Jon J Thaler

Professor Emeritus


Jon J Thaler

Primary Research Area

  • Astrophysics / Relativity / Cosmology
427 Loomis Laboratory


Professor Jon Thaler received his Ph.D. in physics from Columbia University in 1972. After serving as an instructor and assistant professor at Princeton University (1972-1977), he joined the physics faculty at Illinois in 1977. For many years, professor Thaler's research activities were focused on experimental high energy physics and particle physics, determining the properties of quarks, both in their role as constituents of nuclear matter and as isolated elementary particles. He is an expert on the construction of fast trigger systems—the electronics that determines when data should be recorded—for high energy physics detectors. His contributions to the development of hardware and software systems for large collider detectors were recognized by his elevation to Fellow of the American Physical Society.

In 2003, Professor Thaler changed his research focus to astrophysics, motivated by the increasingly close connection between paricle physics ("inner space) and cosmology ("outer space). He no longer works at particle accelerators; instead, he measures particle properties using astronomical methods. He is a member of both the Dark Energy Survey (DES) and Large Synoptic Survey Telescope (LSST) collaborations. Both plan to use gigapixel-scale digital cameras on 4- and 8-meter telescopes, respectively, to survey the evolution of the universe over the last 12 billion years. This study will increase our knowledge of the dark matter and dark energy, which together make up 96% of the content of the universe.

Professor Thaler is also a concerned and gifted teacher. He created a new course, Physics 100, which is designed to address the dual problems of inadequate secondary-school preparation for some freshman students and the recruitment and retention of underrepresented groups in science, engineering, and mathematics curricula. Professor Thaler's primary objective in developing Physics 100 was to provide underprepared and underrepresented students with the skills and self-confidence needed for success in the physical sciences and engineering by integrating state-of-the-art educational technologies with innovative pedagogy and by providing core knowledge in traditional physics topics. Corollary objectives were to provide student opportunities for leadership in collaborative projects, to create a culture of intellectual enquiry by providing a range of experiences that promote critical and analytical thinking, and to disseminate our curriculum to physics teachers in secondary schools, community colleges, and peer universities.

More recently, professor Thaler chaired a committee that reorganized the undergraduate Physics major's curriculum.  The two goals were:  1) to expose Physics majors to interesting and challenging material (e.g., special relativity) early in their career, both to increase their motivation and to ease the transition to the advanced coursework; and 2) to make room for fluids and continuous media in the intermediate mechanics course.  Continuous media (e.g., fluids) are not only important in their own right, but also provide a conceptual framework in which to think about field theory in general, from classical electrodynamics to quantum mechanics.

Research Statement

Dark Energy Survey (DES)
This project built a new 500-megapixel CCD camera for the 4-m Blanco telesctop at CTIO in Chile. We will use it to study supernovas and the time development of large scale structure (the distribution of galaxies and clusters of galaxies). These measurements will begin to constrain the properties of the dark energy, possibly testing whether or not it is Einstein's cosmological constant. We wil begin collecting data in 2013.

Large Synoptic Survey Telescope (LSST)
We will build a new 8.4-m telescope optimized for cosmological studies. Beginning in about 2019, we will survey half of the sky, mapping the time development of structure formation during the past 12 billion years. We will also observe more than a million supernovas. This enormous data set will yield precise measurements of the properties of dark matter and dark energy and may also allow us to make the first measurement of the mass of the neutrino.


  • Fellow of the American Physical Society, 1998 (1998)

Related news

  • Research
  • Astrophysics
  • Astrophysics/Cosmology

A team of scientists using the Dark Energy Camera (DECam), the primary observing tool of the Dark Energy Survey (DES), was among the first to observe the fiery aftermath of a recently detected burst of gravitational waves, recording images of the first confirmed explosion from two colliding neutron stars ever seen by astronomers.

Scientists on the DES joined forces with a team of astronomers based at the Harvard-Smithsonian Center for Astrophysics (CfA) for this effort, working with observatories around the world to bolster the original data from DECam. Images taken with DECam captured the flaring-up and fading over time of a kilonova – an explosion similar to a supernova, but on a smaller scale – that occurs when collapsed stars (called neutron stars) crash into each other, creating heavy radioactive elements.

Two scientists at the University of Illinois at Urbana-Champaign are members of the DES collaboration, Professors Joaquin Vieira of the Departments of Astronomy and of Physics and Felipe Menanteau of the Department

  • Research
  • Astrophysics/Cosmology

Scientists on the Dark Energy Survey have released the first in a series of dark matter maps of the cosmos. These maps, created with one of the world’s most powerful digital cameras, are the largest contiguous maps created at this level of detail and will improve our understanding of dark matter’s role in the formation of galaxies. Analysis of the clumpiness of the dark matter in the maps will also allow scientists to probe the nature of the mysterious dark energy, believed to be causing the expansion of the universe to speed up.

The new map was released today at the April meeting of the American Physical Society in Baltimore, Maryland. It was created using data captured by the Dark Energy Camera, a 570-megapixel imaging device that is the primary instrument for the Dark Energy Survey (DES).

  • Research
  • Astrophysics/Cosmology
  • Astrophysics
  • Cosmology

Scientists on two continents have independently discovered a set of celestial objects that seem to belong to the rare category of dwarf satellite galaxies orbiting our home galaxy, the Milky Way.

Dwarf galaxies are the smallest known galaxies, and they could hold the key to understanding dark matter, and the process by which larger galaxies form.

A team of researchers with the Dark Energy Survey, headquartered at the U.S. Department of Energy’s Fermi National Accelerator Laboratory, and an independent group from the University of Cambridge  jointly announced their findings today. Both teams used data taken during the first year of the Dark Energy Survey, all of which is publicly available, to carry out their analysis.