Mary Beth Wilhelm is a planetary scientist and astrobiologist at NASA Ames Research Center in Mountain View California. She specializes in studying areas on Earth that have climates and landscapes similar to those found on Mars -- and that means some of the driest and most remote parts of the planet. She talked to us about what it's like to travel to the coldest and hottest places in the world where, in some cases, rain only falls once every decade.

What exactly does a planetary scientist do?

My work is a combination of fieldwork and lab work and a lot of writing. Way more writing than I ever expected going into the sciences. In my research, I'm mostly interested in searching for the signs of life on Mars. You could describe me as an astrobiologist -- understanding the origin of life on Earth and looking for it outside of Earth.

How can you find life on other planets by looking at Earth?

Basically I use these really Mars-like places on Earth as a testbed to understand how all of the components that make up life are preserved in those types of environments. One of the most Mars-like places is the Atacama Desert. You can look at dryness as a function of precipitation or you can look at it as the availability of water for life. In Yungay, a region in northern Chile, it only rains there once a decade, about 2 - 5 mm. Barely enough to even form a puddle. There's no plants, no lichens or mosses. I'm doing a study right now and don't even see evidence for activity of soil bacteria. Even the coastal city of Antofagasta in northern Chile, which is on the Pacific Ocean, is about 30 times dryer than the Mojave Desert.

How did it get so dry there?

It has to do with the Andes. They're tall and block the trade winds that go from the Atlantic towards the Pacific. Hot dry air descends on the desert. Offshore on the Pacific Ocean the currents come up from Antarctica they're cold and therefore the air doesn't pick up any moisture. It's' been like this for millions of years. It has been Mojave Desert-level dry for a hundred million years, a couple rain storms per year. And then it's been even drier, 100 times dryer than the Mojave, for 10 to 15 million years.

Are you planning to view the solar eclipse next Monday (8/21/17)? No, I mean are you really planning how you'll watch this rare celestial event? Finding the appropriate solar-filter glasses is just one piece of the puzzle, and certainly a very important one. You should also prepare yourself to be part of an astronomically huge migration of people as millions of sky watchers gravitate to the best viewing spots across the US.

What's Happening

A solar eclipse occurs when the Moon's path takes it between the Earth and the Sun. Monday's eclipse is unique because it is a total solar eclipse. Those in the right spot will experience "totality", where the Moon completely obscures the Sun, leaving only its corona fringe visible. The Moon's shadow will cast an eerie temporary twilight in the middle of the day. It's a sort of otherworldly phenomenon that eclipse experts say is worth whatever effort it takes to experience.

True totality will only happen for people who are at the correct latitude to be aligned with the Sun and Moon…i.e. folks inside the Moon's shadow. Viewers at off-axis latitudes will have to settle for a less-spectacular partial eclipse, as some part of the Sun will always remain visible for them.

Over a period of about 1.5 hours, the Moon's shadow will trace a diagonal path approximately 70 miles wide from Oregon to South Carolina. This "Path of Totality" through the US heartland is why many are calling Monday's event "The Great American Eclipse". This presents an opportunity for viewing a total eclipse to the 12 million+ Americans who live within the path of totality as well as the additional millions who plan to travel there.

Unless you work in a lab, it's possible that you've never seen a pipette in person and only have a vague idea about what it does. But any scientist that has ever worked with liquids will likely say the pipette is one of the most essential tools in the lab. Modern versions of the tool require just a press of a button to pick up a specific volume of liquid and move it. It's a bit like an eyedropper, but with the ability to control specifically how much liquid you are picking up and dispensing. The pipette is most commonly used in genetic research, chemistry, microbiology, and drug development.

Photo credit: Flickr user gemmerich via Creative Commons

In what is probably the most horrifying revelation in all of these lab tool histories so far, the reality about life before formal pipetting is that when scientists didn't have proper tools to move liquids around they just used a straw and their own mouths to create suction. According to a paper titled "Hazards of Mouth Pipetting," produced by the US Army Biological Laboratories in 1966, one of the earliest recorded examples of the hazards of using one's mouth for this purpose came in 1893 when a doctor accidentally sucked a bunch of Typhoid bacteria into his mouth. The paper went on to express concern that it was much too easy to inhale vapors, especially from radioactive solutions, even when the liquid being transferred never made contact with a scientist's mouth.

