This is just me asking, but if the universe were expanding wouldn’t the twelve Constellations get all out of whack instead of remaining at the very same configurations as they were 2 or 3 millennia ago?
The constellations do change over time. But not due to universal expansion, but rather because, like everything in the the universe, the stars are in motion. We can’t notice any changes during the course of our lifetimes, as it takes thousands of years to become noticeable.
No.
The stars in the constellations are in our galaxy, practically next door. And given time they will in fact move from their present positions and scramble the constellations. A couple thousand years is a link of the cosmic eye....
Galaxies are mostly moving apart, except our huge neighbor Andromeda which is on a collision course with our Milky Way galaxy. The collision is about 3 billion years away.
The constellations we can see with our bare eyes are all nearby stars in the Milky Way and are orbiting the massive black hole in the center of the galaxy so they are moving along with us. The stars in the Milky Way are not moving apart, they are slowly being sucked into the black hole. Generally it is other galaxies that are moving away from us (except for Andromeda).
We can’t actually “see” any stars, except our sun. What we see are point sources of photons emitted by other suns. If it weren’t for the emitted photons the stars would be undetectable.
If they were objects illuminated by reflected light only, we could never detect or resolve the very tiny angular diameters of suns hundreds or thousands of light years distant.
All this is to establish that while all stars are in motion, the distances involved are so staggeringly vast that it takes thousands of years for them to change relative positions in our sky to a detectable extent.
Is this Cold Fusion??
Point of information: There are 88 constellations, 12 of which on the ecliptic (the projection of earth's orbital plane onto the sky) make up the Zodiac. The Zodiac is important to astrology because the orbits of the other planets are confined to stay within it. The ancient Babylonians charted the position of the sun against the Zodiac by noting the position of the moon among the stars during a lunar eclipse, and correctly assigning the sun the opposite position.
Your zodiacal sign roughly corresponds to the position of the sun along the zodiac on the calendar date of your birth at the time that the Julian calendar was adopted. The dates of the location of the actual sun have changed by about a month earlier due to precession of the equinoxes, a phenomenon apparently unrecognized by the Babylonians, but completely familiar to Greek astronomers.
When things are thousand/millions of light years away, a lot of motion is next to imperceptible over a few thousand year time-frame.
Saw this article a while back. Yes they change.
https://spaceplace.nasa.gov/review/dr-marc-space/constellations.html