Are Aliens Made Mostly of Oxygen?

Looking in the mirror, we might wonder where did most of our body mass come from? The answer is that it was produced by nuclear fusion reactions in the hot interiors of stars, at tens of millions of degrees. Massive stars with more than 8 solar masses exploded and ejected oxygen to interstellar space where it cooled and joined hydrogen to make water. In fact, water vapor is <a href="https://iopscience.iop.org/article/10.1088/2041-8205/804/2/L29/pdf" rel="noopener ugc nofollow" target="_blank">predicted</a> to have formed very early, as soon as the primordial gas was enriched by the first generation of stars in the earliest galaxies that the Webb telescope is <a href="https://www.space.com/james-webb-space-telescope-200-galaxies-distances-revealed" rel="noopener ugc nofollow" target="_blank">now detecting</a>. These galaxies were theorized in my decade-old textbook on “<a href="https://press.princeton.edu/books/hardcover/9780691144917/the-first-galaxies-in-the-universe" rel="noopener ugc nofollow" target="_blank">The First Galaxies in the Universe</a>”. When I arrived at Harvard thirty years ago and started working on this research frontier with my students and postdocs, there was negligible interest in this topic worldwide. In the PhD defenses of my first two students, Daniel Eisenstein and Zoltan Haiman, the examiners doubted that galaxies existed hundreds of millions of years after the Big Bang when the Universe was just a percent of its current age. <a href="https://avi-loeb.medium.com/are-aliens-made-mostly-of-oxygen-e20474d4b233">Click Here</a>