Life in This United Space

You might dream of a years-long expedition through space. Or perhaps the thought of Matt Damon’s ordeal in The Martian makes you break into a cold sweat. Whether you’d rather enjoy an earthbound moon bounce or do some real moon walking, we’ve all spent some time in awe of the night sky.

Some Badgers spend more time stargazing and galaxy-tracking than others. They do so in the hope of finding something extraordinary — ancient galaxies, new life, answers to age-old questions. There are literally limitless opportunities for exploration in outer space, and each endeavor into the otherworldly could help improve everyday life on Earth with new technologies, a better understanding about our planet, and insight into the origins of life itself.

From the launch of the United States’ first satellites to today’s Mars rovers and the James Webb Space Telescope, the UW has played a significant role in exploring humanity’s final frontier.

Neil Armstrong may have taken one small step and a big leap on the moon, but any feat in space first requires countless steps made by thousands of interdisciplinary scientists on Earth. With world-renowned organizations like the Space Science and Engineering Center (SSEC) and an impressive history of Badger space pioneers, the UW is responsible for many bounds forward in our understanding of Earth and the cosmos.

Take, for example, Verner Suomi, a professor who taught on campus for nearly 40 years, the father of satellite meteorology, and a cofounder of the SSEC. His invention of the multicolor spin-scan radiometer — a camera that could scan the Earth from a geosynchronous orbit — is responsible for the very first color images of our planet taken from a civilian spacecraft, and for today’s weather-tracking capabilities.

Suomi was primarily concerned with looking back at Earth to monitor its atmosphere and weather conditions, but the spin-scan camera opened the door to imaging and exploring other planets in our system, too. With this technology, scientists were able to take the first pictures of Jupiter, Saturn, and Venus from a spacecraft and study the atmospheres of each planet more effectively.

Sanjay Limaye PhD’77 — a distinguished scientist who has worked at the SSEC since 1980 — was one of Suomi’s graduate students. When the Mariner 10 mission to Mercury and Venus launched in 1973, Suomi was on the imaging team, and Limaye by extension. In February 1974, the mission reached Venus.

“The success of that project shaped my whole career,” Limaye says.

He has since studied cloud motions in the atmospheres of Venus, Jupiter, Saturn, Uranus, and Neptune through expeditions including NASA’s Pioneer Venus Orbiter and Voyager missions, as well as Venus Express, launched by the European Space Agency. His 2018 paper on the possibility of microbial life in the Venusian clouds was instrumental to the first privately funded mission to Venus, which is scheduled for launch in 2025.

If you know anything about Venus, you might be wondering why anyone would look to our neighboring planet for life. Its surface temperature is 750 Kelvin (890 degrees Fahrenheit), and its atmosphere is chock-full of sulfuric acid — it’s difficult to imagine any form of life adapting to such a corrosive, blistering environment.

But there’s an air of mystery in the Venusian atmosphere. Particularly in the dark patches that dot the planet’s clouds, which were first photographed from the Yerkes Observatory in Williams Bay, Wisconsin, in 1927. Scientists still don’t know what these patches might hold.

In 1967, biologist Howard Morowitz and astronomer Carl Sagan published a paper discussing the possibility of primitive life harbored in the planet’s clouds. When researchers received data about the conditions on Venus through Mariner 10 and subsequent missions, the idea of life on Venus was generally discarded.

Limaye wasn’t ready to dismiss the possibility. While conducting a workshop for teachers in Europe on classroom cloud-tracking activities, he offhandedly suggested that the contrast in the clouds of Venus could be bacteria. Afterward a researcher approached him about Thiobacillus

ferrooxidans — a type of bacteria that absorbs ultraviolet (UV) radiation and has a spectral signature that is very similar to the UV spectrum of Venus.

“I looked at the spectrum and my jaw dropped,” Limaye says. “The spectrum looked so much like the Venus UV absorption spectrum that it matched better than other substances that had been proposed.”

When Limaye approached other researchers, they all said the same thing: “Life? Venus? Clouds? Can’t be possible. It’s too dry.”

He kept digging anyway and learned more about the hardiest forms of life on Earth: extremophiles. First discovered in the 1960s by the late UW professor and pioneering microbiologist Tom Brock, extremophiles are microbes that can survive the harshest conditions that Earth — and even outer space — have to offer.

When Limaye resurrected a viable theory about how such life might have settled in the skies of Venus in 2018, it led to more studies that have since compelled Rocket Lab, an American aerospace company, to develop a new mission to Venus — one designed to take samples of Venusian clouds and search for organic material or other signs of life.

“It’s quite an astonishing timeline,” Limaye says, “how quickly things can happen when things just click.”

Extremophiles haven’t just sparked a renewed interest in microbial E.T.s on Venus. Brock’s discovery led to the classification of a new domain of earthly life, Archaea, which in turn furthered evolutionary research and enabled the development of today’s PCR tests used to monitor COVID-19. Extremophiles are also an important aspect of astrobiology, an interdisciplinary field that seeks to answer questions about the origin, evolution, and distribution of life in the universe.

Scientists need something concrete to study, and extremophiles provide a practical key to understanding how life might have adapted to Earth’s early environment and other seemingly inhospitable conditions throughout our solar system and beyond. Deinococcus radiodurans, for example — an extremophilic bacterium whose name means “strange berry that withstands radiation” — did just that (and more) after a year in low Earth orbit. Aside from enduring prolonged exposure to solar UV radiation, this type of bacteria survived severe temperatures, the vacuum of space, and extreme dehydration.

The existence of extremophiles has encouraged more and more scientists across a variety of disciplines to consider the possibility of extraterrestrial, microbial life. Since we know Earth can produce something like D. radiodurans, a.k.a. “the world’s toughest bacterium,” it’s reasonable to wonder about the small but mighty beings that could exist on other worlds.

