Building on existing UCR strengths in biogeochemistry, Earth history, and astrophysics, the Alternative Earths Astrobiology Center is cultivating a ‘search engine’ for life on planets orbiting distant stars—so-called exoplanets—and other worlds beyond Earth using the best possible template: the billions of years that Earth was teeming with simple life, long before the evolution of animals. What would Earth have looked like if analyzed remotely over that long history? Those early microbial organisms were constantly at work reshaping the chemistry of the oceans and atmosphere. What traces of their livelihoods would they have left behind? On modern Earth, the strongest sign of life, or biosignature, is the oxygen that plants produce and animals breathe. But our home planet was inhabited for billions of years before any detectable traces of oxygen accumulated in the atmosphere. So, what information about the processes that combined to sustain Earth’s dynamic habitability over those billions of years could we glean if we had snapshots of our evolving planet? Earth’s rock record provides a means to tackle this question via an array of diverse windows into past states of inhabitation—what we can think of as ‘Alternative Earths.’ Already, faculty and staff from both departments are pooling efforts in research, teaching, education and outreach.
"The discovery of life beyond Earth is not a question of if but when. When it happens, we want UCR to be well placed in the headlines."
Already UC Riverside is a world leader in astrobiology research emphasizing the Earth as an analog for exploring habitable conditions elsewhere—be it on Mars, an icy moon of Jupiter, or an expolanet light-years away. In 2015 the NASA Astrobiology Institute awarded Lyons and his UCR Earth Sciences-based team $7.5 million over five years to develop a research initiative around a single unifying question: How has Earth remained persistently inhabited through most of its dynamic history, and how do those varying states of inhabitation manifest in the atmosphere? The expected outcomes of the new initiative feature a series of modeled Earth states, each tied to very different influences but linked through the common theme of persistent inhabitation. It is conceivable that each of Earth’s widely varying planetary states translates to a particular atmospheric composition that could one day be detected on an exoplanet. No research group in the world has been assembled with such a specific emphasis on sustained habitability. By leveraging existing resources on campus and in the region under the umbrella of a UCR Astrobiology Center, we will seize the opportunity to forge a broader whole that will be much greater than the sum of its parts.
The number of known or suspected Earth-sized planets orbiting distant stars is now in the hundreds. Yet despite these extraordinary recent developments in exoplanet detection and characterization, UCR has no such expertise. With the addition of key faculty, the UCR Astrobiology Center’s research objectives could expand to encompass detection of planets outside our solar system, assessment of their habitability informed by the modeled Earth states, and ultimately, proof of the presence of life. Federal funding opportunities abound: this hiring effort would take advantage of a large number of existing and future imaging and spectroscopic instruments on the largest ground- and space-based telescopes to survey nearby stars for the presence of orbiting exoplanets and signs of inhabitation. Indeed, no other research program in the world bridges Early Earth and exoplanet research the way we envision for UCR (see summary figure on previous page).
Over the longer term, we see exciting potential to broaden UCR’s astrobiology mission even further. Astrobiology is a multidisciplinary field assimilating expertise in many different areas including astrophysics, geosciences, planetary sciences, chemistry, biology, data analytics and statistics. A center made world-class by its unique focus on the bridge between Early Earth and exoplanetary research could eventually bring together this much wider range of UCR expertise and under the same umbrella—creating new research and funding opportunities for all involved.
The center will develop new courses and coordinate existing ones at both undergraduate and graduate levels in a variety of topics related to astrobiology, habitability and exoplanetary science. The center is already establishing and promoting educational cooperation and research opportunities between UCR and NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, including arranging guest lectures by JPL science staff. The center will organize workshops for UCR faculty and students during the year as well as a weekly seminar series on habitability. The development of a NASA videoconferencing facility in Geology 2460 is making possible real-time collaboration with remote NASA colleagues. A ten-week virtual workshop with colleagues from UCLA and MIT has already taken place, along with a series of virtual seminars given by leading astrobiology experts based around the country. Capitalizing on the science communication expertise within the NASA Astrobiology team (Sarah Simpson), the center is also offering science communication workshops at UCR and at partner institutions around the country.
The educational aim of the center is to train the next generation of researchers in astrobiology, geochemistry, planetary astrophysics, and atmospheric sciences with analytics and technical expertise to develop innovative ways to study some of humanity’s deepest questions. Already UCR’s affiliation with the NASA Astrobiology Institute is opening up international educational opportunities for current graduate students and is drawing new, high-quality grad students and postdocs to UCR. Students from the center will also have the opportunity to take paid internship positions at NASA’s JPL through an existing five-year, $4.5 million NASA FIELDS (Fellowships and Internships in Extremely Large Data Sets) program led by Bahram Mobasher. (Indeed, the FIELDS program is already sponsoring a UCR astrobiology undergraduate for a 10-week internship at JPL this summer, followed by continued lab work at UCR in the fall.) The FIELDS program has also pledged to present free workshops to undergraduate and graduate students interested in data science, which is of particular importance for researchers using spectroscopic data to analyze exoplanets and their atmospheres.
Our center’s outreach goal is to promote UCR research, the fields of astrobiology and data science, and a variety of related NASA missions through the exchange of people, ideas, and hands-on activities at the local, national, and international levels. Locally, we envision the UCR Astrobiology Center as the hub for NASA astrobiology and citizen science in the Inland Empire. Staff working with UCR’s NASA Astrobiology Institute team (Sarah Simpson) and the Department of Physics and Astronomy (Mario De Leo¬–Winkler) have already been working together to reach out to the Riverside community and beyond through public lectures, picture exhibitions, telescope workshops and viewing events (total lunar eclipse and Mercury transit), and the design of a multidisciplinary, hands-on educational program called “Sensing the Universe,” which can be geared to everyone from preschool and high-school students to the general public. The team is laying the groundwork for offering workshops to people with disabilities (example: Sensing the Universe can be geared to the blind and deaf), and De Leo–Winkler is getting in closer touch with native Spanish speakers through a series of NASA astronomy talks in Spanish. At the international level, center staff collaborating with the Department of Earth Sciences recently hosted a Sensing the Universe program for visitors from Tohoku University in Sendai, Japan, and plans are underway to facilitate an exchange of outreach ideas with Universidad Autónoma de Baja California in Tijuana, Mexico.