An illusion of parallax: explaining a mysterious signal at the edge of the solar system

In 2009, astronomers detected a mysterious source of high-energy, chargeless particles, which appeared to originate from the very edge of the solar system. Through fresh analysis, Dr Li Lu and colleagues at the Chinese Academy of Sciences have discovered that this distance may be an illusion, created by an effect relating to the solar wind as viewed by the commonly used parallax method. If correct, the team’s theory suggests that the as-yet enigmatic signal could actually originate from a source just beyond Earth’s atmosphere.