Astridge, short for "Astrophysical Bridge," refers to a hypothetical or observational structure connecting massive cosmic objects, primarily galaxies or galaxy clusters, typically bound by gravity, dark matter, or streams of gas and stars.
Key Characteristics
- Formation: Arises from gravitational interactions during galaxy collisions or close encounters. Tidal forces pull material (stars, gas, dust) out, creating elongated streams.
- Composition: Primarily consists of intergalactic gas, stars stripped from their parent galaxies, and significant amounts of dark matter.
- Observation: Detected via telescopes across various wavelengths (e.g., optical light for stars, radio/X-ray for gas, gravitational lensing for mass/dark matter). Appear as faint, extended filaments.
- Significance: Provides evidence of ongoing galaxy evolution, mergers, and large-scale structure formation in the universe. Tracks the distribution of dark matter.
Important Distinction
While visual bridges might appear to connect galaxies in telescope images, a true astrophysical astridge implies a physical, gravitationally bound structure facilitating the transfer of matter and influencing galactic evolution over cosmic time.
