Astroboffins have spied the largest star that has gone supernova and it's breaking all the rules Astronomers have stumbled across the strangest supernova left over from the death of a humongous star 200 times as massive as the Sun. It’s the largest known star to have ended its life in a supernova explosion yet. A paper published in the Astrophysical Journal written by a team of researchers led by Harvard University, …
"a humongous star 200 times as massive as the Sun"
If you're going to use a superlative, make sure it's relevant. 200 times greater than the sun is not Humongous.
Antares A is 680 x
KW Sagittarii is 1009 x
and my personal favourite:
UY Scuti is 1708 x (a little under the orbit of Saturn, in comparison). That is humongous.
Perhaps a little parallel reading before you pen such an article?
Anon, as it's a Friday, I'm tired, and have probably made some humongous error in this post.
Actually, the values you give are radii, not masses. Antares A has a mass of 11-14.3 solar masses, and UY Scuti has a mass estimated at 7-10 times that of the sun. If you want something as monstrous as SN2016eit in our galaxy, you need to look at eta Carinae A, which weighs in at an estimated 120-200 solar masses.
Humongous is justified, methinks
What this highlights to me is that despite all the number of scientists and clever people looking at all this stuff, we mere minions on earth actually know bugger all about the Universe in realiaty, and most of the stuff we think we know is theoretical. In the scale of things, we're just amoeba's rolling around in a soup made of ingredients we can't even fathom.
we're just amoeba's rolling around
Amoeba's what? When you use the possessive form of amoeba (that's what the inverted comma does there), the next word needs to be the object that belongs to it. Did you, perhaps think of amoeba's gonads or amoeba's offspring?
If you mean amoeba plural, add the letter e at the end - amoebae. If you find that pretentious or something add a s - without the inverted comma - just like you do with plurals of so many other words - such as cats, ships, planets and astroboffins.
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However, and referencing Muphry's Law, an apostrophe is not an inverted comma. In the days of lead type printers might have used a raised comma, but an inverted and raised comma is something else - it indicates a rough breathing in Greek text. And today the apostrophe is a distinct character anyway.
rolling around in a soup made of ingredients we can't even fathom
But we can fathom it. Not everything by any means, and we may never know what else is out there in our light cone, but we've got a pretty fair understanding regarding most of what we have spotted so far. Some current puzzles will be solved when new information comes to light and some things we think now are explainable by a reasonably sufficient working model will be overturned by new discoveries. The real worry would be if we thought we knew everything or couldn't know anything.
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Scientist and clever person here (I’m published in Nature). If you are not a scientific specialist you have little idea of what is known. Undergraduates have little idea of what is known, you have to do a postgrad research degree to get an inkling.
The point of this article is that we found a star a BILLION light years away (hint a light year is a big number itself) and can measure stuff about it to tell that it’s unusual. Such things are natural experiments. Astronomers and Cosmologists can’t generate universes in bottles under different conditions so they have to find natural experiments like this which they don’t initially understand to advance science.
But the discovery, analysis and ability to tell there’s something interesting here are all impressive achievements requiring advances in many different fields. What can now be done with telescopes with huge diameters made from many widely spaced eyes stitched together by computers is fantastic.
Trials are being done to fly fleets of space telescopes which can keep in extremely tight formation using lasers are being done. They promise being able to image alien planets, not just analyse the light but get pictures. This is not SciFi, it’s almost real Sci.
In Biology we are at the stage where getting genome sequences of every living species and some extinct ones is an achievable process. NZ has a problem with inbreeding and lack of diversity in kakapo, endearing night parrots. There’s a proposal to use CRISPR to introduce variations into their dna based on genomes from dead parrots. Pity we didn’t have that technology when we had more white rhinos or some Galapagos giant tortoises.
The point is we have the tools and understanding to do this. The question is should we and can Maori, who have a say over this, give permission. Human stuff, not some limit of our knowledge. Maori are intelligent and sophisticated people btw. They just view the world slightly differently with differing values.
Because he is making the perfectly valid point that most of what we know is not theoretical - it increasingly has applications - and some of what we know is not applied because people take a decision not to do it. It helps to read the post that started all this.
I'm not so sure about the first bit though. Very few people, I agree, do have a deep knowledge of what it actually means to know something, as distinct from believing or accepting it, and the people who do tend not to go in for politics, where lying can make you PM. But one of my own supervisors used to remark that too much understanding of how knowledge works can be bad for scientists, because what they publish - and are deeply involved in - is itself only partial and may be superseded, and knowing this is the enemy of deciding it is time to publish. In my own career I have had several times to drag results out of people before they thought they were ready, because significant amounts of jobs and money turned on their work.
German kids used to have to read, and sometimes learn, Schiller's Lied von der Glocke:
Das ist’s ja, was den Menschen zieret,/Und dazu ward ihm der Verstand,/Daß er im innern Herzen spüret,/Was er erschafft mit seiner Hand.
