Has NASA seen a supernova?
NASA’s James Webb Space Telescope has observed a supernova that exploded when the universe was only 730 million years old — the earliest detection of its kind to date. Webb’s crisp near-infrared images also allowed astronomers to locate the supernova’s faint host galaxy. In 1987, Supernova 1987A in the Large Magellanic Cloud was observed within hours of its light reaching the Earth.No further supernovae have since been observed with certainty in the Milky Way, though many others outside the galaxy have been seen since S Andromedae in 1885. SN 1987A in the Large Magellanic Cloud was visible to the naked eye at night.
Is supernova a dying star?
When it runs out of its last source of fuel, the nuclear engine starts sputtering. For massive stars this marks the beginning of a supernova: the core of the dying star collapses, the mass shells around fall onto it and bounce off. About 4 to 7 billion years from now, when hydrogen fusion in the Sun’s core diminishes to the point where the Sun is no longer in hydrostatic equilibrium, its core will undergo a marked increase in density and temperature which will cause its outer layers to expand, eventually transforming the Sun into a red giant.When the Sun exhausts its store of nuclear fuel, some 5 billion years from now, it will evolve into a bloated red giant, gobbling up Mercury and Venus, and scorching the Earth. After ejecting its outer layers in the form of a colourful planetary nebula, the Sun will then be compressed into a tiny white dwarf star.
Can our sun go supernova?
No supernova or black hole Our sun isn’t massive enough to trigger a dramatic stellar explosion, known as a supernova, when it dies — and it won’t ever become a black hole, either. Supernovae are the most powerful and energetic explosions in the universe. In a single moment, they release more energy than our Sun will over its entire life — equivalent to several octillion nuclear warheads going off all at once.After the supernova, anything left of the star is squashed and compacted into an incredibly small, dense object. This is the black hole. Once a black hole has formed, it grows by pulling in gas, dust, stars, and even other black holes around it.A nova is a sudden, short-lived explosion from a compact star not much larger than Earth.A hypernova is a very energetic supernova which is believed to result from an extreme core collapse scenario.One possibility is that supernova explosions of massive stars in the early Universe formed stellar-mass black holes that, over billions of years, grew supermassive. A single stellar-mass black hole can grow rapidly by consuming nearby stars and gas, often in plentiful supply near the galaxy center.
What exactly is a supernova?
A supernova is the colossal explosion of a star. Scientists have identified several types of supernova. One type, called a “core-collapse” supernova, occurs in the last stage in the life of massive stars that are at least eight times larger than our Sun. A supernova typically lasts for several weeks to a few months. The initial explosion occurs within seconds, but the afterglow and energy release can be observed for an extended period as the ejected material expands and interacts with the surrounding environment.If a supernova explosion were to occur within about 25 light-years of Earth, our planet would probably lose its atmosphere, and all life would perish. However, astronomers haven’t found any dangerous supernova candidates in our cosmic backyard, so there’s no reason to worry.Mainstream media reports discussed speculation that Betelgeuse might be about to explode as a supernova, but astronomers note that the supernova is expected to occur within approximately the next 100,000 years and is thus unlikely to be imminent.
What’s worse than a supernova?
Hypernovae are thought to be supernovae with ejecta having a kinetic energy larger than about 1045 joule, an order of magnitude higher than a typical core collapse supernova. The ejected nickel masses are large and the ejection velocity up to 99% of the speed of light. A hypernova — sometimes called a collapsar — is a particularly energetic core-collapse supernova. Scientists think a hypernova occurs when stars more than 30 times the mass of the Sun quickly collapse into a black hole. The resulting explosion is 10 to 100 times more powerful than a supernova.