HOWTO open planetary data products

planetarypy can open a planetary data product into memory with a single call — no need to know the product’s format or hand-roll a reader.

import planetarypy

d = planetarypy.open("P02_001916_2221_XI_42N027W.LBL")

The right thing happens automatically based on what the file is.

One call to open anything

For most products (PDS3 .IMG/.LBL, PDS4, FITS, …) open returns a dict-like handle. You reach the contained objects by key, and the label metadata via metaget:

d.keys()                 # e.g. ['LABEL', 'IMAGE']
arr = d["IMAGE"]         # a numpy array
df  = d["INDEX_TABLE"]   # a pandas DataFrame (for TABLE objects)
d.metaget("LINES")       # read a value from the label

For detached-label PDS3 products, pass the label (.LBL) — it is the correct entry point and tells the reader where the data file lives.

Download and open in one step

If you are fetching from the catalog, you don’t need an intermediate path variable. Either call .open() on the result, or pass open=True:

from planetarypy.catalog import fetch_product

# Option A — open the result:
d = fetch_product("mro.ctx.edr", "P02_001916_2221_XI_42N027W").open()

# Option B — fetch and open in one call:
d = fetch_product("mro.ctx.edr", "P02_001916_2221_XI_42N027W", open=True)

.open() opens the label when one was downloaded, otherwise the single downloaded data file. If a product wrote several data files, it raises and asks you to call planetarypy.open(path) on the specific file you want.

Projected rasters come back georeferenced

GeoTIFFs and ISIS .cub files are already map-projected, so open returns a georeferenced xarray.DataArray (via rioxarray) instead of the generic handle — you keep the CRS and coordinates:

da = planetarypy.open("mosaic.tif")   # xarray.DataArray with x/y coords
da.rio.crs

You can override the routing with the projected keyword when the suffix isn’t a reliable signal:

planetarypy.open("weird.dat", projected=False)   # force the generic reader
planetarypy.open("scene.raw", projected=True)     # force the raster reader

From the command line

plp open P02_001916_2221_XI_42N027W.LBL   # prints the contained objects
plp open mosaic.tif --show                # display the default image

Under the hood (for contributors)

The generic reader is MillionConcepts’ pdr (Planetary Data Reader), shipped as a core dependency so planetarypy.open works out of the box. Projected rasters are routed to rioxarray instead. End users never need to install or import pdr directly.