[ad_1]
This artist's concept has a star-shaped supernova progenitor 2017ein-a blue supergiant star that appeared in a spiral galaxy NGC 3938, located 65 million light-years away. It would have exploded as a supernova in 2017. Credit: NASA, ESA, and J. Olmsted (STScI)
Supernovas are the deathly explosions of massive stars. One of the ways that astronomers look for clues about how these stars are going to get you going for starvation. They comb through archival telescope images and try to pinpoint the location and identity of the star before it blasted apart. Now, for the first time, a known type of "type Ic" (pronounced "one-C"). Of all the classes of supernovae, this is the only one that has been known to be of a character of a Holy Grail by astronomers.
The type Ic supernova, called SN 2017ein, was first discovered in May 2017 by researchers using the Tenagra Observatories in Arizona. It is located in a spiral galaxy called NGC 3938, about 65 million light-years away. The caltech astronomy team was able to track down this supernova's progenitor using archival images from NASA's Hubble Space Telescope, taken in 2007.
"Says Schuyler Van Dyk, a staff scientist at IPAC, a science and data center for astronomy at Caltech. "You can not sleep that day and have to mobilize to try to find the explosion. A few weeks after the supernova was discovered, we found a candidate in both the new and archival Hubble images. "Van Dyk is lead author of a paper on the findings, published this summer in The Astrophysical Journal. "The new images were essential for pinpointing the candidate's progenitor's location."
The progenitor is hot and luminous and is thought to be a single star 48 or 49 times the mass of our sun or a massive binary star system in which the stars are exploded weighing between 60 and 80 solar masses.
"Type Ic supernovas occur with the most massive of stars," says Van Dyk. "But we were surprised by how massive this one appears to be, and especially by the possibility of a massive double-star system as the progenitor. Although theories have existed for the last three decades, it could have been the explosion of massive single stars, alternative, more recent theories point to stars of lower mass in binary systems as being the origins of these explosions. "
Other supernova classes include type Ia, which occur when white dwarfs in binary star systems explode (cosmologists used these to discover that our universe is not only expanding but accelerating apart). Type II, type Ib, and supernovas Ic occur when massive stars collapse at the end of their lives, forming neutron stars or black holes. Type Ib and Ic differ from type II in their progenitor stars in their central cores before exploding. Type Ib and Ic supernovas differ from each other slightly in chemical composition.
These two types of supernova are the most important features in the world.
"The origins of such explosions are falling to the entire astronomical community, not just supernova researchers," says Ori Fox from the Space Telescope Science Institute (STScI), co-authored on the study. "The results have implications on ideas from star formation to stellar evolution and feedback into the galaxy."
"Astronomers have been trying to find this progenitor for some 20 years," Van Dyk says. "Humans would not be here without supernovas-they make the chemical elements from which we are made."
The astronomers say that they should be able to confirm that they have identified the correct type of explosion within a few years, using Hubble or the upcoming NASA James Webb Space Telescope, set to launch in 2021. As the supernova fades as expected, the astronomers will have a clear view of the area around it. If the luminous progenitor candidate is correctly identified in archival images, then it will have vanished and should not be seen in the new images. If the scientists still see the nominee, that has been misidentified and some other hidden star has the culprit.
The study, titled, "SN 2017ein and the Possible First Identification of a Type IC Supernova Progenitor," was funded by NASA, the National Science Foundation, the Tabasgo Foundation, the Christopher R. Redlich Fund, and the Miller Institute for Basic Research. Science.
[ad_2]
Source link
