A dataset provided by the European Space Agency

URL ftp://npsa01.esac.esa.int/pub/mirror/VENUS-EXPRESS/ASPERA4/VEX-V-SW-ASPERA-2-EXT4-NPD-V1.0
DOI https://doi.org/10.5270/esa-39tzigv
Abstract This data set contains Venus Express ASPERA-4 Neutral Particle Detector (NPD) data that have been acquired during the extended mission phase 4. The data are provided in raw units of counts/accumulation.
Description Data Set Overview: This data set contains data collected by the Neutral Particle Detector (NPD) flown onboard the VENUS EXPRESS satellite during the extended mission phase 4. The data are stored in ascending time order with respect to the sequential in-flight data acquisition. The data (science and HK) in this archive are in standard PDS format and are both organized into fixed-width tabular objects, an ASCII format with data store in rows and columns. Mainly 3 types of science data are present, one for each selected operation mode. Depending on the flight operation mode in use, science data records are either a data stream of observations identified by a quadruplet (Pulse Height Distribution, Time-Of-Flight, direction and coincidence) and sequentially stored, as appeared in RAW data product files, or particle counters given in counts/accumulation units for BIN and TOF modes. Both of them contains data that are splitted and stored into appropriate data files according to the data acquisition mode and the operating sample size (number of PHD bins) of the instrument, in order to maintain fixed width table structure within each data product. The number of rows within the tables is variable and depends roughly on the number of records contained in the associated telemetry packet. An NPD header, specific to each mode of observations and common to NPD1 and NPD2 sensors, is added before a data collection. Instrument Description: = The Neutral Particle Detector (NPD) measures the ENA flux, resolving velocity (in the enregy range 100 eV to 10 keV) and mass (H and O) to help satisfy the following scientific objectives: 1. Determine the instantaneous global distributions of plasma and neutral gas near Venus 2. Energy deposition from the solar wind to the ionosphere NPD consists of two identical pinhole detector cameras, each with a 90 degrees of field-of-view in the intrument azimuth pla...
Instrument ASPERA4
Temporal Coverage 2013-01-01T01:49:29Z/2014-05-14T23:59:59Z
Version V1.0
Mission Description Mission Overview Venus Express is ESA's first mission to Venus. It reuses the design of the Mars Express spacecraft. Many of the instruments are simply upgraded versions of those developed for ESA's Mars Express and Rosetta missions. The scientific objectives of the mission is to study the atmosphere, the plasma environment, and the surface of Venus in great detail. Venus Express was launched by a Soyuz-Fregat launcher from the Baikonour Cosmodrome on 9 November 2005. After separation, Venus Express, of mass 1244 kg,was placed into an interplanetary transfer orbit during approximately 150 days. After a 153 day cruise to Venus the spacecraft entered Venusian orbit on 11 april 2006. The first capture orbit was an eccentric polar and lasted 9 days. Several manoeuvres over the period 15 April-6 May 2006 lowered the spacecraft into its operational orbit: a 24-hour elliptical, quasi-polar orbit. The pericentre altitude is 250 kms and the apocentre altitude is 66000 kms. Pericentre altitude 250 km Apocentre altitude 66000 km Period 24 h Inclination ~90 deg Pericentre latitude 80 deg The mission has been described in many papers [ESA2005; HUNTER2004]. Details about the mission launch sequence and timeline can be obtained from the Mission Calendar [DAUVIN2005] and from the Consolidated Report on Mission Analysis (CREMA) [SANCHEZ&RODRIGU2005]. Mission Phases The mission timeline defines the different spacecraft and payload operations required per phase to prepare the spacecraft for Venus operational orbit acquisition, science data acquisition and transmission. The pre-routine mission phase, which are: - the pre-launch phase - the launch and early orbit phase - the near earth commissioning phase - the interplanetary cruise phase - the venus orbit insertion phase - the venus orbit commissioning phase, the nominal mission phase and the extended mission phases phase are detailed below. PRELAUNCH ---...
Creator Contact EMMANUEL PENOU
Date Published 2011-03-18
Publisher And Registrant European Space Agency
Credit Guidelines European Space Agency, 2011-03-18, VEX-V-SW-ASPERA-2-EXT4-NPD, V1.0. https://doi.org/10.5270/esa-39tzigv