Key Highlights
- Astrophysicists estimate that the short bursts of brightness that flash like a lighthouse occur because of dense regions of interstellar plasma scattering the radio waves emitted by the pulsar.
- More detailed observations are explained below in this article.
Pulsars are the rapidly spinning remnants of stars that flash like a lighthouse. Occasionally pulsars show extreme variations in brightness. Astrophysicists predict that these short bursts of brightness occur due to dense regions of interstellar plasma (the hot gas between stars) scattering the radio waves emitted by the pulsar.
However, they still don’t know where the energy sources required to form and sustain these dense plasma regions come from. More detailed observations of their small-scale structure are required to better understand these interstellar formations. A promising avenue for this is the scintillation, or “twinkling,” of pulsars.
When the interstellar plasma scatters the radio waves of a pulsar, the separate waves interfere and create an interference pattern on the Earth. As the Earth, pulsar, and plasma move relative to each other, this pattern is observed as brightness variations in time and frequency: the dynamic spectrum. It is scintillation, or “twinkling.”
The scattering and twinkling occur in small regions of the plasma thanks to the point-like nature of pulsar signals. Following specialized signal processing of the dynamic spectrum, vivid parabolic features known as scintillation arcs related to the image of the pulsar’s scattered radiation in the sky can be observed.
Astrophysicists can estimate the mass of J1603-7202’s orbital companion using the orbit measurement. It was calculated to be about half the mass of the Sun. When considered with the highly circular orbit of J160-7202, this implies the companion is similar to a stellar remnant composed of carbon and oxygen, a rarer find around a pulsar than the more common helium-based remnants.
As astrophysicists now possess a near-complete orbit model, it’s currently possible to transform scintillation observations of J1603-7202 into on-sky scattered images and map the interstellar plasma at Solar System scales. Creating images of the physical structures that cause extreme scattering of radio waves may give us a better understanding of how such dense regions form and the interstellar plasma’s role in galaxy evolution.
For more updates on Space tech and news Click here
