"""SDO Map subclass definitions"""
import numpy as np
import astropy.units as u
from astropy.coordinates import CartesianRepresentation, HeliocentricMeanEcliptic
from astropy.visualization import AsinhStretch
from astropy.visualization.mpl_normalize import ImageNormalize
from sunpy.map.mapbase import GenericMap, SpatialPair
from sunpy.map.sources.source_type import source_stretch
__all__ = ['AIAMap', 'HMIMap', 'HMISynopticMap']
[docs]
class AIAMap(GenericMap):
"""AIA Image Map.
The Atmospheric Imaging Assembly is a set of four telescopes that employ
normal-incidence, multi-layer coated optics to provide narrow-band imaging
of the Sun. It provides high resolution full-disk images of the corona and
transition region up to 0.5 solar radii above the solar limb with 1.5
arcsecond angular resolution and 12-second temporal resolution. It observes
the Sun in the following seven extreme ultraviolet bandpasses: 94 A
(Fe XVIII), 131 A (Fe VIII, XXI), 171 A (Fe IX), 193 A (Fe XII, XXIV),
211 A (Fe XIV), 304 A (He II), 335 A (Fe XVI). One telescope observes
in the visible 1600 A (C IV) and the nearby continuum (1700 A).
Notes
-----
Observer location: The standard AIA FITS header provides the spacecraft location in multiple
coordinate systems, including Heliocentric Aries Ecliptic (HAE) and Heliographic Stonyhurst
(HGS). SunPy uses the provided HAE coordinates due to accuracy concerns with the provided
HGS coordinates, but other software packages may make different choices.
References
----------
* `SDO Mission Page <https://sdo.gsfc.nasa.gov/>`_
* `Instrument Page <https://aia.lmsal.com>`_
* `Fits Header keywords <http://jsoc.stanford.edu/doc/keywords/AIA/AIA02840_A_AIA-SDO_FITS_Keyword_Documents.pdf>`_
* `Analysis Guide <https://www.lmsal.com/sdodocs/doc/dcur/SDOD0060.zip/zip/entry/>`_
* `Instrument Paper <https://doi.org/10.1007/s11207-011-9776-8>`_
* `wavelengths and temperature response reference <https://www.lmsal.com/sdodocs/doc/dcur/SDOD0060.zip/zip/entry/figures/aia_tel_resp.png>`_
"""
def __init__(self, data, header, **kwargs):
super().__init__(data, header, **kwargs)
# Fill in some missing info
self._nickname = self.detector
self.plot_settings['cmap'] = self._get_cmap_name()
self.plot_settings['norm'] = ImageNormalize(
stretch=source_stretch(self.meta, AsinhStretch(0.01)), clip=False)
@property
def _supported_observer_coordinates(self):
return [(('haex_obs', 'haey_obs', 'haez_obs'), {'x': self.meta.get('haex_obs'),
'y': self.meta.get('haey_obs'),
'z': self.meta.get('haez_obs'),
'unit': u.m,
'representation_type': CartesianRepresentation,
'frame': HeliocentricMeanEcliptic})
] + super()._supported_observer_coordinates
@property
def observatory(self):
"""
Returns the observatory.
"""
return self.meta.get('telescop', '').split('/')[0]
@property
def detector(self):
return self.meta.get("detector", "AIA")
@property
def unit(self):
unit_str = self.meta.get('bunit', self.meta.get('pixlunit'))
if unit_str is None:
return
return self._parse_fits_unit(unit_str)
[docs]
@classmethod
def is_datasource_for(cls, data, header, **kwargs):
"""Determines if header corresponds to an AIA image"""
return str(header.get('instrume', '')).startswith('AIA')
[docs]
class HMIMap(GenericMap):
"""HMI Image Map.
HMI consists of a refracting telescope, a polarization selector,
an image stabilization system, a narrow band tunable filter
and two 4096 pixel CCD cameras. It observes the full solar disk in the Fe I
absorption line at 6173 Angstrom with a resolution of 1 arc-second.
