BackForwardInstrument:  Pyxis-RO 

Instrument details
Acronym Pyxis-RO
Full name Pyxis-RO
Purpose Temperature/humidity sounding with highest vertical resolution, space weather
Short description Measuring the phase delay due to refraction during occultation between GPS and LEO
Background Consolidated technology
Scanning Technique Limb scanning from 600 km to close-to-surface by time sampling - Azimuth: 90° sectors fore- and aft-
Resolution About 300 km horizontal, 0.5 km vertical
Coverage / Cycle 4 GNSS constellations tracked. About 2500 soundings/day (about 50,000 soundings/day with 20 satellites) - Average spacing 450 km - Global coverage (300 km spacing) in 2.5 days.
Mass Power Data Rate

 

Providing Agency PlanetiQ
Instrument Maturity Backed by strong heritage
Utilization Period: 2020 to 2027
Last update: 2021-12-13
Detailed characteristics
Satellites this instrument is flying on

Note: a red tag indicates satellites no longer operational, a green tag indicates operational satellites, a blue tag indicates future satellites

Instrument classification
  • Earth observation instrument
  • Active and radio-occultation sensor
  • GNSS radio-occultation
WIGOS Subcomponents
  • Subcomponent 2
  • Magnetospheric energetic particles and magnetometers
  • Ionospheric total electron content sensor [at LEO and cross magnetosphere]
  • Ionospheric electron density sensor [in LEO and cross magnetosphere]
  • Subcomponent 4
  • GNSS radio occultation (commercial)
  • GNSS radio occultation constellation (commercial)
Mission objectives
Primary mission objectives
  • Atmospheric temperature
  • Height of the top of PBL
  • Height of the tropopause
  • Specific humidity
  • Temperature of the tropopause
Evaluation of Measurements

The following list indicates which measurements can typically be retrieved from this category of instrument. To see a full Gap Analysis by Variable, click on the respective variable.

Note: table can be sorted by clicking on the column headers
Note: * Primary mission objective.
VariableRelevance for measuring this variableOperational limitationsExplanation
Atmospheric temperature*1 - primaryInaccurate in low troposphere.Flown in a satellite cluster. Two directional antennas, three GNSS systems tracked, about 1500 soundings/day per satellite
Geoid4 - fairHighly indirect.Radio-occultation processing implies precise orbitography. Geoid derived from multi-temporal analysis
Gravity field5 - marginalHighly indirect.Radio-occultation processing implies precise orbitography. Gravity field derived from multi-temporal analysis
Height of the top of PBL*1 - primaryNo specific limitation.Flown in a satellite cluster. Two directional antennas, three GNSS systems tracked, about 1500 soundings/day per satellite. PBL top measured as discontinuity of the refraction index
Height of the tropopause*1 - primaryNo specific limitation.Flown in a satellite cluster. Two directional antennas, three GNSS systems tracked, about 1500 soundings/day per satellite. Tropopause height measured as discontinuity of the refraction index
Specific humidity*2 - very highInaccurate in high troposphere.Flown in a satellite cluster. Two directional antennas, three GNSS systems tracked, about 1500 soundings/day per satellite
Temperature of the tropopause*1 - primaryNo specific limitation.Flown in a satellite cluster. Two directional antennas, three GNSS systems tracked, about 1500 soundings/day per satellite
Atmospheric density1 - primaryNo specific limitation.Measuring atmospheric density
Electron Density1 - primaryNo specific limitation.Flown in a satellite cluster. Two directional antennas, three GNSS systems tracked, about 1500 soundings/day per satellite
Ionospheric Vertical Total Electron Content (VTEC)2 - very highNo specific limitation.Flown in a satellite cluster. Two directional antennas, three GNSS systems tracked, about 1500 soundings/day per satellite
Ionospheric Scintillation4 - fairNo specific limitation.Flown in a satellite cluster. Two directional antennas, three GNSS systems tracked, about 1500 soundings/day per satellite