""" ============================================= Reproducing the "Where is STEREO Today?" plot ============================================= How to reproduce the "Where is STEREO Today?" plot. This example uses capabilities in sunpy to reproduce the plot that can be found at ``__. This example is not written as a tutorial, but there are related tutorials for learning about these capabilities: * :ref:`sphx_glr_generated_gallery_units_and_coordinates_planet_locations.py` * :ref:`sphx_glr_generated_gallery_units_and_coordinates_ParkerSolarProbe_trajectory.py` """ import matplotlib as mpl import matplotlib.pyplot as plt import numpy as np from matplotlib.ticker import MultipleLocator import astropy.units as u from astropy.coordinates import Longitude from sunpy.coordinates import HeliocentricEarthEcliptic, get_body_heliographic_stonyhurst, get_horizons_coord from sunpy.time import parse_time ############################################################################## # Define the time for the plot as the time when this script is run. # This time is fixed as the ephemeris information for STEREO-B is no longer generated obstime = parse_time('2024-Oct-17 20:23') ############################################################################## # Define a convenience function to extract the first full orbit from a # trajectory, assuming that the trajectory moves in the direction of positive # ecliptic longitude. hee_frame = HeliocentricEarthEcliptic(obstime=obstime) def get_first_orbit(coord): lon = coord.transform_to(hee_frame).spherical.lon shifted = Longitude(lon - lon[0]) ends = np.flatnonzero(np.diff(shifted) < 0) if ends.size > 0: return coord[:ends[0]] return coord ############################################################################## # Obtain the locations and trajectories of the various planets and spacecraft. # To ensure that each trajectory contains at least one full orbit, we request # 700 days for each planet and 1 year for each spacecraft. planets = ['Mercury', 'Venus', 'Earth', 'Mars'] times = obstime + np.arange(700) * u.day planet_coords = {planet: get_first_orbit(get_body_heliographic_stonyhurst(planet, times)) for planet in planets} stereo_a = get_horizons_coord('STEREO-A', obstime) stereo_b = get_horizons_coord('STEREO-B', obstime) missions = ['Parker Solar Probe', 'Solar Orbiter', 'BepiColombo'] mission_labels = {'Parker Solar Probe': 'PSP', 'Solar Orbiter': 'SO', 'BepiColombo': 'BEPICOLOMBO'} mission_coords = {mission: get_first_orbit(get_horizons_coord(mission, {'start': obstime, 'stop': obstime + 1 * u.yr, 'step': '1d'})) for mission in missions} ############################################################################## # Define a convenience function for converting coordinates to plot positions # in the ecliptic plane. def coord_to_heexy(coord): coord = coord.transform_to(hee_frame) coord.representation_type = 'cartesian' return coord.y.to_value('AU'), coord.x.to_value('AU') ############################################################################## # Set Matplotlib settings to the desired appearance and initialize the axes. mpl.rcParams.update({'figure.facecolor': 'black', 'axes.edgecolor': 'white', 'axes.facecolor': 'black', 'axes.labelcolor': 'white', 'axes.titlecolor': 'white', 'lines.linewidth': 1, 'xtick.color': 'white', 'xtick.direction': 'in', 'xtick.top': True, 'ytick.color': 'white', 'ytick.direction': 'in', 'ytick.right': True}) fig = plt.figure() ax = fig.add_subplot() ax.set_xlim(-2.15, 2.15) ax.set_xlabel('Y (HEE)') ax.xaxis.set_major_locator(MultipleLocator(1)) ax.xaxis.set_minor_locator(MultipleLocator(0.1)) ax.set_ylim(1.8, -1.8) ax.set_ylabel('X (HEE)') ax.yaxis.set_major_locator(MultipleLocator(1)) ax.yaxis.set_minor_locator(MultipleLocator(0.1)) ax.set_title(obstime.strftime('%d-%b-%Y %H:%M UT')) ax.set_aspect('equal') # sphinx_gallery_defer_figures ############################################################################## # Draw the Sun-Earth line. ax.plot([0, 0], [0, 2], linestyle='dotted', color='gray') # sphinx_gallery_defer_figures ############################################################################## # Draw Mercury, Venus, Earth, and Mars, with Earth formatted differently. for planet, coord in planet_coords.items(): ax.plot(*coord_to_heexy(coord), linestyle='dashed', color='gray') if planet == 'Earth': color, markersize, offset = 'lime', 10, 0.1 else: color, markersize, offset = 'gray', None, 0.05 x, y = coord_to_heexy(coord[0]) ax.plot(x, y, 'o', markersize=markersize, color=color) ax.text(x + offset, y, planet, color=color) # sphinx_gallery_defer_figures ############################################################################## # Draw the STEREO spacecraft (without orbits), as well as Sun-STEREO lines. for stereo, label, color in [(stereo_a, 'A', 'red'), (stereo_b, 'B', 'blue')]: x, y = coord_to_heexy(stereo) ax.plot([0, 5*x], [0, 5*y], linestyle='dotted', color='gray') ax.plot(x, y, 'o', color=color) ax.text(x + 0.1, y, label, color=color, fontsize=18) # sphinx_gallery_defer_figures ############################################################################## # Draw the Sun, which is at the origin by definition. ax.plot(0, 0, 'o', markersize=15, color='yellow') ax.text(0.12, 0, 'Sun', color='yellow') # sphinx_gallery_defer_figures ############################################################################## # Finally, draw the various spacecraft, with Solar Orbiter colored differently. for mission, coord in mission_coords.items(): color = 'magenta' if mission == 'Solar Orbiter' else 'orange' ax.plot(*coord_to_heexy(coord), linestyle='dashed', color=color) x, y = coord_to_heexy(coord[0]) ax.plot(x, y, 'o', color=color) ax.text(x + 0.05, y, mission_labels[mission], color=color) plt.show() # This is necessary to reset the Matplotlib settings after plotting for our documentation. # You don't need this in your own code. mpl.rcParams.update(mpl.rcParamsDefault) mpl.rcParams.update({'axes.titlecolor': 'black'})