On June 23, the first images from the much-anticipated Vera C. Rubin Observatory atop Chile’s Cerro Pachón were shown to the world in grand fashion, coinciding with a celebration in Washington, D.C., hundreds of watch parties hosted across the globe, and a swell of pride felt by many at the University of California, Santa Cruz, whose researchers have played key roles in the observatory project—from its early stages through construction and commissioning.
The Rubin Observatory First Look event capped a massive $810 million effort over the past two decades that has involved hundreds of scientists, engineers, and support staff to build a first-of-its-kind observatory, whose mission is to produce an unprecedented astronomical dataset for studies of the deep and dynamic universe, to make the data widely accessible to a diverse community of scientists, and engage the public to explore the universe with them.
Rubin’s 8.4-meter Simonyi Survey Telescope is equipped with the largest camera ever built. The size of a small car but about twice as heavy, the digital camera has a whopping 3,200 megapixels—roughly the same number of pixels as 260 modern cell-phone sensors. It was managed and assembled at SLAC National Accelerator Laboratory, was recently installed on the telescope over the first few months of 2025, and will produce the enormous data needed for the ambitious Legacy Survey of Space and Time (LSST).
The survey, expected to begin in late 2025, will repeatedly scan the southern night sky for a decade, creating an ultra-wide, ultra-high-definition time-lapse record of the universe. This unique movie will bring the night sky to life, yielding a treasure trove of discoveries: asteroids and comets, pulsating stars, and supernova explosions, just to name a few. The LSST Camera will be used to capture images of billions of far-away galaxies, as well as closer, faint objects that don’t give off or reflect much light.
Key contributions and leadership
Steven Ritz, distinguished professor of physics at UC Santa Cruz, led the group that produced all the image products for the First Look event. On faculty at the Santa Cruz Institute for Particle Physics (SCIPP), Ritz studies dark energy and searches for signatures of dark matter. He became Project Scientist for the observatory’s construction in 2022.
“This project is another great example of strong collaboration between university groups and national laboratories. SCIPP has a long and successful history of working with SLAC on many projects,” Ritz said. “It is especially meaningful to me to be able to work with so many creative, hardworking, and talented people to design and build wondrous new facilities to enable new measurements at the crossroads between fields. This is also a great experience for UC Santa Cruz students.”
Ritz joined the observatory collaboration in 2013 as camera project scientist and deepened his involvement by serving in other roles in the years since. He is also a full member of the LSST Dark Energy Science Collaboration (DESC), serving over the years on the Collaboration Council and various committees, and his group contributed regularly to the teams that evaluate Camera test data and the impacts on systematic errors in dark energy science measurements.
The first UC Santa Cruz researcher involved with the observatory was SCIPP adjunct professor Terry Schalk. Now retired, Schalk led the early development of the camera control system, and SCIPP’s Al Eisner continues actively working on the system’s software. Since then, UC Santa Cruz faculty including Professors Ritz, Tesla Jeltema, Brant Robertson, Connie Rockosi, Ryan Foley, and Robert Johnson have contributed in areas ranging from project governance and software to dark energy science, galaxy evolution, and supernova research.
Deep ties and deeper involvement
Ritz, Jeltema, and Robertson are actively involved in the commissioning phase, and UC Santa Cruz’s involvement spans both the scientific collaborations and technical development, including student contributions and alumni working on the project today. Additional campus ties include Vera Rubin’s early collaboration with renowned UC Santa Cruz astrophysicist Sandra Faber, and Professor Enrico Ramirez-Ruiz holding the Vera Rubin Presidential Chair in Astronomy and Astrophysics.
In addition, one of Rubin’s sons, David Rubin, is a geologist who worked for many years in the UC Santa Cruz’s Earth and Planetary Sciences Department.
The LSST Dark Energy Science Collaboration was founded around the time that Jeltema started her faculty position at UC Santa Cruz and has since grown to over 1,300 scientists in more than 20 countries, she explained. “At the same time, UC Santa Cruz contributions have grown and deepened with additional faculty, current and former students, and close connections with UCSC colleagues working on complimentary surveys like DESI,” Jeltema said. “Now I get to see UCSC alumni at Rubin and DESC meetings making key contributions.”
