Look up!! Studying Our Universe Using Telescopes and Simulations

Stars in the night sky display a stunning variety of colors from crimson red to ice blue. Magnificence of the cosmic palette is hard to miss in photographs of deep space. It is however less obvious that star colors also have scientific value: they encode temperatures, ages, masses and chemical compositions of stars. The new generation of telescopes has allowed astronomers to “read” this cosmic color code with unprecedented clarity. In this talk, I will share what we learned about the oldest stars and planets in our Galaxy from the colors of stars revealed by the James Webb Space Telescope.

Cosmology is the study of the whole universe and its history, and how an ultra-hot beginning became the millions of galaxies we see today. Matter fell into dense clusters, filaments, and walls and ignited, creating a cosmic web of galaxies, but the structure of that web and light from before stars reveals 'dark' ingredients. Simulations of the whole cosmos let Notre Dame scientists compare ideas with reality and show a beautiful universe forming before our eyes. Prof. Davis will show images from simulations of the cosmos, and explain the questions they address.