A dataset provided by the European Space Agency

DOI https://doi.org/10.5270/esa-gq31dil
Abstract N/A
Description Data Set Overview = This data set contains level 2 processed data for the SPEDE instrument on SMART-1. The set covers most of February 2004, during which the electric propulsion (EP) was off, in order to secure an undisturbed environment for instrument commissioning activities. SPEDE also performed commissioning activities, consisting of instrument and probe characterisation measurements. These activities and the results have been reported in S1-SPE-RP-3008 'SMART-1 SPEDE Commissioning Report'. The probe on the +X face of the spaceraft has behaved non-nominally since 20 October 2003. An anomaly report has been generated (S1-SPE-RP-3009 'SMART-1 SPEDE Anomaly Report: Probe +X Malfunction'). For SPEDE instrument description see SPEDEPAPER in DOCUMENT directory. The operation of the instrument was controlled by specific Instrument Operations Timeline (ITL) and Direct Operations Request (DOR) sequences, developed for the commissioning activities. During periods between the measurements off SPEDE was either in housekeeping mode (mode 1, which is a mode with 1 sample / minute) or in some of the modes developed for measuring natural plasma. The two specific measurements for the commissioning period were 1) cleaning of SPEDE probes and 2) characterisation of the photoelectron flux of the probes. The measurements are described in the document 'Payload Second Commissioning Scenario Parameter List' (S1-RSSD-LI-004 Issue 5 21 Feb 2004). During the probe cleaning operation, both probes SPEDE were biased to their maximum positive value (-X: 13,9 V, +X: 14,05 V), in order to the probes to repel as much positive ions as possible. Data were collected once per second in Langmuir mode with both probes. The range of angles that could be covered (Y-axis w.r.t. the Sun) was limited by an operational constraint that the angle between the sun direction and the Solar Panels should not exceed 45 degrees. The photoelectron curr...
Instrument SPEDE
Temporal Coverage 2004-02-02T22:46:14Z/2004-02-25T19:31:38Z
Version V1.0
Mission Description Mission Overview SMART-1 is the first of the Small Missions for Advanced Research and Technology (SMART), which are elements of ESA's Horizons 2000 plan for scientific projects. A brief description of the mission and its objectives can be found in the SMART-1 Archive Plan [S1_ARCH_PLAN_2003], and in papers by [MARINI_ET_AL_2002] and [RACCA_ET_AL_2002]. A detailed description of the mission analysis can be found in the Consolidated Report on Mission Analysis [CREMA_2001]. The SMART missions aim at testing key technologies for future cornerstone missions. The primary technological objective of SMART-1 is the flight demonstration of Solar-Electric-Primary-Propulsion (SEPP) for a scientific lunar orbiting spacecraft delivered from launch into a geostationary transfer orbit (GTO). The spacecraft was designed to operate with minimum ground intervention (e.g. one pass every 4 days). However, the use of ground stations throughout the mission was on availability basis with, on average, a pass once a day. SMART-1 was launched from Kourou at 23:14 UTC on 27th Sept 2003 as a co- passenger on an Ariane-5 launcher. The launch mass of the spacecraft was 367kg, including 82.5kg of Xenon propellant for the SEPP and 19kg instrument payload. After release into the geostationary transfer orbit (GTO) the spacecraft acquired initial attitude, autonomously deployed the solar arrays and entered a checkout phase. The GTO had the following parameters. A=24702.3km E=0.71578 Inc=6.999deg RAAN=250.965deg APER=178.246deg Perigee=7020.8km Apogee=42383.7km The first firing of the SEPP occurred at 12:20:21 UT on 30th September 2003. The escape from the Earth was performed by gradually expanding the orbit from the initial geostationary transfer orbit parameters. Continuous thrusting was required for a little over 80 days in order to pass the main radiation belts as quickly as possible, pushing the perigee out to 20,000km. After this ...
Creator Contact Dr. Anssi Malkki
Date Published 2005-10-18
Publisher And Registrant European Space Agency
Credit Guidelines European Space Agency, 2005-10-18, S1-X-SPEDE-4-REFDR-BKGRPLASMA, V1.0. https://doi.org/10.5270/esa-gq31dil