Jeltema, a physics professor at SCIPP, has been a DESC member since its inception in 2012 and is active in the Clusters Working Group, the Dark Matter Working Group, and the Strong Lensing Topical Team. She became a full DESC member in 2021 and has served as its Deputy Spokesperson and on the Operations Committee since 2023.
“It has been a privilege to be part of DESC leadership in this period to support and be part of the wide-ranging science of so many and to be part of Rubin commissioning,” Jeltema said. “Seeing those first images has been simply thrilling.”
Overview of the observatory
Funded by the U.S. National Science Foundation and the U.S. Department of Energy’s Office of Science, the observatory promises to revolutionize cosmic exploration by advancing science in four main areas: the nature of dark matter and understanding dark energy, cataloging the solar system, exploring the changing sky, and Milky Way structure and formation.
The observatory will operate on an automated cadence, capturing an area the size of 40 full moons with each 30-second “visit” and returning to the same area of sky approximately every three nights. Over 10 years of operations, around 800 hundred deep exposures will be acquired for every part of the accessible sky.
As Rubin takes new images, its cutting-edge software automatically compares these new images to a template made from previous images. When a change is detected Rubin will issue an alert within minutes, available to anyone in the world. With the help of these alerts, scientists will be able to observe exploding stars before they fade away, identify millions of faint asteroids and comets we’ve never seen before, and address all kinds of brand new mysteries.
The observatory will even be able to detect nearby asteroids that could impact Earth. Rubin’s combination of speed, wide field of view, and sensitive camera expands the limits of what a telescope can do. No other telescope has been able to detect both real-time changes in the sky and faint or distant objects at the same time on this enormous scale. These capabilities mean that exceedingly rare events in the sky, never detected before, will be captured for the first time.
Vera Rubin’s legacy
The observatory’s namesake, Vera C. Rubin, was a pioneering American astronomer best known for her groundbreaking work on dark matter. In the 1970s, she and her colleague Kent Ford discovered that stars at the edges of galaxies are not moving slower with increasing distance from the center—a phenomenon that couldn’t be explained on the basis of the visible matter alone.
This led to the revolutionary conclusion that a large portion of the universe is made up of dark matter, an invisible substance that, as far as we know, interacts with the matter we can observe only by gravity. By providing the first convincing evidence of the existence of dark matter, Rubin influenced the creation of a whole new subfield of astrophysics.
Faber had just earned her undergraduate degree in physics from Swarthmore College in 1966 when she worked for the summer under Rubin and Ford at the Department of Terrestrial Magnetism (DTM) in Washington, D.C. Together, they developed detector systems that revolutionized the field. Then two years later, Faber returned to Washington to finish her Harvard Ph.D. work at DTM, where she secured a letter of recommendation from Rubin urging Lick Observatory to offer the young scientist a job.
“You must hire Sandra Faber. She will be director of the observatory one day,” Rubin stated in the letter. Faber joined Lick as an assistant professor and astronomer in 1972, tenuring in 1979, serving as interim director of UC Observatories years later, and ultimately receiving a National Medal of Science from President Barack Obama in 2013 for her deeply impactful research on the evolution of galaxies.
Faber, now an emeritus professor and astrophysicist, said she benefited greatly from seeing Rubin achieve so much in her field at a time when science was dominated by men. She recalled how dedicated Rubin was to her family and her career, to scientific accuracy, and thoughtfulness with her words. All of those strengths made her an extremely effective advocate for increasing the number of women in science.
“She had a real knack for putting in the knife and making you laugh as she turned it. She was constantly pursuing the cause of women of science, and that skill was instrumental in that effort,” Faber said. “She was not a whiner.”
Faber was the first woman to join Lick’s scientific staff, and the Rubin Observatory is the nation’s first observatory to be named after a woman.
The Rubin Observatory has an online gallery with the images and videos shown at the First Look event.
