Hidden structures in space
Large portions of the cosmos are difficult to observe directly, even with the most sophisticated telescopes available today. Material such as gas and dust does not produce its own light and becomes apparent only where it obscures radiation from stars and galaxies. Magnetic fields pose an even greater challenge, since standard electromagnetic waves usually pass through them without noticeable effect.
A new instrument and its potential
A study posted on the arXiv preprint server by Manisha Caleb of the University of Sydney together with co-authors suggests a possible solution. According to the work, a telescope system now being commissioned could employ a especially energetic astronomical event to gain fresh insight into regions of the universe that are otherwise hard to examine.
- Gas and dust stay invisible unless they block background light.
- Magnetic fields are poorly traced by ordinary light.
- Fast radio bursts can act as probes of concealed cosmic matter.
The Square Kilometre Array (SKA) is currently under construction and is expected to serve as the observational platform for detecting and analysing these signals. The researchers contend that the brief, intense radio flashes known as fast radio bursts are well suited to decode the properties of matter and fields along their propagation path.
If the method proves effective, the layout of intergalactic gas and the intensity of cosmic magnetic fields could be mapped with greater accuracy than before. This would address a core difficulty in astrophysics: making visible what emits no light of its own.