Mix master: Modeling magnetic reconnection in partially ionized plasma

Many of the most dramatic events in the solar system — the spectacle of the Northern Lights, the explosiveness of solar flares, and the destructive impact of geomagnetic storms that can disrupt communication and electrical grids on Earth — are driven in part by a common phenomenon: fast magnetic reconnection. In this process the magnetic field lines in plasma — the gas-like state of matter consisting of free electrons and atomic nuclei, or ions — tear, come back together and release large amounts of energy.

Read more

Making connections: Bringing astrophysical processes down to Earth

Magnetic reconnection, a process in which magnetic field lines tear and come back together, releasing large amounts of kinetic energy, occurs throughout the universe. The process gives rise to auroras, solar flares and geomagnetic storms that can disrupt cell phone service and electric grids on Earth. A major challenge in the study of magnetic reconnection, however, is bridging the gap between these large-scale astrophysical scenarios and small-scale experiments that can be done in a lab.

Read more

Hubble observes first confirmed interstellar comet


Hubble has given astronomers their best look yet at an interstellar visitor — comet 2I/Borisov — whose speed and trajectory indicate it has come from beyond our solar system. Comet 2I/Borisov is only the second such interstellar object known to have passed through the solar system.

Read more

How do the strongest magnets in the universe form?

How do some neutron stars become the strongest magnets in the Universe? Astrophysicists have found a possible answer to the question of how these so-called magnetars form. Researchers have used large computer simulations to demonstrate how the merger of two stars creates strong magnetic fields. If such stars explode in supernovae, magnetars could result.

Read more

Pressure runs high at edge of solar system

Out at the boundary of our solar system, pressure runs high. This pressure, the force plasma, magnetic fields and particles like ions, cosmic rays and electrons exert on one another when they flow and collide, was recently measured by scientists in totality for the first time — and it was found to be greater than expected.

Read more