Astronomers get picture of aftermath of a star's double detonation
But a rarer kind of supernova involves a different type of star - a stellar ember called a white dwarf - and a double detonation. Researchers have obtained photographic evidence of this type of supernova for the first time, using the European Southern Observatory's Chile-based Very Large Telescope.
The back-to-back explosions obliterated a white dwarf that had a mass roughly equal to the sun and was located about 160,000 light‑years from Earth in the direction of the constellation Dorado in a galaxy near the Milky Way called the Large Magellanic Cloud. A light-year is the distance light travels in a year, 5.9 trillion miles (9.5 trillion km).
The image shows the scene of the explosion roughly 300 years after it occurred, with two concentric shells of the element calcium moving outward.
This type of explosion, called a Type Ia supernova, would have involved the interaction between a white dwarf and a closely orbiting companion star - either another white dwarf or an unusual star rich in helium - in what is called a binary system.
The primary white dwarf through its gravitational pull would begin to siphon helium from its companion. The helium on the white dwarf's surface at some point would become so hot and dense that it would detonate, producing a shockwave that would compress and ignite the star's underlying core and trigger a second detonation.
"Nothing remains. The white dwarf is completely disrupted," said Priyam Das, a doctoral student in astrophysics at the University of New South Wales Canberra in Australia, lead author of the study published on Wednesday in the journal Nature Astronomy, opens new tab.
"The time delay between the two detonations is essentially set by the time it takes the helium detonation to travel from one pole of the star all the way around to the other. It's only about two seconds," said astrophysicist and study co-author Ivo Seitenzahl, a visiting scientist at the Australian National University in Canberra.
In the more common type of supernova, a remnant of the massive exploded star is left behind in the form of a dense neutron star or a black hole.
The researchers used the Very Large Telescope's Multi-Unit Spectroscopic Explorer, or MUSE, instrument to map the distribution of different chemical elements in the supernova aftermath. Calcium is seen in blue in the image - an outer ring caused by the first detonation and an inner ring by the second.
These two calcium shells represent "the perfect smoking-gun evidence of the double-detonation mechanism," Das said.
"We can call this forensic astronomy - my made-up term - since we are studying the dead remains of stars to understand what caused the death," Das said.
Stars with up to eight times the mass of our sun appear destined to become a white dwarf. They eventually burn up all the hydrogen they use as fuel. Gravity then causes them to collapse and blow off their outer layers in a "red giant" stage, eventually leaving behind a compact core - the white dwarf. The vast majority of these do not explode as supernovas.
While scientists knew of the existence of Type Ia supernovas, there had been no clear visual evidence of such a double detonation until now. Type Ia supernovas are important in terms of celestial chemistry in that they forge heavier elements such as calcium, sulfur and iron.
"This is essential for understanding galactic chemical evolution including the building blocks of planets and life," Das said.
A shell of sulfur also was seen in the new observations of the supernova aftermath.
Iron is a crucial part of Earth's planetary composition and, of course, a component of human red blood cells.
In addition to its scientific importance, the image offers aesthetic value.
"It's beautiful," Seitenzahl said. "We are seeing the birth process of elements in the death of a star. The Big Bang only made hydrogen and helium and lithium. Here we see how calcium, sulfur or iron are made and dispersed back into the host galaxy, a cosmic cycle of matter."
