Wikimedia Commons // Public Domain
Wikimedia Commons // Public Domain

The Apollo Astronaut Who Was Allergic to the Moon

Wikimedia Commons // Public Domain
Wikimedia Commons // Public Domain

The inside of Apollo 17’s lunar module smelled of gunpowder. It was December 1972, the last of NASA’s manned moon missions, and astronauts Eugene Cernan and Harrison “Jack” Schmitt had just finished a successful survey of the Valley of Taurus-Littrow, a spot on the southeastern “coast” of the Moon’s Sea of Serenity. They had returned to the landing module with their spacesuits caked in moondust.

The men brushed themselves off and removed their helmets. Suddenly, Schmitt began having a sneezing fit. His eyes reddened. His throat itched. His sinuses clogged.

“I didn’t know I had lunar dust hay fever,” Schmitt said. Listening in, men stationed back on Earth began to bust Schmitt’s chops over the radio transmission. “It’s funny they don’t check for that,” said Joseph Allen at Mission Control. “Maybe that’s the trouble with the cheap noses, Jack.”

Schmitt, it turns out, was basically allergic to the Moon.


Of all the difficulties involved with putting a man on the Moon, “the major issue the Apollo astronauts pointed out was dust, dust, dust,” Larry Taylor, director of the Planetary Geosciences Institute, said in an interview with the Soil Science Society of America. The Apollo 11 astronauts griped that the “particles covered everything and a stain remained even after our best attempts to brush it off.” An Apollo 12 crew member moaned that the lunar module “had so much dust that when I took my helmet off, I was almost blinded.”

Moondust may look soft and pillowy, but it’s actually sharp and abrasive, largely the detritus of micrometeorite impacts. With no wind or moving water on the Moon’s surface, moondust never erodes. Effectively, no natural process exists on the lunar surface that can round its edges. When astronauts inhale what is essentially finely powdered glass, it becomes a huge health hazard [PDF]: The powder is so jagged that a deep breath could cause it to lodge in the lungs and pierce the alveolar sacs and ducts [PDF], resulting in a lunar version of “stone-grinder’s disease,” or silicosis, a deadly condition that commonly killed coal miners (and still kills 100 Americans a year). To complicate matters, lunar dust also contains a lot of iron—and this iron-laden dust has recently been implicated in hypertension among Apollo astronauts [PDF].

Reports of moondust misadventures from previous Apollo missions never deterred Harrison Schmitt. After all, the Harvard-educated geologist had dedicated the better part of a decade to studying the Moon’s landscape. Working for the U.S. Geological Survey’s astrogeology department, he used telescope photos to map the Moon and planets. So when the NASA asked if any scientists were interested in visiting space, Schmitt hardly hesitated. “I thought about 10 seconds and raised my hand and volunteered,” he said in a 1999 oral history project with NASA.

No astronaut knew more about lunar geology than Schmitt. Previously, every other Apollo flyboy had had a background as a military pilot. Schmitt was the first, and only, professional scientist to walk on the Moon. As a result, the press didn’t romanticize or hype the geologist astronaut. The New York Times described the 37-year-old as a “quiet, serious bachelor who does not own a television set or a stereo.” As he trained to go to the Moon, completing a 53-week flight training course and logging 2100 hours of flying time, the scientist never imagined that he would wind up being allergic to the lunar dust and rocks he had spent years studying from afar.

Schmitt in the Lunar Roving Vehicle (LRV) during the third Apollo 17 extravehicular activity (EVA) at the Taurus-Littrow landing site. Image Credit: Getty Images


In December 1972, Schmitt landed in the Moon’s Valley of Taurus-Littrow, surrounded by mountains and endless stretches of moondust. During their first moonwalk, the lunar roving vehicle lost a fender. The tires spun, and the rover kicked up a cloud of dust.

The sediment got lodged in every wrinkle, fold, nook, and cranny of Schmitt’s spacesuit. The dust “gummed up the joints” of his suit so badly that he had trouble moving his arms. The powder chewed up his footwear, too. “The dust was so abrasive that it actually wore through three layers of Kevlar-like material on Jack’s boot,” Taylor said.

When the astronauts returned to the lunar module, it took forever to brush the dust off. Schmitt later complained [PDF] of “a lot of irritation to my sinuses and nostrils soon after taking the helmet off ... the dust really bothered my eyes and throat. I was tasting it and eating it.” The symptoms lasted for about two hours. His condition was consistent with the findings of Dr. Bill Carpentier, a NASA doctor who had evidence suggesting the dust could cause allergic responses [PDF].

