{"@type": "dcat:Dataset", "accessLevel": "public", "accrualPeriodicity": "irregular", "bureauCode": ["026:00"], "contactPoint": {"@type": "vcard:Contact", "fn": "Thomas Morgan", "hasEmail": "mailto:thomas.h.morgan@nasa.gov"}, "description": "The instrument has detected superthermal, energetic\nor fast ions whose energy exceeds 36 eV in the spacecraft\nframe of reference.  These ions were observed in early orbits\nduring measurements of the neutral density near periapsis, have\nan erratic and unpredictable signature, and occur at too high an\naltitude to be due to the neutral atmosphere. When the altitude\nof periapsis increased above the point where sensible neutral\ndensity measurements could be made, the instrument was configured\nspecifically to detect superthermal ions.  In general, for orbit\nnumbers 1 to 645, data were taken from the RPA mode.  The gas\nbackground signal with the filament on is about a factor of 10\nless in this mode than in non-RPA mode, resulting in a lower\ndetection threshold. For orbit numbers above 923, the instrument\nwas deliberately configured with the filament off and non-RPA\nmode data was used. For mass 16 the RPA voltage is about +3.8\nvolts.", "identifier": "urn:nasa:pds:context_pds3:data_set:data_set.pvo-v-onms-4-superthrmloxygn-12sec-v1.0_9tu7-enqb", "issued": "2021-05-21", "keyword": ["pioneer-venus", "venus"], "landingPage": "https://pds.nasa.gov/ds-view/pds/viewDataset.jsp?dsid=PVO-V-ONMS-4-SUPERTHRMLOXYGN-12SEC-V1.0", "license": "http://www.usa.gov/publicdomain/label/1.0/", "modified": "2025-07-17", "programCode": ["026:005"], "publisher": {"@type": "org:Organization", "name": "National Aeronautics and Space Administration"}, "references": ["https://pds.nasa.gov"], "theme": ["Earth Science"], "title": "PVO VENUS ONMS BROWSE SUPERTHERMAL\n                                      OXYGEN 12 SECOND V1.0"}