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
The Guardian
3 hours ago
- The Guardian
Nasa discovers interstellar comet moving through solar system
It isn't a bird, it isn't a plane and it certainly isn't Superman – but it does appear to be a visitor from beyond our solar system, according to astronomers who have discovered a new object hurtling through our cosmic neighbourhood. The object, originally called A11pl3Z and now known as 3I/Atlas, was first reported by the Asteroid Terrestrial-impact Last Alert System (Atlas) survey telescope in Rio Hurtado, Chile, on Tuesday. According to Nasa, subsequent analysis of data collected by various telescopes before this date have extended observations back to 14 June; while further observations have also been made. As a result, experts have been plotting the path of the visitor. Now about 416m miles away from the Sun and travelling from the direction of the constellation Sagittarius, the object is believed to be whizzing through the solar system at about 60km/s relative to the sun on a highly eccentric, hyperbolic orbit – suggesting that, like the cigar-shaped object 'Oumuamua that appeared in 2017 and the comet 2I/Borisov that turned up in 2019, it is a visitor from afar. Dr Mark Norris, senior lecturer in astronomy at the University of Central Lancashire, said: 'If confirmed, it will be the third known interstellar object from outside our solar system that we have discovered, providing more evidence that such interstellar wanderers are relatively common in our galaxy.' While the nature of the new visitor was not initially apparent, the Minor Planet Center has revealed that tentative signs of cometary activity have been spotted, noting the object has a marginal coma and short tail. As a result the object has been given the additional name of C/2025 N1. While some experts have suggested the object could be as large as 20km in diameter – bigger than the space rock that wiped out the non-avian dinosaurs – it seems Earth residents don't need to worry. Nasa said: 'The comet poses no threat to Earth and will remain at a distance of at least 1.6 astronomical units [about 150m miles].' It said the object would reach its closest approach to the sun around 30 October, coming within about 130m miles of the star – or just within the orbit of Mars. The comet is then expected to leave this solar system and head back out into the cosmos. Norris said: 'As it gets closer, it's expected to brighten, especially if it turns out to be a comet rather than an asteroid. By the time it makes its closest approach, it will be a relatively easy target for amateur astronomers to observe.' Sign up to First Edition Our morning email breaks down the key stories of the day, telling you what's happening and why it matters after newsletter promotion For those who cannot wait that long, the Virtual Telescope Project, a network of robotic telescopes, is expecting to host a live feed on its YouTube channel from 11pm UK time on Thursday.
Wales Online
6 hours ago
- Wales Online
Scientists baffled by object in space spotted hurtling towards us
Scientists baffled by object in space spotted hurtling towards us The European Space Agency said it has spotted a rocky object, which could be a comet or an asteroid Undated European Southern Observatory handout image of an artistÕs impression showing the first interstellar asteroid: `Oumuamua. (Image: PA ) Scientists have identified an object they suspect may have originated from another star system, and it seems to be heading towards Earth. The European Space Agency (ESA) announced today that its scientists have detected what could be the third extragalactic object ever to venture into the Milky Way. Currently, the harmless object, dubbed A11pl3Z, is several hundred million miles away from Earth, rounding Jupiter. From there, it will accelerate towards Earth, but it won't come anywhere near our planet. Instead, it's expected to visit one of our closest neighbours, Mars. At this stage, officials can't confirm what the object is - it could be a rocky asteroid or an icy comet, both of which are common in our galaxy. For our free daily briefing on the biggest issues facing the nation, sign up to the Wales Matters newsletter here They also can't determine its size or shape. Undated European Southern Observatory handout image of an artistÕs impression showing the first interstellar asteroid: `Oumuamua. (Image: PA ) The ESA plans to conduct further observations to ascertain exactly where A11pl3Z originated from, and NASA, their American counterparts, are also keeping a close eye on the situation, reports the Mirror. Article continues below Astrophysicist Josep Trigo-Rodriguez, from the Institute of Space Sciences near Barcelona, Spain, believes it's an interstellar object based on its unusual trajectory and high speed as it traverses the solar system. In an article for The Conversation, Dr Trigo-Rodriguez discussed A11pl3Z, suggesting "certain aspects of its extended appearance" could indicate the object is a comet. He stated: "There are certain aspects of its extended appearance that could point to it being a comet. The interstellar visitor was first identified by Crimea-based amateur astronomer Gennady Borisov, who spotted the comet using a telescope on August 30. (Image: Creative Commons/Tny873004 ) However, this will need to be confirmed in the coming weeks as it moves deeper into the solar system. He further added: "On the other hand, it is normal for an object subjected to the extremely low temperatures of interstellar space for millions of years to take longer than normal to 'wake up' from its slumber." Dr Trigo-Rodriguez estimates the object's size to be approximately 25 miles (40 kilometres) across and assures that it poses no threat to our planet. "The Scout programme at the Jet Propulsion Laboratory's Centre for the Study of Minor Bodies (CNEOs), has entirely dismissed any risk of a potential Earth impact. The closest the object will approach, according to the programme's estimates, is around 284 million kilometres (just over 176 million miles). The first confirmed interstellar visitor was in 2017. The Milky Way is seen over the Haleakala Observatory and the lights of Kahului, at right, Saturday, Nov. 23, 2024 at the summit of Haleakala National Park near Kula, Hawaii. (Image: AP ) This visitor was named Oumuamua, Hawaiian for scout, in tribute to the observatory in Hawaii that discovered it. Article continues below Initially classified as an asteroid, the elongated Oumuamua has since exhibited signs of being a comet. The second object - and A11pl3Z's direct predecessor - confirmed to have strayed from another star system into our own is 21/Borisov, discovered in 2019 and believed to be a comet.
