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.

Why Do Astronauts Use Space Pens Instead of Pencils?

by Alex Carter

It's often said that NASA spent millions of dollars developing a pen that could write in zero gravity, while the Russians just used pencils. It was a warning about looking for a high-tech solution to a mundane problem, of American excess vs. Russian sensibility.

It's also entirely false.

To understand why NASA was so keen on a workable space pen, you have to understand that the pencil is not suited for space travel. The problem is that they have a habit of breaking, shattering, and leaving graphite dust behind. The wood, too, can make it a serious fire risk in the pressurized, oxygen-rich capsule. All of these common issues become life-threatening hazards in space.

Still, there were attempts to bring pencils into space. In 1965, the agency famously ordered 34 specially designed mechanical pencils in hopes of finding the perfect writing tool for astronauts. But at $128 each, they weren't exactly cheap, and it only got worse when the public got wind of the price. Thankfully, an alternative was not too far behind.

Astronaut Walt Cunningham, pilot of the Apollo 7 mission, uses the Fisher Space Pen while in flight.
Astronaut Walt Cunningham, pilot of the Apollo 7 mission, uses the Fisher Space Pen while in flight.

The Space Pen was invented by Paul Fisher, head of Fisher Pen Company. Unlike a typical pen, the Fisher Space Pen uses compressed nitrogen to force ink out of the nozzle, instead of using gravity to make it flow. This made it the ideal device for writing in space, while upside down, or submerged underwater. It wrote crisp and clean, without the safety concerns of a pencil.

Fisher contacted NASA to give his pens a try in 1965 and in 1967, after months of testing, they were impressed enough to bulk buy 400 of them for future missions. Contrary to those urban legends, NASA didn't commission the pen or contribute any funding to it. The Soviets soon ditched their grease pencils and were eventually buying the same Fisher pens as NASA, too. The price? After a 40 percent discount from Fisher, both space agencies were paying $2.39 a pen.

The Fisher Space Pens made their debut in 1968 on the Apollo 7 mission and have been involved in all manned missions since.

So, the short reason is that astronauts only used pencils when they were waiting for something better to come along. As soon as it did, they switched and never looked back. Even the Russians thought it was a good idea.

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New Study Says We Could Be Alone in the Universe

There's a good chance that humans are the only intelligent life in the galaxy, according to a new study submitted to the journal Proceedings of the Royal Society of London A. As Quartz reports, researchers at Oxford University's Future of Humanity Institute applied existing knowledge of biology, chemistry, and cosmology to the Drake equation (below). It was created by astronomer Frank Drake in 1961 as an attempt to calculate the number of intelligent civilizations that could be in our galaxy. He included factors like the average rate of star formation and the average lifespan of intelligent civilizations.

Image showing text of the Drake equation and explaining what each variable means
Equation: University of Rochester; Image: Hannah McDonald

They estimate there’s a 53 to 99.6 percent chance we’re alone in the galaxy, and a 39 to 85 percent chance we’re the only intelligent life to be found in the entire universe.

“Where are they?” the researchers ask, referring to the classic Fermi Paradox, which asserts that intelligent extraterrestrial beings exist and that they should have visited Earth by now. “Probably extremely far away, and quite possibly beyond the cosmological horizon and forever unreachable.”

Seth Shostak doesn’t buy it. Shostak is senior astronomer at the SETI Institute, a research organization that analyzes radio signals for signs of extraterrestrial intelligence. Part of the challenge with mathematical modeling like this, Shostak says, is that the data are limited; scientists just haven’t looked at very many star systems.

“I could walk outside here in Mountain View, California and not see too many hippos strolling the streets,” he tells Mental Floss. “But it would be incorrect for me to say on that rather limited basis that there’s probably no hippos anywhere. It’s a big conclusion to make on the basis of a local observation.”

Moreover, they may not even know what to look for in the solar systems they have reviewed. The SETI Institute examines radio communications and light signals, but there’s always the possibility that an intelligent civilization has attempted to contact us using means we may not have developed or even considered yet.

The Fermi Paradox itself may be naïve in its understanding of the universe, Shostak says. “You could have said the same thing about Antarctica in the 1700s. A lot of people wondered, ‘Is there a continent down there?’ On the one hand, you could argue there was [a continent], and on the other hand, you could say, ‘Look, there’s an awful lot of water in the Pacific and the Atlantic, and there’s no continents there, so why should there be one at the bottom of the ocean?’”

In other words, any conclusions about the existence of extraterrestrial intelligence are likely to be presumptive, made before any solid data is released or discovered. The truth may be out there, Shostak says. We just haven’t found it yet.

[h/t Quartz]


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