It's remarkable, given the history of pipettes, that the "mouth pipetting" method managed to continue into the 60s. According to the US Army paper: "the method of avoiding pipetting hazards is so elementary, so simple, and so well-recognized that it seems redundant to mention it." But, nonetheless, the paper goes on to say that only a few institutions at the time had issued rules that forbade scientists from using their mouths to move infectious and toxic materials around their labs. In fact, Manhattan Project scientist Lawrence Bartell accidentally ingested plutonium using this method -- luckily he lived to tell the tale.

Credit: Sarah Harrop, Medical Research Council

Scientists certainly had the tools available to them at that time. The earliest pipettes were invented by Louis Pasteur, one of the scientists responsible for proving the validity of germ theory. For a few hundred years before Pasteur came around science had suspected the existence of microorganisms, but had never been able to prove their existence. Pasteur managed to show that microbes were responsible for food going bad by closely studying the fermentation of milk and wine. The result of this research was twofold. First, of course, was his most famous achievement: developing the method of pasteurization, which uses heat to remove bacteria from food. The second was the creation of rudimentary pipettes, know today as the Pasteur Pipette, which he deemed essential to prevent liquids from becoming contaminated when they were moved from place to place in his lab. The new method used thin glass tubes with a rubber bulb at the end, which created suction. Pasteur Pipettes don't have the measuring sophistication that modern pipettes have, but they are still in use today (now also called "transfer pipettes" they're usually made of one single piece of plastic).

Sometimes scientists need to break down small things into even smaller things. Blood needs to become platelets, plasma, and cells. Cells need to become organelles. Gases need to become isotopes. One of the best ways to achieve this is to put these items into a centrifuge, spin them around at super high speeds, and use the force of that movement to break them up into their individual parts.

The first centrifuge was created by Antonin Prandtl, a German cafe owner. According to a biography written by Prandtl's grand-niece, the design of the device, which he published in a polytechnical journal, was for a machine that worked continuously to separate milk from its fat. There is little known about Antonin or his design, but it likely was created sometime during the mid-1800s (possibly around 1850). Much more is known about Antonin's nephew, Ludwig, an engineer and Nazi sympathizer who would eventually become one of the world's experts on fluid dynamics. Ludwig's father, Antonin's brother, ultimately took most of the credit for the design of the first centrifuge by perfecting the mild-separating system and showing it at the 1875 World Exhibition in Frankfurt.

Photo credit: Flickr user gemmerich via creative commons

The next big upgrade to the device, and the one that brought the centrifuge into the laboratory, was invented by Swedish Chemist Theodor Svedberg. In his lab Svedberg was studying colloids -- a substance, which, in the simplest possible terms, is made up of matter in one type of state evenly dispersed within matter that is in another type of state. (Whipped cream, for example, is a colloid of gas and liquid.) Svedberg wanted to better understand the (much more complex than whipped cream) colloids he was studying and so he created a device that would separate the colloids out into their individual parts.

Hello, San Francisco. I can't believe this crowd. Seriously, I can't believe that we have to come out. Now a speech from a guy with a high-school diploma.

I speak today not just to those who agree with me, to the choir, but also to those who don't. I'm assuming we begin from the same basic principles. We may differ in terms of the method, but I think we can agree on the goal: that we all want to leave a better world and life for our children, our loved ones, our communities. Science is the key way to achieve that.

If I'm going to talk about science, I want to define my terms. To begin with what is science, this morning the Internet described it to me as "the intellectual and practical activity encompassing the systematic study of the structure and behavior of the physical and natural world through observation and experiment.

It doesn't really roll off the tongue. How about this? Science is the systematic reduction of ignorance. Science is not an edifice or a citadel; it is a process. To riff off Robert Pirsig, "Science is not a thing. It is an event. It is a practice and most often this practice is done by scientists."

Science could never get done without the right tools. And all that gear has to come from somewhere. Many of the gadgets sitting on laboratory shelves around the world have histories just as interesting as the discoveries they've made. Each month we're telling the stories of how the most important lab tools came to be.

There are few more essential tools to a scientist then the ability to keep contaminants out of their research. Dust, microbes, and even vapors can screw up delicate experiments. And as science gets more and more precise, sometimes even a single atom out of place could mean the difference between successful science and total failure. This is why we have cleanrooms. They control the level of contaminated air inside a space and allow scientists to do delicate work without fear that a rogue element will upend everything.

