Speaker
Description
In the mid-1970s, a periodic signal with a 160-min interval was detected from
the Sun, which the discoverers interpreted as a gravity mode (g-mode) oscillation,
suggesting it represented vibrations of the Solar surface. Similar signals were
also observed in various extraterrestrial sources, including Active Galactic Nuclei
(AGN). However, later analyses dismissed this signal as merely an artifact caused
by the diurnal effects of Earth’s atmospheric extinction.
The controversy surrounding this signal is significant so much so that: if it is
genuine, it would necessitate a major revision of the Standard Solar Model (SSM),
as it would require treating the Sun as a homogeneous ball of gas, contradicting
one of the major and central tenets of the current SSM.
We propose a model that provides an explanation without requiring drastic
changes to the SSM. Our modification asserts that the convective envelope of the
Sun (and similar stars) is homogeneous, while the core retains all its properties as
outlined in the SSM. Despite previous dedicated searches for the 160-min signal
yielding no results, we believe our model could be crucial in explaining global
g-mode oscillations of stellar surfaces, and thus, pulsations.
In fact, our model suggests that the 160-min signal could shift to a different fre-
quency depending on the current density of the convective envelope. This implies
that if the 160-min signal is not detected, it may have transitioned to a new fre-
quency. Therefore, the focus should be on searching for global g-mode oscillations.
Notably, the SOHO satellite appears to have detected a 24-min signal instead of
the contentious 160-min one.
| Stream | Science or Engineering |
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