when did hipparchus invent the planispheric astrolabe?

Question

im doing a research project about hipparchus but cannot find when he invented the planispheric astrolabe, and cannot also find when he was born and when he died

Answer 1

Hipparcos lived ca. 190 BC – ca. 120 BC. Nobody knows exactly what year he invented it, or if it was even him. Some credit its invention to Hypatia.

Answer 2

Hipparchos is not credited with inventing the planispheric astrolabe, but he probably used the armillary astrolabe, also known as the armillary sphere or astrolabon.

It seems likely that Hipparchos used a wide variety of sky measuring tools during his career, and may have improved on the kind of tools in practice. But we cannot say for sure what, if anything, he actually invented.

We also do not know his birth or death dates, although the previous estimate of 190 - 120 BC is about right. He was born in Nicea, in Asia Minor, and died in Rhodes.