Maps

A map is represented by a Map object. We can load some pre-defined ones with

from maria.io import fetch

map_filename = fetch("maps/big_cluster.fits")

input_map = maria.map.read_fits(filename=map_filename,
                                index=1, # which index of the HDU to read
                                nu=150., # in GHz
                                resolution=1/1024,
                                center=(150, 10),
                                frame="ra_dec",
                                units="Jy/pixel")

input_map.to(units="K_RJ").plot()

Time-evolving maps

maria supports maps that evolve in time, which is useful for modeling e.g. solar observations.

time_evolving_sun_path = fetch("maps/sun.h5")
input_map = maria.map.load(filename=time_evolving_sun_path, t=1.7e9 + np.linspace(0, 180, 16))
plan = maria.Plan(start_time=1.7e9,
                  duration=180,
                  scan_center=np.degrees(input_map.center),
                  scan_options={"radius": 0.25})
sim = maria.Simulation(plan=plan, map=input_map)
tod = sim.run()
tod.plot()

Warning

If the observation overruns the start or end of the map in time, it will lead to some funky discontinuities.