05-19-2023, 05:24 AM
First Type 1a supernova detected by radio waves
Type 1a supernovae are well observed and act as "standard candles" in astronomy and cosmology as their luminosities are always the same. That means, if you can measure their brightness, you can work out how far away they are so can be used to measure the distance of distant galaxies and are an important part of the cosmic distance ladder; different techniques of measuring distances that rely on consistency and confirmation of the different steps. They have been used extensively to measure the expansion of the universe. They are also a bit different from what you might understand as a typical supernova, as they are caused by a runaway reaction in a white dwarf star due to material being pulled from a companion star which increases the mass beyond a critical limit, and the white dwarf explodes.
SN 2020eyj is a bit different. Firstly, it's the first that has been detected at radio wavelengths. Secondly, thanks to observations made at the Keck Observatory on Mauna Kea, it's the first to show that the supernova ejected massive amounts of helium rather than the usual hydrogen. This means the star it orbited was coming toward the end of its lifetime and had burned through its hydrogen fuel.
"A team of astronomers led by Stockholm University has discovered an unusual Type Ia supernova – or thermonuclear supernova – called SN 2020eyj. Not only did they make the first detection of such a supernova in radio waves, follow-up observations from W. M. Keck Observatory on Maunakea, Hawaiʻi Island also showed strong emission lines of helium.
This marks the first confirmed Type Ia supernova triggered by a white dwarf star that pulled material from a companion star with an outer layer consisting primarily of helium; normally, in the rare cases where the material stripped from the outer layers of the donor star could be detected in spectra, this was mostly hydrogen."
https://www.bigislandvideonews.com/2023/...irst-time/
Also:
https://keckobservatory.org/radio-ia-supernova/
https://www.skyatnightmagazine.com/news/...ia-origin/
Type 1a supernovae are well observed and act as "standard candles" in astronomy and cosmology as their luminosities are always the same. That means, if you can measure their brightness, you can work out how far away they are so can be used to measure the distance of distant galaxies and are an important part of the cosmic distance ladder; different techniques of measuring distances that rely on consistency and confirmation of the different steps. They have been used extensively to measure the expansion of the universe. They are also a bit different from what you might understand as a typical supernova, as they are caused by a runaway reaction in a white dwarf star due to material being pulled from a companion star which increases the mass beyond a critical limit, and the white dwarf explodes.
SN 2020eyj is a bit different. Firstly, it's the first that has been detected at radio wavelengths. Secondly, thanks to observations made at the Keck Observatory on Mauna Kea, it's the first to show that the supernova ejected massive amounts of helium rather than the usual hydrogen. This means the star it orbited was coming toward the end of its lifetime and had burned through its hydrogen fuel.
"A team of astronomers led by Stockholm University has discovered an unusual Type Ia supernova – or thermonuclear supernova – called SN 2020eyj. Not only did they make the first detection of such a supernova in radio waves, follow-up observations from W. M. Keck Observatory on Maunakea, Hawaiʻi Island also showed strong emission lines of helium.
This marks the first confirmed Type Ia supernova triggered by a white dwarf star that pulled material from a companion star with an outer layer consisting primarily of helium; normally, in the rare cases where the material stripped from the outer layers of the donor star could be detected in spectra, this was mostly hydrogen."
https://www.bigislandvideonews.com/2023/...irst-time/
Also:
https://keckobservatory.org/radio-ia-supernova/
https://www.skyatnightmagazine.com/news/...ia-origin/