Joshua Lederberg, a professor of genetics at the UW from 1947 to 1959 and a 1958 Nobel Laureate in Physiology or Medicine, was an early leader in the field of exobiology, astrobiology’s predecessor. In 1958 — the same year NASA was established — he published an article on the potential value of moondust in discovering the biochemical origins of life.

Lederberg was incorrect about the dusty, old secrets held within the moon’s soil, but his work encouraged some scientists to reexamine their approach to outer space and exploratory missions and helped lay the groundwork for today’s growing interest in astrobiology.

NASA began dabbling in exobiology early on by funding the development of an instrument designed to detect microbial life on other planets. But it wasn’t until the 1990s that the search for extraterrestrial life started to heat up. Possible signs of ancient life found on a Martian meteorite, data from the Hubble Space Telescope, and the completion of the Human Genome Project’s comprehensive human genetic map coalesced, reinvigorating thinking about the origins of earthly and extraterrestrial life.

Now known as astrobiology, the study of how life came to be and the exploration of how humans might detect other forms of life continues to be a growing field supported by NASA’s astrobiology program, various NASA laboratories, and a growing number of universities, including the UW.

Astrobiology@UW serves as a digital hub for anyone on campus interested in this highly interdisciplinary field. From this website, botanists, chemists, geneticists, space scientists, social scientists, and other researchers can connect with faculty and students interested in tackling questions as old as humanity itself. It also directs them to some of the UW’s astrobiology labs and consortia such as Metal Utilization Selection across Eons (MUSE), a NASA-funded research program on campus that examines how certain metals such as iron became so vital in the evolution of life.

The Baum Lab, supported by the Wisconsin Institute for Discovery (WID) and directed by WID fellow and UW botany professor David Baum, also seeks to understand the origins and evolution of life on Earth. Lena Vincent PhD’22, a molecular biologist by training, joined the lab as a doctoral student after deciding to pursue astrobiology.

“We all want to know where we came from,” she says, “and I think a logical extension of that is figuring out how we got here and thinking about the history of life on Earth and everything that’s led up to these moments that we’re experiencing now.”

In 2019, Vincent led a pioneering study in Baum’s lab to try to determine how life could result from the right mix of chemicals exposed to different conditions. Called chemical ecosystem selection, the experiment attempted to mimic the conditions on Earth four billion years ago by creating a soup of seawater, dissolved amino acids, sugars, organic compounds, minerals, and the necessary elements of nucleic acids. Over time, this collection of life’s building blocks exhibited some of the basic lifelike chemical reactions that are prerequisites for honest-to-goodness life.

Today, Vincent is going beyond early terrestrial life. As a postdoctoral fellow at NASA’s Jet Propulsion Laboratory managed by the California Institute of Technology, she’s seeking out life on ocean worlds — celestial bodies with surface or subsurface oceans. In the search for habitable planets and moons, liquid water is a key factor, along with a source of energy and the presence of organic molecules.

In our own solar system, two icy moons believed to have subsurface oceans, Jupiter’s Europa and Saturn’s Enceladus, are promising candidates for hosting extraterrestrial life. Vincent hopes that data from the James Webb Space Telescope (JWST) — Earth’s largest and most ambitious space observatory to date — will shine additional light on the feasibility of life on these moons and their mysterious oceans.

“James Webb is going to take a closer look at those and try to get some information about their composition, which might be indicative of what their oceans are made of,” she explains. “And if we can tell what their oceans are made of, that’ll give us really critical information to follow up on and figure out whether they can actually support life.”

With a $10 billion price tag, outer space’s most expensive Christmas present was the JWST, which launched on December 25, 2021, thanks to the work of thousands of scientists and engineers like Wei-Di Cheng ’93, a stress analyst who helped prepare the telescope

for space. Jointly developed by NASA, the European Space Agency, and the Canadian Space Agency, the JWST has been in the works for three decades. For the next five to 10 years

— and hopefully longer — the telescope will orbit our solar system’s sun just as Earth does, but with an extra million miles in between.

From its spot in orbit, the JWST has already taken the most detailed images of deep space and neighboring planets that humans have ever seen. Michael Maseda, an assistant professor of astronomy at the UW, was part of a team that built one of the JWST’s main instruments before coming to campus. He won’t take credit for the design — the team finished development of the instrument before his arrival — but he joined in time to help plan how scientists could make the most out of the telescope’s data. An astronomer focused on galaxy formation and the development of the early universe, Maseda is particularly interested in the JWST’s ability to travel through time.

“Light travels at a fixed speed, which means that the further away you’re looking, the longer light has taken to reach us,” he explains. “The ultimate realization of that is the JWST. By looking at distant things, we’re seeing the universe as it was a long time ago.”

The JWST will help scientists return to the beginning of time — about 13.8 billion years ago — to better understand how everything in the universe formed thereafter: stars, galaxies, and life itself.

And though the JWST wasn’t designed with the detection of extraterrestrial life in mind, its broad range of abilities will also aid researchers across disciplines, including Limaye and Vincent in their search for habitable conditions and life on other planets like Venus and moons like Enceladus.

Space scientists and astrobiologists aren’t the only ones who will benefit from continued exploration of the universe. The technology developed for space endeavors often results in everyday applications that make life on Earth easier. Thanks to Suomi, we have weather.com. Digital photography and the camera in your cell phone are largely results of NASA research and development. Instruments developed for the JWST will also advance night vision and thermal imaging technologies, and ultraprecise measuring systems used to build the JWST are being applied to ophthalmology to improve eye measurements and surgeries.

Then there’s the small matter of learning more about our origins. Every human being is born with an innate sense of wonder, and Badgers will never stop wondering why.