Nothing lasts forever, even galaxies, and maybe even universes.

The James Webb Space Telescope has just observed the oldest dead galaxy, that is, one in which the birth of new stars has ceased. This galaxy, poetically named RUBIES-UDS-QG-z7, ceased producing stars a mere 700 million years after the Big Bang.

Our galaxy, the Milky Way, formed some 13.6 billion years ago, some 200 million years after the Big Bang, and is still vigorously forming new stars.

The key substance driving the formation of stars, galaxies and ultimately planets and life, is hydrogen. When the universe cooled, it was made up almost entirely of hydrogen. In the young universe something stirred up the hydrogen clouds so they collapsed to form galaxies, and within those galaxies, they further collapsed to form stars.

Nuclear fusion in the cores of those stars produced energy and the first starlight, and, as waste products, all the other elements needed for making planets and living things. As........

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