My research focuses on exploring the most distant galaxies in detail using the combined power of the Webb and Hubble Space Telescopes and gravitational lensing. Lensing magnifies background galaxies and allows us to resolve details on smaller spatial scales than would be possible otherwise. Below are a few recent highlights from my work.
The Light of Earendel
Earendel is the most distant star that has yet been observed. It has a redshift of z = 6.2, meaning that we are seeing the light it emitted a mere 900 million years after the Big Bang. The star is extremely magnified by gravitational lensing, so the image we see appears thousands of times brighter than it otherwise would. This high magnification allows us to distinguish the light of the star from the rest of the host galaxy. Typically we can only see full galaxies at this distance, with the light of millions of stars blending together.
Images of Earendel taken by the Webb Space Telescope (left) have confirmed that this is a stellar object. The images suggest that Earendel is either a single, evolved B-type giant star, or perhaps a binary consisting of one relatively hot (30,000 K) and one cooler (10,000 K) star. (JWST Earendel Paper)