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Lunar dust sticks to everything!  It’s electrically charged!  It causes silicosis – astronauts on the Moon will get “black lung” disease, just like coal miners on Earth!  It’s so abrasive that under its obnoxious influence, moving parts slowly grind to a halt!  We can’t possibly cope with it!  So much for our plans to live and work on the Moon.  Guess we better stick to low Earth orbit.

An inhabitant of the lunar outpost deals with electrostatic charging of dust

To see the headlines and read some of the articles written on this topic over the last few years, one might get these impressions.  Is any of it true?  We actually have some hard data on this subject from measurements made on the Moon, experience dealing with dust during the Apollo missions, and from studies of returned lunar samples.  Being a unique product of its environment and the processes that made it, the dust of the Moon is fascinating material.  But is it a “show-stopper” for lunar return?

The surface of the Moon is covered by a fine powder, the ground-up reside of surface rocks produced over eons by micrometeorite bombardment.  The lunar soil or “regolith” covers everything and as a surface layer, its thickness increases with time.  Because lunar soil is formed by impact disaggregation, the edges of the dust grains are angular and sharp; no water or wind erosion is present to round off the grain edges as on the Earth.  The highly angular nature of lunar dust makes it self-compacting.  The upper few centimeters of soil are loose and fluffy, but the soil becomes considerably denser and well packed below this depth.  The dust is very fine grained; the mean grain size of lunar regolith is about 40 microns, roughly half the width of a human hair and a little coarser than talcum powder (about 10 microns), but hard and abrasive instead of soft.

The experience of the Apollo astronauts with lunar dust was that of the unprepared meeting the unknown.  We didn’t really understand the nature of the dust when the Apollo EVA suits and equipment were designed.  The crews went to the Moon with brushes to clean off dusty surfaces, but the adhesive nature of the dust (caused by the high degree of angularity of each grain) was not appreciated.  We also didn’t (and still don’t) understand the electrostatic charging properties that makes the dust “cling” to things, just as your clothes do when you first take them out of the dryer.

Dust got into everything during the Apollo missions.  Plastic bags refused to seal properly.  Fenders fell off the lunar rover, spraying dust all over the astronauts and their equipment.  Metal seal rings on space suits because clogged with dust and refused to seat properly.  As if all this weren’t bad enough, the astronauts themselves seemed to revel in getting down and wallowing in the stuff, covering their lower bodies with black, charcoal-like smudges.  After a hard day exploring the Moon, the crews noted the acrid smell of dust in the LM cabin (Buzz Aldrin said that it smelled like gunpowder.)   They breathed it into their lungs during the rest periods.

So, will lunar dust prohibit long-term habitation of the Moon?  Hardly.  Lunar dust has some unique properties that require careful consideration during the design of surface systems, but many of its alleged hazards can be avoided or mitigated.  One of the simplest things to do is to avoid contaminating things with dust.  The Apollo astronauts got covered with dust largely because they could not bend at the waist in their suits.  They would fall forward on their faces, stop the fall with one hand, grab a rock or tool with the other and then do a one-handed push-up to stand up.  This technique worked great – except for covering their suits with dust.  New suits will allow crews much greater flexibility, including the ability to bend at the waist.

Another idea is to keep the suits outside, leaving the interior of the habitat completely dust free.  But no matter how carefully we avoid it, some dust will get into places we want to keep clean.  Brushing only seems to grind it into porous surfaces.  But amazingly enough, we have found that much of the dust is magnetic.  Vapor-deposited metallic iron coats the surfaces of many mineral and glass dust grains.  This so-called “nanophase iron” (from its extremely small size) makes the dust easily attracted to a simple magnet.  A brush made with magnetic bristles will clean surfaces of most of the dust.  Incidentally, this same property permits the lunar soil to be fused into glass using low-energy microwaves, allowing us to “pave” roads and landing pads near and around the lunar outpost and to make bricks for construction and radiation shielding.

Although we do not fully understand the electrical charging properties of lunar dust, several experiments on current and future robotic missions will characterize these properties thoroughly.  The idea that charged dust can levitate and coat exposed surfaces is widely believed, but there is no solid evidence that this process occurs to any significant degree and there is considerable evidence that it does not.  The Surveyor 3 spacecraft, exposed on the lunar surface for over 30 months before examination by the Apollo 12 crew, was not covered by any significant amount of dust, other than that thrown up by the nearby landing of the Lunar Module.

Dust is both an asset and an issue.  We will process the dust of the Moon to extract useable products, like hydrogen and oxygen.  At the same time, we will learn how to live with it.  We’d better – dust occurs throughout the Solar System.  On Mars, it may have toxic chemical properties.  It’s not a deadly hazard –just another property of the new worlds to which we journey.

The TRW Capistrano Test Site

An item caught my eye this morning as I scanned the space news of the day. A famous aerospace facility, the TRW Capistrano Test Site in southern California is closing. The closure of a space facility is hardly news. In fact, such a headline could have been written any time over the last 20 years or so. But it got me thinking about the nature of the spaceflight business and why things seem to be more difficult to accomplish now than in the “good ol’ days” of Apollo.

