A groundbreaking discovery was made last year when a fast radio burst was traced back to an unexpected source. While most of these mysterious radio signals are believed to originate from deep space and are not associated with technology, the burst detected on 13 June 2024 was found to have come from a NASA satellite that has been inactive in Earth’s orbit for over 50 years.
A team led by astronomer Clancy James from Curtin University in Australia reported the detection of the burst using the Australian Square Kilometer Array Pathfinder (ASKAP). Through careful analysis, they were able to link the burst to the long-decommissioned Relay 2 satellite.
This finding sheds light on the importance of recognizing and understanding anthropogenic signals as our technological capabilities in astronomy continue to advance. Signals from Earth-based technology, such as a truck or a microwave oven, have been known to cause confusion in scientific observations. In this case, the defunct NASA satellite, Relay 2, which has been orbiting Earth since 1964, was responsible for the burst of radio emission.
Fast radio bursts are a fascinating cosmic phenomenon that astronomers are still trying to unravel. These brief but powerful bursts of radio waves can be equivalent to the energy emitted by 500 million Suns in just a millisecond. While most fast radio bursts originate from distant galaxies, the source of this particular burst was surprisingly close to Earth, only 4,500 kilometers away.
The researchers identified two possible explanations for the burst: an electrostatic discharge or a plasma discharge resulting from a micrometeoroid impact. While micrometeoroids are a known hazard in space, the team leans towards an electrostatic discharge as the likely cause.
This discovery not only provides valuable insights for future observations of similar events but also highlights the risks posed by electrostatic discharges in Earth’s orbit. The researchers suggest that this observation could lead to new methods for remote sensing of arc discharges from satellites and improve our understanding of space hazards.
The study, which has been accepted for publication in The Astrophysical Journal Letters, offers a new perspective on the detection and interpretation of radio signals in space. It underscores the need for continued research and monitoring of Earth’s space environment to mitigate potential risks to spacecraft and enhance our understanding of astrophysical phenomena.
For more information on this groundbreaking discovery, you can access the full research paper on arXiv.