May 3, 2024

In a First, Owens Valley Observatory Harnesses Radio Waves To Illuminate Solar Eclipse’s “Ring of Fire”

Upper row: Radio pictures of the 2023 Oct. 14 solar eclipse observed by the Long Wavelength Array at the Owens Valley Radio Observatory Bottom row: Schematic representation of what visible images of the eclipse looked like at the same time. Credit: Sijie Yu
The Owens Valley Radio Observatory used their upgraded Long Wavelength Array to capture an unique “radio eclipse” image throughout the October 14 solar event, revealing comprehensive insights into the suns corona and associated phenomena.
A New Perspective on the Solar Eclipse
On October 14, as many Californians were treated to a partial solar eclipse (see bottom right “noticeable” image showing the suns crescent glancing out from behind the moon), scientists at the Owens Valley Radio Observatory (OVRO) took in a various view. Utilizing OVROs Long Wavelength Array (OVRO-LWA), they measured radio wavelengths in between 20 and 88 megahertz (MHz) to create a picture of the “radio eclipse.”
In the images and video below, the dotted lines show the moons location and the strong lines reveal the visible suns limb. Distortions in the video are caused by the suns ionosphere. The radio waves extending beyond the suns edge are produced from its corona, developing a “ring of fire” effect observable even outside the course of the complete annular eclipse.

Observation of the October 14 solar eclipse approaching the optimum occultation, recorded by Owens Valley Radio Observatory– Long Wavelength Array (OVRO-LWA). Significantly, the radio sun sometimes distorts due to the refraction of radio waves by the fluctuating ionosphere, an impact reminiscent of seeing the sun under a rippling water surface.
Technical Insights and Significance
” Science-wise, this is a distinct chance to study the suns prolonged corona with the highest resolution possible at these wavelengths, benefiting from the moons limb as a moving knife edge to increase the efficient angular resolution,” says Bin Chen, a solar astrophysicist and associate teacher at the New Jersey Institute of Technology, who co-leads OVRO-LWAs research study on the sun.
Observation of the October 14 solar eclipse approaching the maximum occultation, taped by Owens Valley Radio Observatory. Credit: Sijie Yu/NJIT
Improvements at OVRO-LWA
The telescope can now survey the sky much faster than any other radio telescope operating at frequencies under 100 MHz. The range spots radio waves throughout the whole sky near-continuously, keeping an eye on for coronal mass ejections from close-by stars, browsing for the magnetic fields of exoplanets, and providing insights on the early universe in addition to performing multifaceted research studies of our sun.

The radio waves extending beyond the suns edge are emitted from its corona, developing a “ring of fire” result observable even outside the path of the complete annular eclipse.

Observation of the October 14 solar eclipse approaching the maximum occultation, taped by Owens Valley Radio Observatory– Long Wavelength Array (OVRO-LWA). Significantly, the radio sun sometimes misshapes due to the refraction of radio waves by the fluctuating ionosphere, an impact reminiscent of seeing the sun under a rippling water surface. The array spots radio waves throughout the entire sky near-continuously, monitoring for coronal mass ejections from close-by stars, searching for the magnetic fields of exoplanets, and providing insights on the early universe in addition to performing complex studies of our sun.