Astronomers may receive got finally uncovered the long-sought progenitor to a specific type of exploding star past times sifting through NASA Hubble Space Telescope archival data. The supernova, called a Type Ic, is sentiment to detonate later on its massive star has shed or been stripped of its outer layers of hydrogen together with helium.
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| Artist's concept of a blueish supergiant star that i time existed within a cluster of immature stars inward the spiral galaxy NGC 3938, located 65 1000000 light-years away. It exploded equally a supernova inward 2017, together with Hubble Space Telescope archival photos were used to locate the doomed progenitor star, equally it looked inward 2007. The star may receive got been equally massive equally l suns and burned at a furious rate, making it hotter together with bluer than our sun. It was so hot, it had lost its outer layers of hydrogen and helium. When it exploded inward 2017, astronomers categorized it equally a Type Ic supernova because of the lack of hydrogen and helium inward the supernova's spectrum. In an option scenario (not shown here) a binary companion to the massive star may receive got stripped off its hydrogen together with helium layers [Credit: NASA/ESA/J. OLMSTED (STScI)] |
Finally, inward 2017, astronomers got lucky. Influenza A virus subtype H5N1 nearby star ended its life equally a Type Ic supernova. Two teams of astronomers pored through the archive of Hubble images to uncover the putative precursor star inward pre-explosion photos taken inward 2007. The supernova, catalogued equally SN 2017ein, appeared close the centre of the nearby spiral galaxy NGC 3938, located roughly 65 1000000 light-years away.
This potential uncovering could yield insight into stellar evolution, including how the masses of stars are distributed when they are born inward batches.
"Finding a bona fide progenitor of a supernova Ic is a big prize of progenitor searching," said Schuyler Van Dyk of the California Institute of Technology (Caltech) inward Pasadena, Pb researcher of i of the teams. "We directly receive got for the showtime fourth dimension a clearly detected candidate object." His team's newspaper was published inward The Astrophysical Journal.
Influenza A virus subtype H5N1 newspaper past times a instant team, which appeared inward the Monthly Notices of the Royal Astronomical Society, is consistent with the before team's conclusions.
"We were fortunate that the supernova was nearby together with really bright, almost v to 10 times brighter than other Type Ic supernovas, which may receive got made the progenitor easier to find," said Charles Kilpatrick of the University of California, Santa Cruz, leader of the instant team. "Astronomers receive got observed many Type Ic supernovas, but they are all equally good far away for Hubble to resolve. You require i of these massive, brilliant stars inward a nearby galaxy to larn off. It looks similar most Type Ic supernovas are less massive together with thence less bright, together with that's the argue nosotros haven't been able to regain them."
An analysis of the object's colors shows that it is blueish together with extremely hot. Based on that assessment, both teams suggest 2 possibilities for the source's identity. The progenitor could live a unmarried hefty star betwixt 45 together with 55 times to a greater extent than massive than our Sun. Another sentiment is that it could receive got been a massive binary-star organisation inward which i of the stars weighs betwixt lx together with fourscore solar masses together with the other roughly 48 suns. In this latter scenario, the stars are orbiting closely together with interact with each other. The to a greater extent than massive star is stripped of its hydrogen together with helium layers past times the unopen companion, together with eventually explodes equally a supernova.
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| This NASA Hubble Space Telescope icon of the nearby spiral galaxy NGC 3938 shows the place of supernova 2017ein, in a spiral arm close the brilliant core. The exploded star is a type Ic supernova, sentiment to detonate later on its massive star has shed or been stripped of its outer layers of hydrogen together with helium. Progenitor stars to type Ic supernovas receive got been hard to find. But astronomers sifting through Hubble archival images may receive got uncovered the star that detonated equally supernova 2017ein. The place of the candidate progenitor star is shown inward the pullout box at bottom left, taken inward 2007. The brilliant object inward the box at bottom correct is a close-up icon of the supernova, taken past times Hubble inward 2017, presently later on the stellar blast. NGC 3938 resides 65 1000000 light-years away inward the constellation Ursa Major. The Hubble icon of NGC 3938 was taken inward 2007 [Credit: NASA/ESA/S. Van Dyk (Caltech)/W. Li (University of California)] |
Expectations on the identity of the progenitors of Type Ic supernovas receive got been a puzzle. Astronomers receive got known that the supernovas were deficient inward hydrogen together with helium, together with initially proposed that roughly hefty stars shed this textile inward a strong air current (a flow of charged particles) before they exploded. When they didn't regain the progenitors stars, which should receive got been extremely massive together with bright, they suggested a instant method to attain the exploding stars that involves a couplet of close-orbiting, lower-mass binary stars. In this scenario, the heftier star is stripped of its hydrogen together with helium past times its companion. But the "stripped" star is withal massive plenty to eventually explode equally a Type Ic supernova.
"Disentangling these 2 scenarios for producing Type Ic supernovas impacts our agreement of stellar development together with star formation, including how the masses of stars are distributed when they are born, together with how many stars shape inward interacting binary systems," explained Ori Fox of the Space Telescope Science Institute (STScI) inward Baltimore, Maryland, a fellow member of Van Dyk's team. "And those are questions that non simply astronomers studying supernovas desire to know, but all astronomers are after."
Type Ic supernovas are simply i course of educational activity of exploding star. They concern human relationship for almost twenty per centum of massive stars that explode from the collapse of their cores.
The teams caution that they won't live able to confirm the source's identity until the supernova fades inward almost 2 years. The astronomers promise to role either Hubble or the upcoming NASA James Webb Space Telescope to run across whether the candidate progenitor star has disappeared or has significantly dimmed. They also volition live able to dissever the supernova's lite from that of stars inward its environs to calculate a to a greater extent than accurate measuring of the object's brightness together with mass.
SN 2017ein was discovered inward May 2017 past times Tenagra Observatories inward Arizona. But it took the sudden resolution of Hubble to pinpoint the exact place of the possible source. Van Dyk's squad imaged the immature supernova inward June 2017 with Hubble's Wide Field Camera 3. The astronomers used that icon to pinpoint the candidate progenitor star nestled inward i of the host galaxy's spiral arms inward archival Hubble photos taken inward Dec 2007 past times the Wide Field Planetary Camera 2.
Kilpatrick's grouping also observed the supernova inward June 2017 inward infrared images from i of the 10-meter telescopes at the W. M. Keck Observatory inward Hawaii. The squad together with then analyzed the same archival Hubble photos equally Van Dyk's squad to uncover the possible source.
The Hubble Space Telescope is a projection of international cooperation betwixt NASA together with ESA (European Space Agency). NASA's Goddard Space Flight Center inward Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) inward Baltimore, Maryland, conducts Hubble scientific discipline operations. STScI is operated for NASA past times the Association of Universities for Research inward Astronomy inward Washington, D.C.
Source: NASA/Goddard Space Flight Center [November 15, 2018]
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