PROBA-2 Mission

PROBA-2 is the second of ESA’s PRoject for OnBoard Autonomy satellites. It carries four scientific instruments: two particle detectors to monitor the plasma environment of the spacecraft (DSPL and TPMU) and two complementary instruments (SWAP and LYRA) which monitor solar activity.

The Proba satellites are part of ESA’s In-orbit Technology Demonstration Programme, missions dedicated to the demonstration of innovative technologies. In-orbit demonstration is the last step on the technology development ladder. New technology products need to be demonstrated in orbit, particularly when users require evidence of flight heritage or when there is a high risk associated with use of the new technology.

In-orbit demonstration is achieved through experiments on carriers of opportunity, such as the International Space Station, or through dedicated small satellites such as the Proba series, which was created to increase the availability of flight-testing opportunities.

Links

LYRA on ESA website
LYRA data on ESA website
PROBA-2 on ESA website
PROBA-2 Science Center on ROB website

Source and credit: sci.esa.int/proba2/, ESA, PMOD/WRC

PMOD/WRC Instrument: LYRA

PMOD/WRC constructed LYRA (Large Yield Radiometer), a solar radiometer onboard the ESA PROBA-2 mission. The radiometric calibration is traceable to synchrotron source standards. The stability is monitored by on-board calibration sources (LEDs), which allows potential degradation of the detectors and filters to be distinguished. In addition, a redundancy strategy maximizes the accuracy and the stability of the measurements. LYRA benefits from wide bandgap detectors based on diamond: it is the first space assessment of revolutionary UV detectors.

Diamond sensors make the instruments radiation-hard and solar-blind (insensitive to visible light) and therefore eliminate the need for visible light blocking filters. To correlate the data of this new detector technology, well-known technology, such as Si-detectors are also used. The SWAP EUV imaging telescope operates next to LYRA on PROBA-2. Together, they provide a high performance solar monitor for operational space weather nowcasting and research.

The instrument incorporates three filter radiometers, each consisiting of four different optical channels.

  • 121.6 nm (Lyman alpha, interference filter)
  • 200 – 220 nm (Herzberg, interference filter)
  • 17 – 70 nm (Aluminium filter)
  • 1 – 20 nm (Zirconium filter)

LYRA was developed by a Belgian–Swiss consortium, and is now operated by the PI Institute, The Royal Observatory of Belgium (ROB). PMOD/WRC was in charge of design & development tasks, the manufacturing and environmental testing of the instrument.

Source and credit: sci.esa.int/proba2/, ESA, PMOD/WRC

Still in operation

Two weeks after the PROBA-2 launch, on 16 November 2009, LYRA was switched on for the first time. During the following weeks, all functions were tested, such as bake-out, decontamination procedure, dark current, calibration procedure, determination of the nominal integration time, and characterisation of the LED stability signal.

Since then, LYRA has continuously provided valuable data and is still in operation, although the nominal mission duration expired many years ago. LYRA can be considered as a very successful project and contributes important data for space weather research. Various papers have been published meanwhile by the involved institutions.

Mission Facts

Launch date 2 November 2009 (Plesetsk, Russia)
Rocket Rockot
Orbit Altitude between 700 km and 800 km; Sun-synchronous; Inclination 98.298°
Nominal mission duration Still in operation
Mass of the satellite 130 kg
Dimensions of the satellite 0.6 × 0.6 × 0.8 m
Mass of LYRA 4.5 kg
Dimensions of LYRA 222 x 76 x 395 mm
Power consumption satellite 70 – 110 W
Power consumption LYRA 2.7 W (Nominal mode)
Telemetry satellite S-band channel provides a 64 Kbit/sec packet telecommand uplink and a
two-million symbols/sec packet telemetry downlink
Telemetry LYRA Nominal: 0.03 kByte/s
Funding Swiss Space Office SSO / ESA PRODEX Programme
Further interesting facts PI Institute: Royal Observatory of Belgium

Source and credit: sci.esa.int/proba2/, ESA, PMOD/WRC