The Universe has changed by the time you finish this sentence.

Article by:
Starts with a Bang
and
Big Think

snippet:
Let’s start with the brightest thing in our skies: the Sun. The Sun shines with a relatively constant power output — also known as its luminosity — of a humongous 3.8 × 10²⁶ Watts. The ultimate source of that power, and the reason the Sun doesn’t slowly contract, cool, and/or dim over time, is because there is a nuclear furnace burning in the Sun’s core: one that converts bare protons into helium-4 nuclei. This process, relying on several nuclear fusion chain reactions but dominated by the proton-proton chain, converts a small amount of the net initial mass of those protons, about 0.7%, into pure energy via Einstein’s most famous equation: E = mc².

This leads to a few profound changes, even over the incredibly small timescale of just three seconds or so.

First, the Sun loses mass: the equivalent of about 12 million tonnes (or 12 billion kg) over the span of reading a single sentence.

Second, the Sun very, very slowly heats up: becoming slightly more luminous (increasing its overall energy output) by a tiny factor of ~5 × 10–¹⁶.

And third, the tiny loss of mass causes the Earth to very slowly spiral outward in its orbit around the Sun: increasing our orbital radius by approximately 5 nanometers during the time it took you to read the title sentence of this article.

Just by having a Sun with the mass and energy output that it exhibits, these changes are inevitable.

https://open.substack.com/pub/startswithabang/p/the-universe-has-changed-by-the-time