It takes on a new importance given developments

It takes on a new importance given developments since the Galileo flyby. In 1990, no planets orbiting stars other than the Sun were known.

Source: Nature

Does "given" here mean "considering"? It's also likely that it means "assumed as a premise". I am not sure.
What does it mean?

Yes, 'considering' is a decent synonym here. Or 'in the light of' or 'taking into account'.

I don't know what you mean by 'assumed as a premise'. What premise?

Much more interesting to me is that they hadn't discovered any exo-planets at that point, but since then they have discovered quite a few.