Schmitt's pesky moon allergies couldn't stop his true grit. Thanks to his background as a geologist, Apollo 17 collected more rock samples than any other mission. One sample, the 4.2-billion-year-old hunk of rubble called “Troctolite 76535,” later helped unlock secrets of the Moon’s magnetic field [PDF].

Schmitt also discovered bright orange beads of volcanic glass on the Moon’s surface. Not only did these samples prove that the Moon was once volcanically active, they also provided evidence that it contained water. And before they packed for home, Schmitt and his fellow Apollo 17 astronauts snapped a photo of Earth. Today, it’s one of the most iconic photographs of our home: the Blue Marble.

Anne Dirkse, Flickr // CC BY-SA 2.0
10 Astonishing Things You Should Know About the Milky Way
Anne Dirkse, Flickr // CC BY-SA 2.0
Anne Dirkse, Flickr // CC BY-SA 2.0

Our little star and the tiny planets that circle it are part of a galaxy called the Milky Way. Its name comes from the Greek galaxias kyklos ("milky circle") and Latin via lactea ("milky road"). Find a remote area in a national park, miles from the nearest street light, and you'll see exactly why the name makes sense and what all the fuss is about. Above is not a sky of black, but a luminous sea of whites, blues, greens, and tans. Here are a few things you might not know about our spiraling home in the universe.


The Milky Way galaxy is about 1,000,000,000,000,000,000 kilometers (about 621,371,000,000,000,000 miles) across. Even traveling at the speed of light, it would still take you well over 100,000 years to go from one end of the galaxy to the other. So it's big. Not quite as big as space itself, which is "vastly, hugely, mind-bogglingly big," as Douglas Adams wrote, but respectably large. And that's just one galaxy. Consider how many galaxies there are in the universe: One recent estimate says 2 trillion.


artist's illustration of the milky way galaxy and its center
An artist's concept of the Milky Way and the supermassive black hole Sagittarius A* at its core.
ESA–C. Carreau

The Milky Way is a barred spiral galaxy composed of an estimated 300 billion stars, along with dust, gas, and celestial phenomena such as nebulae, all of which orbits around a hub of sorts called the Galactic Center, with a supermassive black hole called Sagittarius A* (pronounced "A-star") at its core. The bar refers to the characteristic arrangement of stars at the interior of the galaxy, with interstellar gas essentially being channeled inward to feed an interstellar nursery. There are four spiral arms of the galaxy, with the Sun residing on the inner part of a minor arm called Orion. We're located in the boondocks of the Milky Way, but that is OK. There is definitely life here, but everywhere else is a question mark. For all we know, this might be the galactic Paris.


If you looked at all the spiral galaxies in the local volume of the universe, the Milky Way wouldn't stand out as being much different than any other. "As galaxies go, the Milky Way is pretty ordinary for its type," Steve Majewski, a professor of astronomy at the University of Virginia and the principal investigator on the Apache Point Observatory Galactic Evolution Experiment (APOGEE), tells Mental Floss. "It's got a pretty regular form. It's got its usual complement of star clusters around it. It's got a supermassive black hole in the center, which most galaxies seem to indicate they have. From that point of view, the Milky Way is a pretty run-of-the-mill spiral galaxy."


On the other hand, he tells Mental Floss, spiral galaxies in general tend to be larger than most other types of galaxies. "If you did a census of all the galaxies in the universe, the Milky Way would seem rather unusual because it is very big, our type being one of the biggest kinds of galaxies that there are in the universe." From a human perspective, the most important thing about the Milky Way is that it definitely managed to produce life. If they exist, the creatures in Andromeda, the galaxy next door (see #9), probably feel the same way about their own.


John McSporran, Flickr // CC BY 2.0

We have a very close-up view of the phenomena and forces at work in the Milky Way because we live inside of it, but that internal perspective places astronomers at a disadvantage when it comes to determining a galactic pattern. "We have a nice view of the Andromeda galaxy because we can see the whole thing laid out in front of us," says Majewski. "We don't have that opportunity in the Milky Way."

To figure out its structure, astronomers have to think like band members during a football halftime show. Though spectators in the stands can easily see the letters and shapes being made on the field by the marchers, the band can't see the shapes they are making. Rather, they can only work together in some coordinated way, moving to make these patterns and motions on the field. So it is with telescopes and stars.


Interstellar dust further stymies astronomers. "That dust blocks our light, our view of the more distant parts of the Milky Way," Majewski says. "There are areas of the galaxy that are relatively obscured from view because they are behind huge columns of dust that we can't see through in the optical wavelengths that our eyes work in." To ameliorate this problem, astronomers sometimes work in longer wavelengths such as radio or infrared, which lessen the effects of the dust.


