SDS-4

SDS-4

Mission type	Technology
Operator	JAXA
COSPAR ID	2012-025C
SATCAT №	38339
Spacecraft properties
Spacecraft type	SDS
Launch mass	50 kilograms (110 lb)
Start of mission
Launch date	17 May 2012, 16:39 (2012-05-17UTC16:39Z) UTC
Rocket	H-IIA 202
Launch site	Tanegashima Yoshinobu 1
Contractor	Mitsubishi
Orbital parameters
Reference system	Geocentric
Regime	Low Earth
Perigee	666 kilometres (414 mi)
Apogee	678 kilometres (421 mi)
Inclination	98.23 degrees
Period	98.05 minutes
Epoch	30 October 2013, 08:31:20 UTC

SDS-4 (Small Demonstration Satellite 4) is a small satellite (50 cm cube with mass of 50 kg) developed by JAXA and to be launched as a secondary payload on the Shizuku mission in mid-2012.

There are four rather specialised systems on the satellite:

• SPAISE (SPace-based Automatic Identification SystEm) - test on-orbit a receiver for picking up signals from Automatic Identification System transmitters on ships well out to sea, and determine how space-based reception is affected by interference between nearby transmitters and by environmental conditions.
• FOX (Flat heat-pipe on-orbit experiment) - to test whether flat heat pipes work in space in accordance with theoretical models and with tests on Earth
• IST (In-flight experiment of Solar absorption rate with THERME) - to acquire information about the effect of sunlight in space on thermal coatings, re-flying the THERME instrument developed by CNES for testing different thermal coatings
• QCM (Quartz Crystal Microbalance) - to test whether a Japanese-manufactured quartz microbalance works well in monitoring contamination of the satellite from assembly to on-orbit operation.