How spacecraft endure the radiation of orbit?


Amongst the challenges that a satellite faces besides a successful launch is how the aerospace electronics endure unpredictable and dangerous radiation of orbit. Radiation influences every space vehicle, be in low orbit or deep space. The highly energized ions inflict havoc on computers making it impossible for them to execute their operations.

Effects of radiation on spacecraft

In space, radiation can influence aerospace electronics in two manners. Firstly, there are transient errors that are short explosions of high energy ions that originate from solar action or from deep space. The ions can disturb electrical charges as they pierce into an integrated circuit.

The amount of transient errors depends on the position of the spaceship in space. The radiation is exceptionally hazardous around Jupiter. The Hubble Space Telescope is turned off completely when moving through high-radiation regions like the Van Allen radiation zone.

Secondly, there are permanent damages due to radiation such as the degradation of circuits. The more exposure of an integrated circuit to high-energy ions, the less efficient it becomes at performing calculations or storing information. A component may fail over time.

Ways to protect spacecraft from radiation

To some extent, it is possible to shield spacecraft electronics from both temporary and permanent damages from the radiations. A research payload aboard the spacecraft can measure levels of radiation and check the efficiency of different shields. Shielding is heavy and cost constraints make it difficult to use it in spacecraft and satellites unless absolutely necessary.

The engineers attempt to balance the consequences of radiation by designing an electronic component. One technique is to design a radiation toughened chip. The chip is actually created in such a manner that it is less vulnerable to the temporary and permanent impacts of radiation. The process comprises designing and manufacturing a unique processor, which in itself is a huge task, given the amount of money and time involved.  

However, not everyone needs radiation hardened spacecraft electronics. A common coping tactic in such a case is TMR (Triple Modular Redundancy). Rather than incorporating special chips, more readily available non-hardened parts can be used. The only condition is that all the three parts have to work in tandem. If any one of them shows an error, the remaining two will correct it.

Strangely, modern day aerospace technology is much stronger but is more susceptible to radiations than the previous computers. Therefore, electronics have to be designed keeping in mind the harsh effects of radiation. Know more on  Civil Space Systems Assembly and Advanced Manufacturing Technologies