FIRSTLIGHT - Exploring Cosmic Dawn with James Webb Space Telescope



Title: Exploring Cosmic Dawn with James Webb Space Telescope
Period: 1. 10. 2023 - 30. 9. 2028

Leading organization: University of Ljubljana, Faculty of Mathematics and Physics
Principal investigator: Maruša Bradač
Research activity: Universe Sciences

Project description:

The cosmic dark ages - when the Universe was filled with neutral hydrogen that was opaque to ultraviolet light - are thought to have ended around one billion years after the Big Bang, when first light sources produced enough energetic photons to ionize the neutral hydrogen. This phase is referred to as the epoch of reionization and is also the era of the first galaxies' formation. However, this is also one of the least understood epochs in the Universe's evolution. When did it start/end? Was it patchy or smooth? How did galaxies reionize the Universe (if they did)? What are the properties of the earliest galaxies?

To answer these questions, this proposal will use deep observations of the largest sample of the most powerful cosmic telescopes that will be observed with the James Webb Space Telescope (JWST) right after its launch. Compared to all previous facilities, JWST’s capabilities are dazzling. Its instruments will provide data beyond those yet seen by any astronomer.

This proposal will (1) determine the timeline of reionization, (2) identify the exact role first galaxies played in this process by studying their ionized bubbles, and (3) determine stellar properties of the earliest galaxies. With an unprecedented facility, the program will undoubtedly bring many exciting discoveries and allow the first look at the details of the Cosmic Dawn.