The Sun gave us a magnificent spectacle over the last weekend. A large active region on the solar surface erupted several times over the last week, giving rise to numerous flares and coronal mass ejections, which are large clouds of magnetised solar material that are expelled from the Sun with speeds reaching 7 million km/s. When such clouds hit the Earth’s magnetic field, they cause strong disturbances in the Earth’s magnetic bubble. These disturbances result in acceleration of charged particles that can reach the Earth’s atmosphere, creating a fascinating display of Northern lights, or Aurora Borealis.
The first of the coronal mass ejections hit the Earth on Friday afternoon, and gave rise to the biggest geomagnetic storm in almost 20 years. The resulting Aurora were seen all over the UK and Ireland, and around the world including Europe down to Italy, USA down to Texas and Florida, Mexico, and even in Southern Australia, where the lights are called the Southern Lights.
JHI researchers Prof. Silvia Dalla and Dr Timo Laitinen study aspects of the solar eruptions, in particular the Solar Energetic Particles (SEPs) that are accelerated in processes related to the solar flares and coronal mass ejections. These SEPs can damage satellites and disturb navigation and communication systems here at Earth, and are a hazard to astronauts in space. JHI researchers work on understanding how the SEPs propagate from the Sun to near-Earth space, so that this Space Weather risk could be mitigated.
Images credit: M. J. Ward-Thompson. Photos were taken near Salmesbury, Lancashire.
Images credit: T. Laitinen (Dublin)
Images credit: Joanne Pledger (Wigan)
Images credit: Tom Scragg (South Manchester)
Images credit: Gordon McKay (Kelso)