HMI takes images in a sequence of tuning and polarizations at a 4-second
cadence for each camera. One camera is dedicated to a 45 s Doppler and
line-of-sight field sequence while the other to a 90 s vector field
sequence.
References
----------
* `SDO Mission Page <https://sdo.gsfc.nasa.gov/>`_
* `Instrument Page <http://hmi.stanford.edu>`_
* `Analysis Guide <http://hmi.stanford.edu/doc/magnetic/guide.pdf>`_
"""
def __init__(self, data, header, **kwargs):
super().__init__(data, header, **kwargs)
if self.unit is not None and self.unit.is_equivalent(u.T):
# Avoid JP2K images not having a norm due to UNIT8 data
# This means they are not scaled correctly.
if self.plot_settings.get('norm') is not None:
# Magnetic field maps, not intensity maps
self._set_symmetric_vmin_vmax()
self._nickname = self.detector
@property
def measurement(self):
"""
Returns the measurement type.
"""
return self.meta.get('content', '').split(" ")[0].lower()
@property
def observatory(self):
"""
Returns the observatory.
"""
return self.meta.get('telescop', '').split('/')[0]
@property
def detector(self):
return self.meta.get("detector", "HMI")
[docs]
@classmethod
def is_datasource_for(cls, data, header, **kwargs):
"""Determines if header corresponds to an HMI image"""
return (str(header.get('INSTRUME', '')).startswith('HMI') and
not HMISynopticMap.is_datasource_for(data, header))
[docs]
class HMISynopticMap(HMIMap):
"""
SDO/HMI Synoptic Map.
Synoptic maps are constructed from HMI 720s line-of-sight magnetograms
collected over a 27-day solar rotation.
See `~sunpy.map.sources.sdo.HMIMap` for information on the HMI instrument.
References
----------
* `SDO Mission Page <https://sdo.gsfc.nasa.gov/>`__
* `JSOC's HMI Synoptic Charts <http://jsoc.stanford.edu/HMI/LOS_Synoptic_charts.html>`__
"""
def __init__(self, data, header, **kwargs):
super().__init__(data, header, **kwargs)
self.plot_settings['cmap'] = 'hmimag'
self.plot_settings['norm'] = ImageNormalize(vmin=-1.5e3, vmax=1.5e3)
@property
def spatial_units(self):
cunit1 = self.meta['cunit1']
if cunit1 == 'Degree':
cunit1 = 'deg'
cunit2 = self.meta['cunit2']
if cunit2 == 'Sine Latitude':
cunit2 = 'deg'
return SpatialPair(u.Unit(cunit1), u.Unit(cunit2))
@property
def scale(self):
if self.meta['cunit2'] == 'Sine Latitude':
# Since, this map uses the cylindrical equal-area (CEA) projection,
# the spacing should be modified to 180/pi times the original value
# Reference: Section 5.5, Thompson 2006
return SpatialPair(np.abs(self.meta['cdelt1']) * self.spatial_units[0] / u.pixel,
180 / np.pi * self.meta['cdelt2'] * u.deg / u.pixel)
return super().scale
@property
def date(self):
"""
Image observation time.
This is taken from the 'DATE-OBS' or 'T_OBS' keywords.
"""
date = self._get_date('DATE-OBS')
if date is None:
return self._get_date('T_OBS')
else:
return date
@property
def unit(self):
unit_str = self.meta.get('bunit', None)
if unit_str is None:
return
# Maxwells aren't in the IAU unit style manual and therefore not a valid FITS unit
# The mapbase unit property forces this validation, so we must override it to prevent it.
return u.Unit(unit_str)
[docs]
@classmethod
def is_datasource_for(cls, data, header, **kwargs):
"""
Determines if header corresponds to an HMI synoptic map.
"""
return str(header.get('TELESCOP', '')).endswith('HMI') and 'carrington synoptic chart' in str(header.get('CONTENT', '')).lower()
