empyrean.PlannedObservation¶

class PlannedObservation(epoch_mjd_tdb, kind=PlannedObservationKind.OPTICAL, optical_code='', optical_sigma_arcsec=(1.0, 1.0), radar_transmit_station=RadarStation.GOLDSTONE_DSS14, radar_receive_station=RadarStation.GOLDSTONE_DSS14, radar_mode=RadarMode.BOTH, radar_bandwidth_hz=0.0, radar_freq_resolution_hz=0.0, radar_snr=None, radar_target_h_mag=None, radar_target_visual_albedo=None, radar_target_radar_albedo=None, radar_target_diameter_km=None, radar_target_spin_period_hours=None, radar_integration_s=0.0)[source]

Bases: object

One candidate observation: when it would be taken and what it would measure.

Tagged-union shape — the active fields depend on kind, and fields belonging to the other kind must be left at their defaults. Setting an inapplicable field raises ValueError at construction rather than being silently ignored. Prefer the optical() / radar() constructors, which set the discriminator for you.

Mirrors empyrean::PlannedObservation.

Methods

`__init__`(epoch_mjd_tdb[, kind, ...])
`optical`(epoch_mjd_tdb, optical_code[, ...])	An optical candidate at a registered observatory.
`radar`(epoch_mjd_tdb, *[, ...])	A radar candidate at the given receive epoch.

Attributes

`kind`
`optical_code`	Registered MPC observatory code (e.g. `"F51"`).
`optical_sigma_arcsec`	Assumed 1σ (RA·cosδ, Dec) astrometric uncertainty in arcsec.
`radar_bandwidth_hz`	Waveform bandwidth (Hz) — sets the delay (range) σ.
`radar_freq_resolution_hz`	Doppler frequency resolution (Hz) — sets the range-rate σ.
`radar_integration_s`	Coherent integration time (s) for the link budget.
`radar_mode`	Which observable(s) to measure.
`radar_receive_station`	Receiving dish.
`radar_snr`	Effective SNR as a linear power ratio, not dB.
`radar_target_diameter_km`	Link-budget target effective diameter (km).
`radar_target_h_mag`	Link-budget target absolute magnitude $H$ (mag).
`radar_target_radar_albedo`	Link-budget target radar (OC) albedo.
`radar_target_spin_period_hours`	Link-budget target rotation period (hours); caps the coherent integration time.
`radar_target_visual_albedo`	Link-budget target visual geometric albedo $p_V$ .
`radar_transmit_station`	Transmitting dish.
`epoch_mjd_tdb`	Planned epoch (MJD TDB) — the receive epoch for radar.

Parameters:

epoch_mjd_tdb (float)
kind (PlannedObservationKind)
optical_code (str)
optical_sigma_arcsec (tuple[float, float])
radar_transmit_station (RadarStation)
radar_receive_station (RadarStation)
radar_mode (RadarMode)
radar_bandwidth_hz (float)
radar_freq_resolution_hz (float)
radar_snr (float | None)
radar_target_h_mag (float | None)
radar_target_visual_albedo (float | None)
radar_target_radar_albedo (float | None)
radar_target_diameter_km (float | None)
radar_target_spin_period_hours (float | None)
radar_integration_s (float)

epoch_mjd_tdb: float: Planned epoch (MJD TDB) — the receive epoch for radar.

kind: PlannedObservationKind = 'optical'

optical_code: str = '': Registered MPC observatory code (e.g. "F51").

optical_sigma_arcsec: tuple[float, float] = (1.0, 1.0): Assumed 1σ (RA·cosδ, Dec) astrometric uncertainty in arcsec.

radar_transmit_station: RadarStation = 'goldstone_dss14': Transmitting dish.

radar_receive_station: RadarStation = 'goldstone_dss14': Receiving dish. Equal to the transmit station = monostatic.

radar_mode: RadarMode = 'both': Which observable(s) to measure.

radar_bandwidth_hz: float = 0.0: Waveform bandwidth (Hz) — sets the delay (range) σ. Must be positive for RadarMode.DELAY or RadarMode.BOTH.

radar_freq_resolution_hz: float = 0.0: Doppler frequency resolution (Hz) — sets the range-rate σ. Must be positive for RadarMode.DOPPLER or RadarMode.BOTH.

radar_snr: float | None = None

Effective SNR as a linear power ratio, not dB.

None — the default — means derive it from the link budget over the radar_target_* properties and radar_integration_s. That is a different request, not a missing value: supply a number and the link budget is not consulted at all. Whatever the link budget had to assume comes back on PlanCandidates.radar_provenance, so a derived SNR is never silent.

radar_target_h_mag: float | None = None: Link-budget target absolute magnitude $H$ (mag). None = not known.

radar_target_visual_albedo: float | None = None: Link-budget target visual geometric albedo $p_V$ . None = not known.

radar_target_radar_albedo: float | None = None: Link-budget target radar (OC) albedo. None = not known.

radar_target_diameter_km: float | None = None: Link-budget target effective diameter (km). None = not known.

radar_target_spin_period_hours: float | None = None: Link-budget target rotation period (hours); caps the coherent integration time. None = not known.

radar_integration_s: float = 0.0: Coherent integration time (s) for the link budget. Read only when radar_snr is None.

classmethod optical(epoch_mjd_tdb, optical_code, optical_sigma_arcsec=(1.0, 1.0))[source]

An optical candidate at a registered observatory.

Mirrors empyrean::PlannedObservation::optical.

Return type:

PlannedObservation

Parameters:

epoch_mjd_tdb (float)
optical_code (str)
optical_sigma_arcsec (tuple[float, float])

classmethod radar(epoch_mjd_tdb, *, radar_transmit_station=RadarStation.GOLDSTONE_DSS14, radar_receive_station=RadarStation.GOLDSTONE_DSS14, radar_mode=RadarMode.BOTH, radar_bandwidth_hz=0.0, radar_freq_resolution_hz=0.0, radar_snr=None, radar_target_h_mag=None, radar_target_visual_albedo=None, radar_target_radar_albedo=None, radar_target_diameter_km=None, radar_target_spin_period_hours=None, radar_integration_s=0.0)[source]

A radar candidate at the given receive epoch.

Mirrors empyrean::PlannedObservation::radar. Leave radar_snr at None to have the effective SNR derived from the link budget over the radar_target_* properties and radar_integration_s.

Return type:

PlannedObservation

Parameters:

epoch_mjd_tdb (float)
radar_transmit_station (RadarStation | str)
radar_receive_station (RadarStation | str)
radar_mode (RadarMode | str)
radar_bandwidth_hz (float)
radar_freq_resolution_hz (float)
radar_snr (float | None)
radar_target_h_mag (float | None)
radar_target_visual_albedo (float | None)
radar_target_radar_albedo (float | None)
radar_target_diameter_km (float | None)
radar_target_spin_period_hours (float | None)
radar_integration_s (float)