Astronomers identify first progenitor star for Type 1C supernovae
Astronomers have for the first time identified a progenitor star for a Type 1C supernovae.
[The search for supernovae progenitor stars has found] a few pre-supernova stars. But the doomed stars for one class of supernova have eluded discovery: the hefty stars that explode as Type Ic supernovas. These stars, weighing more than 30 times our Sun’s mass, lose their hydrogen and helium layers before their cataclysmic death. Researchers thought they should be easy to find because they are big and bright. However, they have come up empty. Finally, in 2017, astronomers got lucky. A nearby star ended its life as a Type Ic supernova. Two teams of researchers pored through the archive of Hubble images to uncover the putative precursor star in pre-explosion photos taken in 2007. The supernova, catalogued as SN 2017ein, appeared near the center of the nearby spiral galaxy NGC 3938, located roughly 65 million light-years away.
An analysis of the candidate star’s colors shows that it is blue and extremely hot. Based on that assessment, both teams suggest two possibilities for the source’s identity. The progenitor could be a single star between 45 and 55 times more massive than our Sun. Another idea is that it could have been a binary-star system in which one of the stars weighs between 60 and 80 times our Sun’s mass and the other roughly 48 solar masses. In this latter scenario, the stars are orbiting closely and interact with each other. The more massive star is stripped of its hydrogen and helium layers by the close companion, and eventually explodes as a supernova.
As can be seen by the quote above, identifying the star that exploded still leaves much unknown, including whether the star is a single or a binary. Still, they finally have some idea what kind of star erupts in a Type IIC supernovae, which will help constrain the theories for explaining the cause of these explosions.
Note also that this identification will not be confirmed until the supernova itself completely fades in about two years. They might find when that happens that the candidate progenitor is still there, meaning it was not the progenitor of the supernova at all.
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 or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. 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
Astronomers have for the first time identified a progenitor star for a Type 1C supernovae.
[The search for supernovae progenitor stars has found] a few pre-supernova stars. But the doomed stars for one class of supernova have eluded discovery: the hefty stars that explode as Type Ic supernovas. These stars, weighing more than 30 times our Sun’s mass, lose their hydrogen and helium layers before their cataclysmic death. Researchers thought they should be easy to find because they are big and bright. However, they have come up empty. Finally, in 2017, astronomers got lucky. A nearby star ended its life as a Type Ic supernova. Two teams of researchers pored through the archive of Hubble images to uncover the putative precursor star in pre-explosion photos taken in 2007. The supernova, catalogued as SN 2017ein, appeared near the center of the nearby spiral galaxy NGC 3938, located roughly 65 million light-years away.
An analysis of the candidate star’s colors shows that it is blue and extremely hot. Based on that assessment, both teams suggest two possibilities for the source’s identity. The progenitor could be a single star between 45 and 55 times more massive than our Sun. Another idea is that it could have been a binary-star system in which one of the stars weighs between 60 and 80 times our Sun’s mass and the other roughly 48 solar masses. In this latter scenario, the stars are orbiting closely and interact with each other. The more massive star is stripped of its hydrogen and helium layers by the close companion, and eventually explodes as a supernova.
As can be seen by the quote above, identifying the star that exploded still leaves much unknown, including whether the star is a single or a binary. Still, they finally have some idea what kind of star erupts in a Type IIC supernovae, which will help constrain the theories for explaining the cause of these explosions.
Note also that this identification will not be confirmed until the supernova itself completely fades in about two years. They might find when that happens that the candidate progenitor is still there, meaning it was not the progenitor of the supernova at all.
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 or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. 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
I know space is big and nearby is relative, but referring to a star in another galaxy 65 million light-years away as a “nearby star” made me smile.
Marcus Sammer: Yup, from the point of view of astronomers, a galaxy only 65 million light years away is “nearby.” Sounds strange, but when compared to the distances of most galaxies, in the billions of light years, this is practically next door.
Part Fun, Part Science:
“An Astronomer’s Guide to The Star Trek Universe :
Mapping the United Federation of Planets”
-Space Telescope Science Institute
https://youtu.be/DrDhh4m4GkE?t=1074
Bob did you saw this?
Gravitational waves spotted last year were created by merger of hyper-massive neutron star, scientists say
Researchers analyzed data from the LIGO and Virgo gravitational wave detector
The team initially thought the event led to the formation of a huge black hole
But, they instead found the two neutron stars merged to become one huge one.
https://www.dailymail.co.uk/sciencetech/article-6394451/Scientists-spot-gravitational-waves-caused-hyper-massive-neutron-star.html?ito=social-twitter_mailonline
Will Smith: This was posted by me yesterday: Neutron star merger caused gravitational wave?
You are not doing your homework and reading Behind the Black closely. :)
Is this serious? We are looking so far into the past, how ca we use this information? Near the center of the spiral galaxy NGC 3938, 65 million light-years away is NEARBY?!
ONE Light Year is 5,878,625,373,183.6 miles. That is about 5.88 trillion miles! What they saw happened 65 MILLION YEARS AGO and is so far away 65 million TIMES 5.88 trillion miles, nothing we observe at these mind bending distances means anything!
–Alan
@ Alan….
We don’t have much choice…. If we want to study the universe, we must accept we do so through the lens of time.
Unless we have the rules of nature completely wrong, said rules were the same 65 million years ago as they are now .. so to say observations of distant astronomical objects and events mean nothing is nonsensical.
Alan,
The lens of time, as Lee S put it, is also a benefit. The farther distance that we can see, the farther back in time that we can see. It means that we can look at galaxies soon after they formed after the big bang almost 14 billion years ago, and that is interesting, meaningful information. So, yes, 65 million years ago is not that long on the universe’s timeline, but it gives us additional meaningful data.
It may not affect the price of rice in Nice, but it helps to sate our curiosity about the universe, where we came from, and where we are going.