Are astro photos that mention the ‘Galactic Core’ incorrect? I vaguely recall hearing on a podcast some time ago that the core of the Milky Way is not viewable from earth in visible wavelengths because of intervening dust and gas, and what we see in the night sky is in fact the nearest spiral arm.
Yes, that’s basically true. Wikipedia says “Because of interstellar dust along the line of sight, the Galactic Center cannot be studied at visible, ultraviolet or soft X-ray wavelengths.” And about Sagittarius A* (the black hole at the center of the galaxy), it says “Astronomers have been unable to observe Sgr A* in the optical spectrum because of the effect of 25 magnitudes of extinction by dust and gas between the source and Earth.”
At least one of those photos seems to have an arrow indicating the ***position ***of the core. I don’t think they were implying that you were seeing the core itself.
Even if you can’t see the core proper, there’s still more stuff in that direction than in other directions, so it makes sense to call it out. Point a pair of binoculars at any old random spot in Sagittarius, and you’re likely to see some cool nebula or cluster or another.