Others have already answered the actual question ...

But in part, because I'm a bit of a file-formats snob, and in part because I've been dealing with an e-mail discussion for the last month or so on trying to come up with standards on describing these sort of text files as used in space physics for time tagged data for event lists (vs. time series at a fixed cadence) ... as you mention you're in the astronomy field, have you considered spitting out VOTable? None of the perl libraries comply with the 1.2 spec unfortunately (and only the version in Astro::Catalog is actually in CPAN), but you should then be able to hand off the plotting work to dedicated tools like VOPlot (docs/examples).

(and I say this *only* because you're in astronomy; if you were in earth sciences, I'd recommend HDF; CDF for space physics; NetCDF for storage for atmospheric sciences (with an OPeNDAP service for distribution). There's also Google's Dataset Publishing Language to document CSV files so that some of Google's tools can be used to visualize them, and there's lots of other standards out there for all of the various javascript visualization tools.