I stumbled upon this map that allegedly shows Chinese explorer Zeng He discovered America before 1418. However, I haven't been able to find any recent developments. Was the map ever authenticated? Were there any more pieces of evidence discovered? It seems odd that most of the articles I've seen date to 2006 or earlier.
Hello! This is actually a part of our FAQ. You can find several pertinent answers here.
On a related note, the specific map you post appears to be an 18th century copy which only claims to be based on an early 15th century original, according to National Geographic. The map appears to be a fake.