours
Tom
June 2024
©2024 Tom Butcher
Tom Butcher, formerly Director of ESG there, is now a Marketing Advisor at Van Eck Associates Corporation (“VanEck”).
The views and opinions expressed herein are the personal views of Tom Butcher are not presented by or associated with VanEck or its affiliated entities Please note that VanEck may offer investments products that invest in the asset class (es) or securities mentioned herein. This is not an offer to buy or sell, or a recommendation to buy or sell any of the securi-ties/financial instruments mentioned herein.
1NASA: Aerospace Materials and Applications , Chapter 6 — Materials for Spacecraft (Miria M. Finckenor), 2018.