Reuters
13 hours ago
- Reuters
Astronomers get picture of aftermath of a star's double detonation
WASHINGTON, July 2 (Reuters) - The explosion of a star, called a supernova, is an immensely violent event. It usually involves a star more than eight times the mass of our sun that exhausts its nuclear fuel and undergoes a core collapse, triggering a single powerful explosion. But a rarer kind of supernova involves a different type of star - a stellar ember called a white dwarf - and a double detonation. Researchers have obtained photographic evidence of this type of supernova for the first time, using the European Southern Observatory's Chile-based Very Large Telescope. The back-to-back explosions obliterated a white dwarf that had a mass roughly equal to the sun and was located about 160,000 light‑years from Earth in the direction of the constellation Dorado in a galaxy near the Milky Way called the Large Magellanic Cloud. A light-year is the distance light travels in a year, 5.9 trillion miles (9.5 trillion km). The image shows the scene of the explosion roughly 300 years after it occurred, with two concentric shells of the element calcium moving outward. This type of explosion, called a Type Ia supernova, would have involved the interaction between a white dwarf and a closely orbiting companion star - either another white dwarf or an unusual star rich in helium - in what is called a binary system. The primary white dwarf through its gravitational pull would begin to siphon helium from its companion. The helium on the white dwarf's surface at some point would become so hot and dense that it would detonate, producing a shockwave that would compress and ignite the star's underlying core and trigger a second detonation. "Nothing remains. The white dwarf is completely disrupted," said Priyam Das, a doctoral student in astrophysics at the University of New South Wales Canberra in Australia, lead author of the study published on Wednesday in the journal Nature Astronomy, opens new tab. "The time delay between the two detonations is essentially set by the time it takes the helium detonation to travel from one pole of the star all the way around to the other. It's only about two seconds," said astrophysicist and study co-author Ivo Seitenzahl, a visiting scientist at the Australian National University in Canberra. In the more common type of supernova, a remnant of the massive exploded star is left behind in the form of a dense neutron star or a black hole. The researchers used the Very Large Telescope's Multi-Unit Spectroscopic Explorer, or MUSE, instrument to map the distribution of different chemical elements in the supernova aftermath. Calcium is seen in blue in the image - an outer ring caused by the first detonation and an inner ring by the second. These two calcium shells represent "the perfect smoking-gun evidence of the double-detonation mechanism," Das said. "We can call this forensic astronomy - my made-up term - since we are studying the dead remains of stars to understand what caused the death," Das said. Stars with up to eight times the mass of our sun appear destined to become a white dwarf. They eventually burn up all the hydrogen they use as fuel. Gravity then causes them to collapse and blow off their outer layers in a "red giant" stage, eventually leaving behind a compact core - the white dwarf. The vast majority of these do not explode as supernovas. While scientists knew of the existence of Type Ia supernovas, there had been no clear visual evidence of such a double detonation until now. Type Ia supernovas are important in terms of celestial chemistry in that they forge heavier elements such as calcium, sulfur and iron. "This is essential for understanding galactic chemical evolution including the building blocks of planets and life," Das said. A shell of sulfur also was seen in the new observations of the supernova aftermath. Iron is a crucial part of Earth's planetary composition and, of course, a component of human red blood cells. In addition to its scientific importance, the image offers aesthetic value. "It's beautiful," Seitenzahl said. "We are seeing the birth process of elements in the death of a star. The Big Bang only made hydrogen and helium and lithium. Here we see how calcium, sulfur or iron are made and dispersed back into the host galaxy, a cosmic cycle of matter."
