SDS 4

Spacecraft nr:

Japanese spacecraft nr: 175

Launch data: Designation  38339 / 12025C Launch date  17 May 2012 - 16:39 UT Launch site  Tanegashima, YLP-2 Launch vehicle  H-2A-202 Mission  Governmnet: Technology Development LEO Sun-Synchronous Earth orbit: Perigee / Apogee  658 x 674 km Eccentricity  1,14E-03 Inclination  98.18 deg Period  98.06 min

Spacecraft data: Prime manufacturer  Japan Aerospace Exploration Agency (JAXA) Platform   Operator  JAXA Mass at launch  50 kg Dry Mass  48 kg Basic shape  Cube Dimension (m)  sites: 50 sm Equipment   Solar array   Stabilization   Propulsion   DC power  120 W Design lifetime  2 yrs

Description:

• SDS 4 (Small Demonstration Satellite 4) is a small technology experiment satellite developed by JAXA.
• JAXA has been promoting the Small Demonstration Satellite (SDS) program in order to verify new technologies for components and devices in space prior to providing highly established technology to practical satellites and scientific probes.
• An SDS can be developed in a shorter period of time with lower costs compared to a large-size satellite, thus it has an advantage to carry out on-orbit verification and experiments in a timely manner. In addition, we can also foster younger employees by offering them opportunities to experience an overall series of work from a design phase thru satellite operation in space.
• The first SDS (SDS-1), which was about 100 kgs, was launched on January 23, 2009. The SDS-4 project aims to develop a 50-kg class satellite, which is a standard size for a companion payload on the H-IIA Launch Vehicle, and the satellite is scheduled to be launched with the SHIZUKU (Global Change Observation Mission 1st – Water, GCOM-W1) as a piggyback payload.
• Four missions of the SDS project:
  • Space based Automatic Identification System Experiment (SPAISE)
    To demonstrate the function and performance of the future onboard automatic identification system (ASI) receiver system, then to evaluate actual receiving data for possible interference, and to acquire knowledge for the future system structure and receiver function improvement.
  • Flat Heat Pipe (FHP) On-orbit Experiment (FOX)
    To assess the special features of the flat heat pipe (FHP) on orbit, then to compare them with ground test results and theoretical models, and to acquire data for practical use of the FHP.
  • In-flight experiment of space materials using THERME (IST)
    To acquire on-orbit degradation data of the solar absorption rate (?s ) of the thermal insulation material, which is an important feature of the material, by measuring temperature data using the "THERME" material, which was developed by CNES (Centre National d’Etudes Spatiales.)
  • Quartz Crystal Microbalance (QCM)
    To gain on-orbit operation experience of a high-quality onboard quartz crystal microbalance that is domestically manufactured and less expensive while measuring contamination (gas and particles on the surface of the satellite) throughout the satellite operation including its assembly, transportation, launch site work, and on-orbit operations.
• Several technology demonstration experiments and including an experiment to monitor AIS (Automatic Information System) messages transmitted from ships at sea.

Mission details:

• Was planned to launched in Feb 2012, delayed to May.
• SDS-4 was launched by H-IIA flight F21 from Tanegashima on May 17, 2012 into a 1:30am local time sun-synchronous orbit at 670 x 674 km x 98.2 deg. JAXA's 50 kg SDS-4 Small Demonstration Satellite (kogata jissho eisei 4-gata) carries four technology experiments including a space-based AIS (ship tracking) payload.