Willis Whitfield invented the cleanroom in 1962. It was a revolution at the time -- the design schematics for the first "ultra-clean room" even has a patent: US3158457 A. But 1962 wasn't all that long ago. It's hard to believe that no one was protecting their environments from contamination before then.

Photo Credit: NASA/Chris Gunn

People were certainly trying. According to a paper on the history of the cleanroom by Daniel Hollbrook, a historian at Marshall University, the earliest people to make an attempt at creating controlled environments were watchmakers. It makes sense if you think about it -- they were dealing with teeny tiny parts that had to move in tandem and even a small speck of dirt would throw off their delicate work. In the 1850s one American watch factory, he says, solved the problem of dirt getting into their watch parts by physically moving their entire company from the polluted city of Roxbury, Massachusetts, to a more rural part of the state. Then they located the actual room where they built the watch mechanics above ground level. It was one of the first instances of an isolated area dedicated to building mechanisms.

Most of us would not go on a long hike in a brand-new pair of boots. You first want to put a few casual miles on them to soften the material and make sure they perform well. This preliminary effort can help you avoid a lot of misery out on the trail. If you think of a spacewalk as the ultimate hike (who doesn't?), then it's easy to understand why spacesuits undergo the same type of break-in process before they're ever sent into space.

Long before a spacesuit is used on a spacewalk, its components have gone through an arduous break-in process. (NASA photo)

About the Suit

Before getting into the specifics of how spacesuits are broken-in, a little background on the suit is warranted. The NASA suit that astronauts have used for spacewalks since the dawn of the space shuttle era is the Extra-Vehicular Mobility Unit (EMU). The EMU is a modular design comprised of a handful of interchangeable subcomponents (helmet, upper torso, lower arms, gloves, etc.). Many of the various subcomponents that make up the suit are available in multiple sizes.

When an astronaut gets sized for an EMU, they do not get a dedicated suit to call their own. Rather, the product of the arduous sizing process is a chart illustrating the specific subcomponent sizes which provide the best fit for that astronaut. Whenever the astronaut needs a suit for a training event or mission, technicians reference the chart to pull the appropriate hardware off the shelf and assemble a correctly-sized EMU. The suit is torn down after the event and the individual subcomponents are placed back into inventory.

An EMU stand holds the suit upright and allows the occupant to focus on the necessary cycling motions. (James Lemon photo)

Over time, worn-out subcomponents get retired and replacements are manufactured. This new hardware undergoes rigorous inspection and testing before it can be added to the inventory. Yet, even more must be done before these EMU bits are used on an astronaut's suit.

New EMU subcomponents are required to undergo a break-in process called "cycling". Whereas factory testing is typically performed using only the individual subcomponent, cycling introduces the piece into a complete EMU. The intent of this effort is to begin softening the stiff layers of new fabric and to verify that the part performs properly in all respects. This is done by exercising the hardware with repetitive, spacewalk-inspired motions. For those who participate in cycling events, the term "exercising" is particularly appropriate.

Boeing recently unveiled the suit that astronauts will be wearing when they ride their upcoming Starliner capsule to the International Space Station (ISS). Officially called the Starliner Ascent and Entry Suit, it also answers to "Starliner spacesuit". Aside from its bold "Boeing blue" color, the Starliner spacesuit has numerous features worth noting. It is quite different in several ways from any suit that astronauts have ever worn before. These differences reflect an emphasis on mobility and comfort, efforts to blend the suit with its host spacecraft, and the specific emergency scenarios that the suit is designed for.

The Basics

The most important thing to understand about the Starliner spacesuit is its role an "ascent and entry" suit. As such, it is only designed to be worn during launch and landing of the spacecraft. You won't see astronauts spacewalking in this suit (at least not for long!). The primary function of an ascent and entry suit is to keep the occupant alive if there is a problem inside the crew compartment during launch or landing. The scenarios with the highest probability (though still relatively unlikely) are loss of cabin pressurization or an internal fire.

Before getting to the specifics of the Starliner spacesuit, let's discuss the attributes of ascent/entry suits in generic terms. Previous generations of these suits have been derived from the pressure garments worn by pilots of high-altitude reconnaissance aircraft like the U-2 and SR-71. In some cases, the differences were negligible. Whether worn in an airplane or a spacecraft, the job such a suit is to provide its occupant with a tolerable atmospheric pressure, even when the outside pressure conditions are lethal.