The Atmospheric Coupling and Dynamics Explorer (ARCADE) Mission is a science microsatellite being developed at the Satellite Research Centre at NTU School of Electrical and Electronic Engineering. ARCADE is also the fourth satellite (INSPIRESat-4) in the INSPIRE (International Satellite Program in Research and Education) satellite series. INSPIRE is an international consortium promoting space science and engineering with NTU Singapore being one of the primary leaders of the program. The ARCADE mission has contributions from Institutions in Germany, Taiwan, India and US. One of the unique features of the mission is to fly an electric propulsion system to progressively lower the altitude from an initial 530 km to 350 km to fly and image the Earth from Very Low Earth Orbit (VLEO). ARCADE will be a pathfinder for Singapore’s more ambitious plans to explore the VLEO region.
ARCADE is a 27U spacecraft (30x30x30 cm) carrying an ionospheric plasma payload which will make ion temperature, velocity, density and electron temperature measurements. The ARCADE mission provides an excellent opportunity to study the equatorial ionosphere at low altitudes where the ion and electron density are much higher. The ionosphere is a region around the Earth between 100-700 km composed mainly of charged particles and electrons. In-Situ measurements of ions in the region below 400 km is sparse and can give scientists insight into the composition and dynamics of ion generation and evolution in this region of the Earth’s atmosphere. This has implications for understanding the effect of the ionosphere on GPS signal scintillation, propagation of electromagnetic waves and communication irregularities caused by the ionosphere. The ion plasma payload, called the Compact Ionosphere Probe (CIP) has been built by the National Central University in Taiwan.
Another addition to the mission is a Spatial Heterodyne Interferometer (SHI) Infra-Red Imager for imaging the Mesosphere and Lower Thermosphere (MLT) region between 60-120 km. The SHI instrument will provide temperature information and help for understanding the dynamics of the equatorial MLT region. The SHI instrument has been developed by Forschungszentrum Jülich affiliated with University of Wuppertal in Germany. Together with CIP, Atmolite measurements are expected to reveal the effects of lower atmosphere coupling on the ionosphere and structures observed in the equatorial ionosphere. The spacecraft will fly a third NTU payload to study atomic oxygen effect on degradation of materials and perovskite solar cells in VLEO. ARCADE will also fly an electric propulsion hall effect thruster developed by French company 'Thrust Me’ to bring the spacecraft to VLEO from its initial orbit and do Earth imaging. A team of 15 NTU students have worked on this project over the past 5 years including undergraduate and graduate students from EEE.
List of Organizations involved.
- National Central University, Taiwan
- Forschungszentrum Jülich, Germany
- LASP, University of Colorado, USA
- Indian institute of Space Science and Technology, India
|Orbit||Near equatorial 550-km to 350 km|
|Design lifetime||1 year for LEO|
|Dimensions (L x W x H)||Launch: 32.1 x 31.9 x 32.3 cm3|
Orbit: 70 x 94 x 46 cm3
|ADCS||12 coarse sun-sensors, IMUs, 1 star tracker|
3 magnetorquers, 3 reaction wheels
3 deployable solar panels (25W peak power.), One body mount solar panel, (25W peak power).
Total 100W BOL Peak Power
24 Ah @ 8.4 V nominal, 2s2p Li-Ion cells. (x2)
Total 192 Wh
|TT&C & Payload Downlink||9600bps UHF GFSK uplink, 50Mbps X band downlink|
|Payload||Spatial Heterodyne Interferometer|
Compact Ionosphere Probe
Atomic Oxygen Payload
|Launch adapter||IBL-230 for PSLV|