I have argued elsewhere that for many reasons, the Apollo program is not a good template for new space endeavors. Yet the idea that we have somehow lost something – something vital – since the days of Apollo persists in the minds of many space advocates. They’re not wrong. Among other things, we have lost a significant and critical component of space exploration: a robust aerospace industrial infrastructure.

It was inevitable that with the end of the Cold War in the 1990’s, many high-technology companies with lucrative defense contracts would either re-focus their attention elsewhere (such as consumer products), be bought out by other larger companies, or simply go out of business. This was and is a critical issue for national security. Many of these companies made parts and subsystems vital to the proper functioning of national defense systems. I always thought that the real motivation of the Space Exploration Initiative of President George H. W. Bush in 1989 was to give this industrial base something difficult yet achievable to do, keeping them occupied with challenging work until they were needed for future defense production.

President Bush never articulated this reason for SEI and with his defeat in the election of 1992, it was easy to write off the SEI as a failed political “stunt” (a criticism I’ve never understood as no President has ever reaped any political gains from making a major space declaration and that includes John Kennedy, who was in serious political trouble in the south in 1963, even after shoveling tons of cash into Dixie from the Apollo program.) In the post-Cold War era, the fight against terrorism soon emerged as a national defense priority, but this war was different and largely fought with existing space assets and technologies.

A few isolated projects in the 1990’s were able to draw on the legacy technical base of the Cold War. The 1994 Clementine mission was a test of very low mass, low power sensors originally developed for defense, but applied to space exploration. Some of those instruments were manufactured by small companies that no longer exist. Over the course of the last five years, as we built the Mini-SAR instrument now orbiting the Moon on Chandrayaan-1, our progress was impeded because many of the parts and subsystems we needed were unavailable or only available from a small pool of vendors.

There were only two major bids to NASA in 2006 for the development of the new Orion spacecraft, the replacement for the Space Shuttle now under development. Contrast this with the 12 bids NASA considered for the Apollo spacecraft in 1961. The difference is not simply a consequence of corporations teaming with each other; joint proposals were common during the Apollo program. The difference is that there are few aerospace companies left. Many of the small high-technology companies and the highly skilled workforce that made up our industrial base during the Cold War are gone or have been absorbed into the body of Boeing-LockMart-Grumman.

The net effect of all this is less innovation and resourcefulness in the execution of space projects. As they age, the tendency is for organizations to continue to do business in a certain way because “that’s they way we’ve always done it.” Institutions become more risk averse and less enterprising with time. It’s no surprise to read headlines about new delays in the Orion CEV program and how our return to the Moon will take longer and cost more because we have come to expect that from our space program.

It’s not surprising. Just depressing.

When you write, do you capitalize the word “Moon?” And by this, I mean Earth’s Moon, Luna, the natural satellite of our home planet. Well, believe it or not, some of the longest, most vociferous, and yes – the dumbest – arguments I’ve ever had were over this issue.

In the preface of my book, The Once and Future Moon, I argued over a decade ago that the Moon was one of the largest satellites in the Solar System, our first destination off the Earth and mankind’s future home and thus, deserved the dignity of capitalization. I proceeded to capitalize the word “Moon” ever afterwards, except when I write for the press, which obstinately insists that it should be “moon” and ruthlessly proceeds to change all my brilliant text.

Why do so many editors insist upon this obnoxious practice? Apparently because the Associated Press (AP) Stylebook says so. To quote the black book of AP style directly:

AP capitalizes the proper names of planets, including Earth, stars, constellations, etc., but lowercases sun and moon.

Uh, OK. I guess that settles that. Ordinarily, I like ex cathedra pronouncements about language (Fowler was famous for them), but usually, they tend to have some reasonable basis in grammatical or linguistic fact. If there is such a basis for the “rule” given above, I don’t know what it is. I can speculate on one.

All of the major bodies of our Solar System have Roman (Latin) names – Mercury, Venus, Jupiter, etc. The only exceptions are the objects Earth, Moon, and Sun, whose names are derived from Germanic languages (the Latin equivalents are Terra, Luna, and Sol, respectively). Interestingly, the AP stylebook says to capitalize the Earth but not the Sun and Moon. My guess is that some classically educated nit-picker who was forced to sit through endless hours on the joys of the ablative absolute in Latin class decided that the Roman-named objects of the universe were worthy of linguistic worship, but the vulgar, barbarian Germanic names given to those other three bodies did not deserve to be capitalized.

I beg to differ. All three words are proper nouns; they refer to definite objects, one of which is home to humanity itself and another that soon will be. If these objects do not deserve capitalization, what does?

Simply put, the AP Stylebook is wrong. When referring to “the Moon” – that is, our Moon, Luna, site of Neil Armstrong’s landing in 1969 – the word should be capitalized. When referring to any moon, such as in “the moons of Jupiter”, it becomes a generic descriptor and hence, should not be capitalized. Our Moon is a world with its own history, one intimately entwined with our own. It has the material and energy resources needed to help us bootstrap a true spacefaring capability. It will one day become a second home for humanity.

After being criticized for ending too many sentences with a preposition, Sir Winston Churchill supposedly responded: “This is the sort of arrant pedantry up with which I will not put.” Whether Churchill said this or not (it is disputed, but it certainly sounds like him), it nicely captures my thoughts on this “controversy.”

Now, if we could just get the BBC to stop writing “Nasa” for “NASA”……