Astronomers can make pretty reasonable estimates of the mass of the galaxy by the amount of light they can see. They can count the galaxy's stars and calculate how much those stars should weigh. They can account for all the dust in the galaxy and all of the gas. And when they tally the mass of everything they can see, they find that it is far short of what is needed to account for the gravity that causes the Milky Way to spin.

In short, our Sun is about two-thirds of the way from the center of the galaxy, and astronomers know that it goes around the galaxy at about 144 miles per second. "If you calculate it based on the amount of matter interior to the orbit of the Sun, how fast we should be going around, the number you should get is around 150 or 160 kilometers [93–99 miles] per second," says Majewski. "Further out, the stars are rotating even faster than they should if you just account for what we call luminous matter. Clearly there is some other substance in the Milky Way exerting a gravitational effect. We call it dark matter."


Dark matter is a big problem in galactic studies. "In the Milky Way, we study it by looking at the orbits of stars and star clusters and satellite galaxies, and then trying to figure out how much mass do we need interior to the orbit of that thing to get it moving at the speed that we can measure," Majewski says. "And so by doing this kind of analysis for objects at different radii across the galaxy, we actually have a fairly good idea of the distribution of the dark matter in the Milky Way—and yet we still have no idea what the dark matter is."


andromeda galaxy
The Andromeda galaxy
ESA/Hubble & NASA

Sometime in the next 4 or 5 billion years, the Milky Way and Andromeda galaxies will smash into each other. The two galaxies are about the same size and have about the same number of stars, but there is no cause for alarm. "Even though there are 300 billion stars in our galaxy and a comparable number, or maybe more, in Andromeda, when they collide together, not a single star is expected to hit another star. The space between stars is that vast," says Majewski.


There are countless spacecraft and telescopes studying the Milky Way. Most famous is the Hubble Space Telescope, while other space telescopes such as Chandra, Spitzer, and Kepler are also returning data to help astronomers unlock the mysteries of our swirling patch of stars. The next landmark telescope in development is NASA's James Webb Space Telescope. It should finally launch in 2019. Meanwhile, such ambitious projects as APOGEE are working out the structure and evolution of our spiral home by doing "galactic archaeology." APOGEE is a survey of the Milky Way using spectroscopy, measuring the chemical compositions of hundreds of thousands of stars across the galaxy in great detail. The properties of stars around us are fossil evidence of their formation, which, when combined with their ages, helps astronomers understand the timeline and evolution of the galaxy we call home. 

Mysterious 'Hypatia Stone' Is Like Nothing Else in Our Solar System

In 1996, Egyptian geologist Aly Barakat discovered a tiny, one-ounce stone in the eastern Sahara. Ever since, scientists have been trying to figure out where exactly the mysterious pebble originated. As Popular Mechanics reports, it probably wasn't anywhere near Earth. A new study in Geochimica et Cosmochimica Acta finds that the micro-compounds in the rock don't match anything we've ever found in our solar system.

Scientists have known for several years that the fragment, known as the Hypatia stone, was extraterrestrial in origin. But this new study finds that it's even weirder than we thought. Led by University of Johannesburg geologists, the research team performed mineral analyses on the microdiamond-studded rock that showed that it is made of matter that predates the existence of our Sun or any of the planets in the solar system. And, its chemical composition doesn't resemble anything we've found on Earth or in comets or meteorites we have studied.

Lead researcher Jan Kramers told Popular Mechanics that the rock was likely created in the early solar nebula, a giant cloud of homogenous interstellar dust from which the Sun and its planets formed. While some of the basic materials in the pebble are found on Earth—carbon, aluminum, iron, silicon—they exist in wildly different ratios than materials we've seen before. Researchers believe the rock's microscopic diamonds were created by the shock of the impact with Earth's atmosphere or crust.

"When Hypatia was first found to be extraterrestrial, it was a sensation, but these latest results are opening up even bigger questions about its origins," as study co-author Marco Andreoli said in a press release.

The study suggests the early solar nebula may not have been as homogenous as we thought. "If Hypatia itself is not presolar, [some of its chemical] features indicate that the solar nebula wasn't the same kind of dust everywhere—which starts tugging at the generally accepted view of the formation of our solar system," Kramer said.

The researchers plan to further probe the rock's origins, hopefully solving some of the puzzles this study has presented.

[h/t Popular Mechanics]


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