SaudiSat 4 satellite

SaudiSat 4

Saudi Arabia

Spacecraft nº:

Saudi Arabia spacecraft nº: 25

Prime manufacturer	KACST Space Research Institute
Platform
Operator	KACST Space Research Institute
Mass at launch	100 kg
Dry Mass	kg
Basic shape
Dimension (m)
Equipment	UV LED experiment
Solar array	Solar cells
Stabilization
Propulsion
DC power
Design lifetime

SaudiSat 4 is a Saudi-Arabian technology demonstration satellite developed by the KACST (King Abdulaziz City for Science & Technology).
SaudiSat 4 features a joint NASA Ames and KACST experiment for the control of charge build-up on free-floating test masses critical to the operation of gravitational reference sensors (GRS) on drag-free spacecraft. Essentially, the GRS is an extremely accurate accelerometer that allows its host spacecraft to fly in an orbit defined solely by gravity, and not be affected by solar pressure and atmospheric drag. Its performance is limited in part by the charge build-up on its free-floating test mass.
The UV-LED system removes this charge by shining UV light on the test mass, creating a cloud of electrons through photoemission. The discharge rate is controlled with electrodes. Stanford University demonstrated this technology in the laboratory environment and NASA/ARC implemented the technology in a flight package that was flown on the KACST spacecraft Saudisat 4.
The program has two technical goals: flight qualification of new UV light emitting diodes, and the on-orbit demonstration of AC charge management. The success of UV-LED increases the capability of gravitational reference sensors on future groundbreaking missions such as Laser Interferometer Space Antenna (LISA).

On Jun 19, 2014 launch of a Dnepr rocket from the Yasniy missile base put a record 38 payloads in sun-synchronous orbits ranging from 550 to 610 km at perigee and 620 to 715 km at apogee.
Saudisat-4 is a 100 kg satellite from KACST, Saudi Arabia, with a technology payload including a graviational reference sensor.

Ref.: #7(JR699), #14, #228 - update: 03.12.14