Fiery Fate: Hyperactive Sun sends Australian satellites crashing back to Earth

Australian Satellites Burn Up Early Due to Intense Solar Weather

Three small Australian satellites from Curtin University’s Binar Space Program recently burned up in Earth’s atmosphere, marking a premature end to their mission. These CubeSats—Binar-2, Binar-3, and Binar-4—were expected to last around six months in low Earth orbit but managed only two months due to unexpected solar activity.

Typically, satellites in low Earth orbit (up to 2,000 km) experience gradual orbital decay, eventually re-entering and burning up. However, recent high solar activity has accelerated this process for satellites lacking altitude control systems, such as university research satellites. The Sun's increased activity—marked by more sunspots, solar flares, and strong solar wind—has intensified space weather, affecting satellites, astronauts, and communications.

The Sun's 11-year solar cycle has reached a peak (solar cycle 25), with current activity levels significantly surpassing predictions. This solar surge has caused the Earth’s upper atmosphere to expand, creating greater drag on satellites like the Binar CubeSats. Unlike larger satellites equipped with thrusters, these CubeSats had no means to counteract the increased atmospheric drag, leading to their rapid descent and early destruction.

The heightened solar activity has also led to more visible auroras closer to the equator, stronger solar radiation impacting satellite electronics, and increased atmospheric drag for low Earth orbit objects like the International Space Station and Starlink satellites. While commercial satellites can adjust their orbits, these adjustments come at a high operational cost.

The Binar Space Program, aiming to advance space research, has nonetheless provided valuable insights into solar activity’s impact on space operations. The Sun’s activity is expected to decline by 2026 and reach a minimum by 2030, which should offer more stable conditions for future missions.

Despite the early loss of Binar-2, 3, and 4, the program is moving forward with new satellite projects, anticipating a more favorable space environment.