Increased solar activity results in shorter lifespan of Binar CubeSats

Last week, three small Australian satellites from Curtin University’s Binar Space Program re-entered Earth’s atmosphere and burned up much earlier than expected, halting valuable research opportunities. These CubeSats, named Binar-2, Binar-3 and Binar-4, were launched with an initial lifespan of six months and lasted only two months in low Earth orbit (LEO), a situation attributed to the increased solar activity that has posed problems for satellites. operations in recent years.

Solar activity is rising, defying predictions

According to Live Science reportSolar activity has recently exceeded predictions, with levels one and a half times higher than expected for the current solar cycle, known as Solar Cycle 25. This wave, characterized by an increase in solar flares, sunspots and solar wind, is caused by fluctuations in the magnetic field of the sun, which changes polarity approximately every eleven years. Although solar cycles have been mapped, solar weather forecasting is still in its infancy, making accurate predictions challenging.

The space weather effects on Earth have been significant. Intense auroras have been observed closer to the equator, and increased solar wind has increased ionizing radiation, posing additional dangers to astronauts and high-altitude flights. Satellites in LEO, especially those without thrusters or altitude adjustment systems such as the Binar CubeSats, face constant drag that accelerates their orbital decay during periods of increased solar activity.

The impact on satellite missions

The early demise of the Binar CubeSats highlights the need for improved space weather forecasting to support satellite operations. CubeSats, like those in Curtin’s program, are used extensively for university research and often lack the ability to counteract the increased atmospheric drag caused by space weather. Their sudden return illustrates the risks satellites face during solar peaks.

Further Binar missions are already in development, with launches planned for late 2026, when solar activity is expected to decline. As minimum solar conditions approach in 2030, the next generation of CubeSats can operate in a more stable space environment, allowing for longer-lasting research efforts.