(Loosely, "That which adorns man and makes his mind is that he feels in his inmost heart what he creates with his hand")
I think you'll probably end up having to reassess your opinion. What we're seeing is the supernova itself, not the stellar remnant. There is going to be a black hole behind the expanding wavefront we're seeing now. Normally a supernova cools down after a few months but this one has stayed hot for several years, and that's what's interesting about it.
No he won't. If the pair instability model is correct there is very little left of the core of the original star. It is so big the gamma rays cause the core to go kablooie. All that is left is radiation, neutrinos and a rapidly expanding cloud of small pieces. If there is a remnant of core it won't be big enough to form a black hole. They have only found a handful of the things so any observation is likely to throw up a few surprises.
There is going to be a black hole behind the expanding wavefront we're seeing now.
A Pair Instability Supernova is a supernova that doesn't leave behind a black hole or neutron star. The supernova is so violent that it obliterates the core before it can collapse into a black hole, therefore there is nothing left from which a black hole can be formed. Therefore if this is a pair instability supernova, there will not be a black hole.
It's a relatively recent type of supernova.
As an interested layman, 20 years ago the general wisdom that I had heard on dying stars was:
1) red dwarf -> just burns out into a cinder
2) typical star -> planetary nebula -> white dwarf
3) massive star -> supernova -> neutron star
4) really massive star -> supernova -> black hole
But since then, they've added - that I'm aware of - direct collapse black hole (i.e. giant star -> black hole, no supernova at all, sometimes called an 'unnova') and pair-instability supernova that leaves no remnant (except an expanding gas cloud).
When I read it I was thinking Bill & Ted in a science lab.
"Whoa dude, check it out - this star is like totally humongous!"
"Whoa.... wait, do you think our data is maybe ... bogus?"
"No way, its most excellent data!"
"Stellar! Party on supernova!"
Of positrons being the reason for core collapse (and rebound) in a super nova.
https://www.nasa.gov/audience/forstudents/5-8/features/nasa-knows/what-is-a-supernova.html
These kind of utterly un-justified theories kinda toss the rest of what the report says deeply into question, at least for me. It's as if some marketing guy heard a few words and spun a story. Fine for clickbait, not good enough for science.
If there's a whole new theory on what causes supernovas...let's hear it.
The oxygen core burns, everything goes kablooie, anything heavier than oxygen is formed in the supernova.
Depending on the progenitor mass you get different abundances of elements. You might get a shedload of nickel, or you might get a lot of calcium.
This is mostly theory, they haven't seen many of these things, I think this is the first observation they are sure of.
Wondered the same thing. Also 200x the suns mass is, If I remember correctly, essentially the upper limit on stellar mass. Factor in the pair instability which suggests low metalicity, Then this has characteristics of Population 3 stars. That makes this VERY interesting and not just from the behaviour in going nova.
Breaking the rules is good, the data points in this will help tighten existing model theories or force us to throw them away and start again. Either way one step closer.
First I've heardOf positrons being the reason for core collapse (and rebound) in a super nova.
https://www.nasa.gov/audience/forstudents/5-8/features/nasa-knows/what-is-a-supernova.html
Your are not seriously citing a light-weight, simplified for a grade 5-8 audience document as your definitive "this is what a supernova is" source to contradict a paper published in the Astrophysical Journal by Royal Astronomical Society Research Fellows, Post-doctoral fellows, PhDs and PhD students, are you?
I wonder how much hydrogen Earth would need to suck in before ignition happened around it?
And would the resultant forces be sufficient to get the iron/nickel core fusing away?
And if so, would that then blow the hydrogen fusion out?
And if so, would that then result in the iron fusion going out?
To expand on swm’s response: iron can and will fuse in stars, but...
1) you need a whole load of energy flying around before it will start fusing.
2) as noted, it absorbs rather than releases energy and so will actually cool a star down.
IIRC, iron tends mostly to fuse in supernovae because you need those sorts of conditions to force the fusion to happen.
In approximate answer to your question: To ignite fusion, it seems Earth would need to gather more than 80 times the mass of Jupiter in hydrogen. Unfortunately Earth lacks the gravity to do so; argon is the lightest gas it can hold on to, and then only barely. Igniting iron fusion would take several solar masses of hydrogen and a loooong time.
If iron were unstable we would not exist.
In fact it is said that elements like lead are so common because they decay from much heavier ones.
The strange distribution of certain nuclear isotopes is not strange after all.
Incidentally I did find something intriguing: a sufficiently powerful hypernova *might* be an unexplored
way that low mass black holes may be produced, as tiny instabilities in the wavefront.
A big enough core fragment might also collide with another at near relativistic velocities, triggering a black hole
but most of the time it does not thus explaining the anomalously high brightness. Think an H-bomb in a bathtub.
"a dwarf galaxy 54,000 light years away from its center."
Our galaxy is about 52,000 LY in diameter and this nova is almost that far from it's home galaxy centre.
What am I missing? Is the nova not actually in it's home galaxy? If not, and it's a "dwarf" galaxy, then is the nova actually part of that galaxy or orbiting at least a galactic radius outside it?
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