It is understood that Firefly-1 will be launched by a Russian launch vehicle and sent into the elliptical orbit of Mars; After that, the satellite will independently complete the exploration task of the space environment of Mars. During this period, the Russian "Forbes" Mars probe will land on the surface of Phobos, extract Phobos soil samples and return to Earth. Firefly-1 will also work with Forbes to complete the occultation exploration of the Martian environment. "Firefly-1" includes four key technologies: ultra-long-distance measurement and control communication; Autonomous control; Ultra-low temperature adaptation technology, 8.8 hours long fire shadow; There are also difficulties such as thermal control technology and lightweight technology, which are referred to as "three controls and one integration". Generally speaking, the distance between artificial earth satellites and the earth ranges from several hundred kilometers to tens of thousands of kilometers, the distance between artificial earth satellites and the moon earth is about 384,000 kilometers, and the distance between artificial earth satellites and Mars is about 350 million kilometers. TT&C data transmission of satellite needs to overcome the difficulties of signal attenuation and transmission delay to realize effective communication in deep space environment. The signal sent to Mars is thousands of times weaker than the signal received by the Earth satellite.
Because Mars is far away from the Earth, it takes a long time for the Mars probe to receive the ground remote control instruction. When orbiting Mars, the active control ability of the ground monitoring station for remote control is much lower than that of the earth satellite. Therefore, the requirements for the on-board autonomy of the Mars probe are greatly improved, so as to reduce the satellite's dependence on the ground system, and it cannot be real-time remote control like the Earth satellite.
In addition, "firefly-1" will encounter seven "long fire shadows" during the whole detection process, and the time is as long as 8.8 hours. At this time, when Mars will run between the probe and the sun, Firefly-1, which mainly relies on solar energy, has to go to sleep in order to save energy. Then, it will wake up after the "long fire shadow" ends. After 8.8 hours of dormancy, the ambient temperature of Firefly-1 reached below-200℃. When the machine is dormant, too low temperature will affect the operation of the machine. If the machine is "frozen to death", it is impossible to "live" after being electrified. Firefly No.1-Design parameter size: 750×750×600 mm Weight: 1 10 kg
Power: 90 watts (average) 180 watts (peak)
Data transmission rate: 80 bits/second
2×3 solar panels with a total length of 7.85 meters.
Task Type: Tracking
Orbiting star: Mars
Launch date: June 6, 2009 to 20091October 6.
Launch vehicle: Soyuz launch vehicle
Task duration: 1 year.
Mass: 1 10 kg
Track inclination: 5
Orbital operation period: 3 days