14-Jan-2023: Researchers from the Center for Astrophysics (CfA), Harvard & Smithsonian have generated a 3D magnetic map of the cavity called Local Bubble.
What are Local Bubbles?
- 1,000-light-year-wide cavity or superbubble in the Milky Way
- Low-density region in the interstellar medium (ISM)
- Created by a series of supernovae explosions 30-50 million years ago
- Interstellar medium is the material between stars
Supernovae
- Powerful and luminous explosion at end of life of a massive star
- Collapse of the core of the star triggers massive release of energy
- Enriches ISM with heavy elements and propagates cosmic rays
Two main types:
Type I: caused by thermonuclear explosion of a white dwarf star in a binary system
Type II: caused by gravitational collapse of the core of a massive star
Observations of Local Bubbles
- By using Gaia and Planck space-based observatories from European Space Agency (ESA)
- Gaia identified location and local concentration of cosmic dust to trace boundaries of Local Bubble
- Planck provided information on magnetic alignment of cosmic dust, allowing generation of 3D magnetic field orientation on the surface of Local Bubble