Strange radio waves emerge from direction of the galactic centre (opens in new tab)

One of the best (IMHO) Sci-Fi books "His Master's Voice" by Stanisław Lem begins exactly like this.

"It is a densely philosophical first contact story about an effort by scientists to decode, translate, and understand an extraterrestrial transmission. The novel critically approaches humanity's intelligence and intentions in deciphering and truly comprehending a message from outer space." https://en.wikipedia.org/wiki/His_Master%27s_Voice_(novel)

Source is here: https://iopscience.iop.org/article/10.3847/1538-4357/ac2360

This is a draft/pre-print version https://arxiv.org/pdf/2109.00652.pdf

earlier discussion: https://news.ycombinator.com/item?id=28840102