AAUSat-2

AAUSat-2
AAUSAT-II, alongside its engineering model, ahead of launch
NamesAAUSat-II
Aalborg University CubeSat-2
Mission typeTechnology demonstration
OperatorAAU Student Space
COSPAR ID2008-021F Edit this at Wikidata
SATCAT no.32788
Websitewww.aausatii.aau.dk
Mission duration6 months (planned)
4 years (primary) 15 years (ongoing)
Spacecraft properties
SpacecraftAalborg University CubeSat-2
Spacecraft type1U CubeSat
BusCubeSat
ManufacturerAAU Student Space
Launch mass1 kg (2.2 lb)
Dimensions10 × 10 × 11.3 cm (3.9 × 3.9 × 4.4 in)
Start of mission
Launch date28 April 2008, 03:53:51 UTC[1]
RocketPolar Satellite Launch Vehicle (PSLV-CA)
Launch siteSatish Dhawan Space Centre, Second Launch Pad
ContractorIndian Space Research Organisation
Entered serviceMay 2008
End of mission
DisposalPrimary mission end
DeactivatedMarch 2012
Orbital parameters
Reference systemGeocentric orbit[2]
RegimeSun-synchronous orbit
Perigee altitude615 km (382 mi)
Apogee altitude634 km (394 mi)
Inclination97.9°
Period97.4 minutes
Instruments
Attitude Determination and Control System (ADCS)
Gamma ray detector

AAUSAT-II (Aalborg University CubeSat no 2), is the second student-built CubeSat built and operated by students from Aalborg University in Denmark.[2] It was launched 28 April 2008 05:53:51 UTC from Satish Dhawan Space Centre in India on a Polar Satellite Launch Vehicle (PSLV) launch vehicle. AAUSAT-II carries a gamma radiation sensor.

Educational objective

The primary purpose of construction of satellites at the University of Aalborg is to give the students engineering capabilities beyond what is normally achieved within a masters program.

History

Student satellite activities at Aalborg University (AAU) started in 2003 as a result of AAU's involvement in the first pure Danish research satellite, Ørsted, which was successfully launched in 1999. AAUSAT-II's predecessor was AAU CubeSat which was constructed in the period 2001-2003 and was launched 30 June 2003. The project started in the summer 2003. The construction of AAUSAT-II began in 2005.

Operations

After the launch on 28 April 2008, AAUSat-2 beacon was received at Cal Poly University in California but two-way amateur radio communications could not be achieved as it turned out that AAUSat-2 was transmitting at a lower level than anticipated. After upgrades to the ground station were completed, fully functional two-way communication were achieved and continued with normal operations until May 2009 after a year of successful operation.

The ground station has remained in operation and beacons are received on a regular basis and AAUSat-2 is still considered operational - although heavy tumbling is observed (December 2009). Beacons are still received on regular basis in March 2011. In addition, AAUSat-2 does receive and acknowledge commands from ground and log files has been requested and received. Due to the very high tumbling (more than 2.5 Hz) it has not been possible to decode log files.

Below is a snapshot of the radio communication. On left side is a beacon, next a request for log is issued and AAUSat-2 reply with a transmission of the logfile. Notice the high tumbling rate.

In March 2012, the AAUSAT-II mission was officially retired by the project — but the CubeSat is still up and running. As of 2022, the satellite continues to function.[2]

Mission definition

AAUSAT-II consists of several sub-systems:

  • ADCS: Attitude Determination and Control System
  • CDH: Command and Datahandling System
  • COM: Communication System
  • EPS: Electrical Power System
  • GND: Ground Station
  • MCC: Mission Control Center
  • MECH: Mechanical System
  • OBC: On-board Computer System
  • P/L: Payload System

Technical Facts:

Dimensions 100 by 100 by 113 millimetres (3.9 in × 3.9 in × 4.4 in) CubeSat standard
Mass 750 grams (26 oz)
Expected lifetime Minimum 1 month, extended until end of lifetime
Attitude determination system Sun sensors, gyro sensors, magnetometers
Attitude control system Momentum wheel and magnetic coils
Power Solar-cell panels located in satellite surface
Batteries Li-ion 8.2V 2200 mAh
Power bus 3.3 and 5V regulated

Amateur radio information

  • Callsign: OZ2CUB
  • Up/downlink: 437.425 MHz AFSK & FSK
  • Bit rate: 1200-9600 bit/s (1200 as standard mode)
  • AX.25 FM CW TLM

See also

References

  1. ^ McDowell, Jonathan. "Launch Log". Jonathan's Space Report. Retrieved 22 January 2014.
  2. ^ a b c "AAUSAT-II (Aalborg University CubeSat-2)". ESA eoPortal Directory. 2021. Retrieved 26 October 2021.