Plot the trajectory of ‘Oumuamua

This will open an interactive 3d plot of the solar system with the object plotted between the specified dates.

import kete
import matplotlib.pyplot as plt
import numpy as np

Inputs

Select the object of interest, and the times to plot the trajectory

obj = kete.HorizonsProperties.fetch("'Oumuamua")
jd_start = kete.Time.from_ymd(2016, 1, 1).jd
jd_end = kete.Time.from_ymd(2018, 1, 1).jd

# Select the scale of the X/Y/Z axis
zoom = 1.2

Plot

# Sample the time from start to end in 1 day steps
jds = np.arange(jd_start, jd_end)


# Propagate the object to all of the state
obj_pos = []
earth_pos = []
earth_r = []
last_state = obj.state
for jd in jds:
    last_state = kete.propagate_two_body([last_state], jd)[0]
    obj_pos.append(last_state.pos)
    earth_pos.append(kete.spice.get_state("Earth", jd).pos)
    earth_r.append(kete.Vector(obj_pos[-1] - earth_pos[-1]).r)

# Find the time where the closest encounter with the earth
jd_center = jds[np.argmin(earth_r)]

pos = np.array([s for s in obj_pos]).T
pos_center = obj_pos[np.argmin(earth_r)]

plt.figure(dpi=200)
ax = plt.gcf().add_subplot(projection="3d")
plt.title(
    "Designation: " + obj.desig + "\n" + f"Minimum distance: {min(earth_r):.3g} AU"
)
ax.plot(pos[0], pos[1], pos[2], alpha=0.5, color="black")
ax.scatter(pos_center.x, pos_center.y, pos_center.z, s=5, color="black")
for i, planet in enumerate(["Mercury", "Venus", "Earth", "Mars", "Jupiter"]):
    states = [kete.spice.get_state(planet, jd).pos for jd in jds]
    pos = np.array(states).T
    ax.plot(pos[0], pos[1], pos[2], color=f"C{i}", alpha=0.5)
    pos = kete.spice.get_state(planet, jd_center).pos
    ax.scatter(pos.x, pos.y, pos.z, color=f"C{i}", s=5)
ax.scatter(0, 0, 0, color="red")
ax.set_xticks([-zoom, 0, zoom])
ax.set_yticks([-zoom, 0, zoom])
ax.set_zticks([-zoom, 0, zoom])
ax.set_xlim(-zoom, zoom)
ax.set_ylim(-zoom, zoom)
ax.set_zlim(-zoom, zoom)
plt.tight_layout()
plt.show()