Intelsat Q&A

Q&A – Preparing For Space Weather

What are some of the potential dangers of space weather on satellites?

The environment in space can be very harsh, especially during certain peaks in the 11-year sunspot cycle when Corona Mass Ejections (CME) are more frequent. CMEs eject matter and electronic radiation in the form of a plasma consisting primarily of electrons and protons. CMEs disrupt the Earth’s magnetic field; this can result in damage to ground infrastructure that is not adequately protected. Other elements of space weather that might affect satellite operation include deep charging of high energy electrons, surface charging of low energy electrons, micrometeroids and orbital debris.

What steps does Intelsat take to prepare its satellites for the potentially harsh space environment?

We have always designed our satellites to handle the possibility of severe space weather and the impact it might have on satellite equipment. For example, while a geostationary satellite will not be exposed to more than one 11-year solar maximum during its lifetime, our satellites are designed to withstand up to five solar maximum periods. As an industry, we work in close cooperation to share knowledge about the space environment and its weather patterns, incorporating what is learned as part of an ongoing effort to build better spacecraft.

How does the current solar cycle compare to past events?

The current Solar Cycle (Solar Cycle 24) has been one of the least active recorded to date. The monthly number of sunspots peaked at 90 in late 2011, only half of the peak of Solar Cycle 23.

The Naval Research Laboratory issued a press release citing solar storm activity as the likely cause of the Galaxy 15 anomaly? Were they correct? On what did they base that conclusion?

As far as we know, there is no hard evidence that solar storm activity was the cause of the G-15 anomaly. Since the Naval Research Laboratory did not have access to any of our post-anomaly data, we do not know the evidence they used to reach their conclusion.

When investigating an anomaly, we rely on a scientific process using fault tree analysis. Every potential cause is ranked on a probability scale from least probable (eliminated) to most probable. The most probable causes are then validated through a test. This is a very thorough and potentially lengthy process, especially when dealing with complex issues such as the G-15 anomaly.

Preparing satellites for space is an evolving science. If our investigations reveal something we can do differently, we will certainly do it. However, these are state-of-the-art spacecraft built to withstand the space environment, and they have by and large served the industry well through the years. They have a very high rate of mission success.