Astronomers measure the vibrations of a star 21 light years away
Using an instrument on the ground-based Keck telescope in Hawaii, astronomers have been able to measure the internal vibrations of a star 21 light years away, the equivalent of recording a star’s seismology.
Keck Observatory’s KPF instrument precisely measures the motion of the stellar surface towards and away from the observer. Over four consecutive nights, the team used KPF to collect over 2,000 ultra-precise velocity measurements of the star — enabling them to catch the star’s vibrations in action. This is the first asteroseismic inference of the age and radius for a cool star using KPF.
The astronomers next claim that this data allowed them to date the star’s age as 10.2 billion years old, and that it was about 4% smaller in diameter than measured by other observations. Both these conclusions carry uncertainties, but the former has implications if true for the present theories of stellar evolution, since this star appears to be behaving differently than expected for a star this old.
Astronomers have been doing this kind of stellar seismology for the Sun for several decades. To now have instruments sensitive enough to detect it on stars light years away is truly astonishing.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon. from any other book seller, or direct from my ebook publisher, ebookit.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
Using an instrument on the ground-based Keck telescope in Hawaii, astronomers have been able to measure the internal vibrations of a star 21 light years away, the equivalent of recording a star’s seismology.
Keck Observatory’s KPF instrument precisely measures the motion of the stellar surface towards and away from the observer. Over four consecutive nights, the team used KPF to collect over 2,000 ultra-precise velocity measurements of the star — enabling them to catch the star’s vibrations in action. This is the first asteroseismic inference of the age and radius for a cool star using KPF.
The astronomers next claim that this data allowed them to date the star’s age as 10.2 billion years old, and that it was about 4% smaller in diameter than measured by other observations. Both these conclusions carry uncertainties, but the former has implications if true for the present theories of stellar evolution, since this star appears to be behaving differently than expected for a star this old.
Astronomers have been doing this kind of stellar seismology for the Sun for several decades. To now have instruments sensitive enough to detect it on stars light years away is truly astonishing.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon. from any other book seller, or direct from my ebook publisher, ebookit. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
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