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Quasars revisited: rapid time variations observed via very-long-baseline interferometry
Science (New York, N.Y.)
|July 16, 1971
Summary
Radio observations of quasars 3C 279 and 3C 273 show rapid structural changes. For 3C 279, this suggests apparent superluminal motion, requiring further study of quasar kinematics.
Area of Science:
- Astronomy and Astrophysics
- Radio Astronomy
- Cosmology
Background:
- Quasars are active galactic nuclei emitting powerful radiation.
- Radio interferometry allows high-resolution imaging of celestial objects.
- Observed rapid structural variations in quasars challenge existing models.
Purpose of the Study:
- To investigate the fine structure and internal kinematics of quasars 3C 279 and 3C 273.
- To analyze rapid variations observed in radio interferometric data.
- To explore potential mechanisms for observed phenomena, including apparent superluminal motion.
Main Methods:
- Utilizing Goldstone-Haystack radio interferometric observations.
- Applying a symmetric double-source model for data interpretation.
- Calculating differential proper motion based on observed data and redshift.
Main Results:
- Rapid variations in the fine structure of quasars 3C 279 and 3C 273 were detected.
- Data for 3C 279 indicate differential proper motion equivalent to an apparent speed approximately ten times the speed of light.
- Several plausible, yet unconfirmed, mechanisms for this apparent superluminal motion were considered.
Conclusions:
- The observed phenomena in quasars like 3C 279 suggest the possibility of apparent superluminal motion.
- Current evidence is insufficient to definitively explain the mechanisms behind these rapid variations.
- Further radio interferometric observations are crucial for understanding quasar structure and internal dynamics.
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