예제 #1
0
def plot_ang_vel(radius, incl, maxTime, dt, theta_0):
    """radius, in AU
       incl, inclination in degrees
       maxTime, max time of plot in years
       dt, time step in years
       theta_0, time 0 angle along orbit in relation to sun-Earth line.
                Note: probably would be more useful to have angle from
                opposition as viewed from Earth. Will make this change
                in future update
    """
    time_step = np.arange(0, maxTime, dt)
    lon = []
    lat = []
    for time in time_step:
        lon_now, lat_now = ct.sphericalFromCartesian(
            diff_vec(radius, np.deg2rad(incl), time, theta_0))
        lon.append(lon_now)
        lat.append(lat_now)
    lon = np.array(lon)
    lat = np.array(lat)
    ang_vel = []
    for array_val in xrange(0, len(lon) - 1):
        ang_vel.append(
            ct.arcsecFromRadians(
                ct.haversine(lon[array_val], lat[array_val],
                             lon[array_val + 1], lat[array_val + 1])) /
            (dt * 365 * 24))
    #fig = plt.figure(figsize=(12,12))
    plt.plot(time_step[:-1], ang_vel)
    plt.ylabel('Arcsec/hr')
    plt.xlabel('Time (yrs)')
    plt.title('Max Angular Velocity = %.4e arcsec/hr.' % np.max(ang_vel))
예제 #2
0
def plot_trajectory(radius, incl, maxTime, dt, theta_0):
    """radius, in AU
       incl, inclination in degrees
       maxTime, max time of plot in years
       dt, time step in years
       theta_0, time 0 angle along orbit in relation to sun-Earth line.
                Note: probably would be more useful to have angle from
                opposition as viewed from Earth. Will make this change
                in future update
    """
    time_step = np.arange(0, maxTime, dt)
    lon = []
    lat = []
    for time in time_step:
        lon_now, lat_now = ct.sphericalFromCartesian(
            diff_vec(radius, np.deg2rad(incl), time, theta_0))
        lon.append(ct.arcsecFromRadians(lon_now))
        lat.append(ct.arcsecFromRadians(lat_now))
    lon = np.array(lon)
    lat = np.array(lat)
    #fig = plt.figure(figsize=(12,12))
    plt.scatter(lon, lat, c=time_step, lw=0)
    plt.xlabel('Long (arcsec)')
    plt.ylabel('Lat (arcsec)')
    plt.title('Trajectory of object over %.2f years' % maxTime)
    plt.colorbar()
예제 #3
0
def get_ang_vel(radius, incl, dt):
    """
    radius, in AU
    incl, inclination in degrees
    dt, time step in years
    """
    time_step = np.arange(0, np.sqrt(radius**3.), dt)
    lon = []
    lat = []
    for time in time_step:
        lon_now, lat_now = ct.sphericalFromCartesian(
            diff_vec(radius, np.deg2rad(incl), time, 0.))
        lon.append(lon_now)
        lat.append(lat_now)
    lon = np.array(lon)
    lat = np.array(lat)
    ang_vel = []
    for array_val in xrange(0, len(lon) - 1):
        ang_vel.append(
            ct.arcsecFromRadians(
                ct.haversine(lon[array_val], lat[array_val],
                             lon[array_val + 1], lat[array_val + 1])) /
            (dt * 365 * 24))
    #fig = plt.figure(figsize=(12,12))
    lat_diff = lat[1:] - lat[:-1]
    lon_diff = lon[1:] - lon[:-1]
    angle_travelled = np.arctan2(lat_diff, lon_diff)
    allowed_range = np.where(np.abs(np.degrees(angle_travelled)) < 15.)

    return np.array(ang_vel), np.degrees(angle_travelled)
예제 #4
0
def plot_ang_vel(radius, incl, maxTime, dt, theta_0):
    """radius, in AU
       incl, inclination in degrees
       maxTime, max time of plot in years
       dt, time step in years
       theta_0, time 0 angle along orbit in relation to sun-Earth line.
                Note: probably would be more useful to have angle from
                opposition as viewed from Earth. Will make this change
                in future update
    """
    time_step = np.arange(0,maxTime,dt)
    lon = []
    lat = []
    for time in time_step:
        lon_now,lat_now = ct.sphericalFromCartesian(diff_vec(radius,np.deg2rad(incl),time,theta_0))
        lon.append(lon_now)
        lat.append(lat_now)
    lon = np.array(lon)
    lat = np.array(lat)
    ang_vel = []
    for array_val in xrange(0, len(lon)-1):
        ang_vel.append(ct.arcsecFromRadians(ct.haversine(lon[array_val], lat[array_val],
                                                         lon[array_val+1], lat[array_val+1]))/(dt*365*24))
    #fig = plt.figure(figsize=(12,12))
    plt.plot(time_step[:-1], ang_vel)
    plt.ylabel('Arcsec/hr')
    plt.xlabel('Time (yrs)')
    plt.title('Max Angular Velocity = %.4e arcsec/hr.' % np.max(ang_vel))
예제 #5
0
def plot_trajectory(radius, incl, maxTime, dt, theta_0):
    """radius, in AU
       incl, inclination in degrees
       maxTime, max time of plot in years
       dt, time step in years
       theta_0, time 0 angle along orbit in relation to sun-Earth line.
                Note: probably would be more useful to have angle from
                opposition as viewed from Earth. Will make this change
                in future update
    """
    time_step = np.arange(0,maxTime,dt)
    lon = []
    lat = []
    for time in time_step:
        lon_now,lat_now = ct.sphericalFromCartesian(diff_vec(radius,np.deg2rad(incl),time,theta_0))
        lon.append(ct.arcsecFromRadians(lon_now))
        lat.append(ct.arcsecFromRadians(lat_now))
    lon = np.array(lon)
    lat = np.array(lat)
    #fig = plt.figure(figsize=(12,12))
    plt.scatter(lon, lat, c=time_step, lw=0)
    plt.xlabel('Long (arcsec)')
    plt.ylabel('Lat (arcsec)')
    plt.title('Trajectory of object over %.2f years' % maxTime)
    plt.colorbar()
예제 #6
0
def get_trajectory(radius, incl, dt):
    """
    Returns longitude and latitude coordiantes of full orbit in ecliptic coordinates.
    
    radius, in AU
    incl, inclination in degrees
    dt, time step in years
    """
    time_step = np.arange(0, np.sqrt(radius**3.), dt)
    lon = []
    lat = []
    for time in time_step:
        lon_now, lat_now = ct.sphericalFromCartesian(
            diff_vec(radius, np.deg2rad(incl), time, 0.))
        lon.append(ct.arcsecFromRadians(lon_now))
        lat.append(ct.arcsecFromRadians(lat_now))
    lon = np.array(lon)
    lat = np.array(lat)

    return ct.degreesFromArcsec(lon), ct.degreesFromArcsec(lat)