For the first time, astronomers have observed the final days and death throes of a red supergiant star before its final collapse and massive explosion into a supernova. Supernovas are usually only detected after they happen, although a few of a different type have been caught in the act of exploding.
WASHINGTON, Nov 9 (Reuters) - About 11.5 billion years ago, a distant star roughly 530 times larger than our sun died in a cataclysmic explosion that blew its outer layers of gas into the surrounding cosmos, a supernova documented by astronomers in blow-by-blow detail.
Astronomers Captured The Incredibly Rare Sight of a Star Mere Hours After It Exploded. It's an inconvenient truth of astronomy that nobody gets a personal invitation to witness a star's dying breaths. Catching sight of a star at a critical moment of its demise is a matter of fortune, making it a rare find.
The 1604 event was the last time that a supernova appeared within our Milky Way galaxy. Or at least, the last one known to have been observed; it's possible that there have been other nearby supernovas in the interim, likely obscured by intervening gas and dust.
According to study from a team of researchers from Calvin College in Grand Rapids, Michigan, a binary star system that will likely merge and explode in 2022. This is an historic find, since it will allow astronomers to witness a stellar merger and explosion for the first time in history.
Three different moments in a far-off supernova explosion were captured in a single snapshot by NASA's Hubble Space Telescope. The star exploded more than 11 billion years ago, when the universe was less than a fifth of its current age of 13.8 billion years.
Most of the stars that make up our constellations are just like the sun - they won't ever explode. Only the most massive stars in the universe go supernova. But the 10th brightest star visible from Earth is Betelgeuse, a red supergiant that will indeed end its life with a bang.
Unfortunately, supernovae visible to the naked eye are rare. One occurs in our galaxy every few hundred years, so there is no guarantee you will ever see one in our galaxy in your lifetime. In 1987, a supernova called 1987A was visible in a nearby galaxy called the Large Magellanic Cloud.
So, how long does a supernova take to explode? A few million years for the star to die, less than a quarter of a second for its core to collapse, a few hours for the shockwave to reach the surface of the star, a few months to brighten, and then just few years to fade away.
The most recent supernova to be seen in the Milky Way galaxy was SN 1604, which was observed on October 9, 1604. Several people, including Johannes van Heeck, noted the sudden appearance of this star, but it was Johannes Kepler who became noted for his systematic study of the object itself.
No. While none exist to date it would be possible for a dead star to have cooled to a safe temperature.
An explosion of a nearby star might leave Earth and its surface and ocean life relatively intact. But any relatively nearby explosion would still shower us with gamma rays and other high-energy radiation. This radiation could cause mutations in earthly life.
Generally, the more massive the star, the faster it burns up its fuel supply, and the shorter its life. The most massive stars can burn out and explode in a supernova after only a few million years of fusion. A star with a mass like the Sun, on the other hand, can continue fusing hydrogen for about 10 billion years.
We estimate at about 100 billion the number of galaxies in the observable Universe, therefore there are about 100 billion stars being born and dying each year, which corresponds to about 275 million per day, in the whole observable Universe.
Most stars take millions of years to die. When a star like the Sun has burned all of its hydrogen fuel, it expands to become a red giant. This may be millions of kilometres across - big enough to swallow the planets Mercury and Venus.
The red supergiant Betelgeuse, a colossal star in the Orion constellation, experienced a massive stellar eruption – the likes of which have never been seen before, according to astronomers.
Betelgeuse is about 750 times the radius of our Sun and 530 light-years away, which is well beyond the 50 light-year “danger zone” for Earth if a nearby star does go supernova. Of course, Betelgeuse may have already gone supernova over 529 years ago and its light just hasn't reached us yet.
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.
Will the Betelgeuse supernova destroy Earth? No. Whenever Betelgeuse does blow up, our planet Earth is too far away for this explosion to harm, much less destroy, life on Earth. Astrophysicists say we'd have to be within 50 light-years of a supernova for it to harm us.
After the star's outer layer has escaped, the much smaller inner layer collapses into a white dwarf. This star, which is hotter and brighter than the red giant it came from, illuminates and warms the escaped gas, until the gas starts glowing by itself – and we see a planetary nebula.
Our sun isn't massive enough to trigger a stellar explosion, called a supernova, when it dies, and it will never become a black hole either. In order to create a supernova, a star needs about 10 times the mass of our sun.
Light does not require a medium to travel through but sound requires a medium, so it cannot be transmitted through space. That is why we are able to see the supernova explosions but cannot hear them. Was this answer helpful?
These observations weren't easy. The moon is a difficult target for Hubble because it moves across the sky faster than Hubble can track it and is very dim in ultraviolet light.
Scientists believe the gravity of Planet Nine could be shepherding space rocks into those orbits. HD 106906 b orbits so far from the binary stars at the heart of its solar system that Hubble can image it directly (see above). This allowed the team to understand its orbit, which is about 15,000 year years long.
Once there is no fuel left, the star collapses and the outer layers explode as a 'supernova'. What's left over after a supernova explosion is a 'neutron star' – the collapsed core of the star – or, if there's sufficient mass, a black hole.