Eta Carinae, Soon To Be a Local Supernova

da4 writes "Phil Plait over at Bad Astronomy has a great article about Eta Car, a star approx 7,500 light years away from us that's ready to supernova sometime Real Soon Now." Larger versions of the Hubble-Chandra image of Eta Car are available at the Chandra site. Of course when astronomers say it's "about to explode," they really mean it probably exploded 6,500 to 7,500 years ago and we're awaiting the news.

Comments

Schroedingers Nova?

[kylben]

If we never get the news, will it actually have exploded, or not?

Re:Schroedingers Nova?

[Kagura]

Way to fall into the editor's trap, trying to spur spurious discussion about whether events outside our lightcone actually happened before they intersected our lightcone. The editors may feel we need help in starting a discussion on many stories.

Re:Schroedingers Nova?

[geekoid]

Don't think you are so important that nothing happens unless you observe it, earthman.

Bad Astronomy?

[sczimme]

I don't know if we should take the word of someone who runs a site called 'Bad Astronomy'...

*checks TFA*

The blue part is an optical image from Hubble, and shows the bipolar lobes of gas ejected when Eta Car had a coughing fit back in the 1840s. That's 20 octillion tons of gas (20,000,000,000,000,000,000,000,000,000) it ejected at about a million miles per hour, in case you're not getting enough awesome in your diet.

I withdraw the objection. :-)

Re:Bad Astronomy?

[spun]

The Bad Astronomy site started out to debunk nutty astronomical theories, like the Electric Universe theory, or the preposterous notion that the moon landing was faked. It's a pretty decent site.

Re:Bad Astronomy?

[Fission86]

This conveniently ignores the fact that Einstein never even mentioned electrodynamics, except in his correspondence with (that expletive) V, and that James Clerk Maxwell demonstrated that e-fields and b-fields are inseparable.

I hate to tell you this dude, but Einstein wrote a little paper called "On the Electodynamics of Moving Bodies" perhaps you've heard of it?

Also, Maxwell never said electric fields and magnetic fields were INSEPERABLE, just that they were connected

Astrophysics continues to be the only field of science where magnetic fields are treated as if they are independent entities that can exist in the absence of electric currents and electric fields.

Also, the reason electric fields can be thought of independantly from magnetic fields, on an astrophysical scale, is that electric fields can extend infinitely from an electric monopole and magnetic fields must return to their source, which i might add has no monopole associated. Pick up an E&M book (i suggest Griffith's, it's pretty good), you might learn what Maxwell's equations actually mean.

People would be wise to consider that it is now an established fact that there exists an interstellar magnetic field whose origin remains unknown.

I'd like to see how you prove that while staying on this planet/in this solar system.

It's interesting that the site is called "Bad Astronomy" -- as if all discussion on that site is meant purely to confirm existing mainstream theories.

Every time someone starts talking about an alternate theory of physics they always have the exact same reaction when people don't believe them "oh, you're a fool for trusting the old ways, blah blah blah." There's a reason these theories are mainstream, they're testable and retestable.

Theories are not evaluated on the basis of their merit alone, but rather how well their creators can withstand a relentless series of withering attacks.

Yes, you are correct, but this is the way of doing things, since nothing can ever be absolutely proven within a finite amount of time (see universe time scale of infinity), a good bet of what is most probable is the best we can ever hope for. And a relentless attack on theories is a good way to do this, if a theory is found lacking, it might be completely wrong or just in need of a tweak. Currently the Standard Model is in one of these categories as it unifies the strong nuclear, weak nuclear and electromagnetic forces, where as gravity is unadressed. And string theory might just be in the other (it's untestable, thus cannot be proven or disproven), but that's another story all-together.

Re:Bad Astronomy?

[The Master Control P]

Eh, I'm up for some shits'n'giggles and I've got some time to pass. Of course, the fact that I disagree is certain proof that I am part of "the conspiracy" which is defined as anyone who thinks you're wrong and refuses to immediately acknowledge your obvious correctness.

Arguing that arguments that are not peer-reviewed by mainstream astrophysicists do not count is disingenuous. People who have staked their careers on the mainstream theories will resist every attempt at disruptive paradigm shifts.

Right. The guy who comes up with proof that one of our most basic theories is erroneous will be hated. He most certainly will not be one of the most celebrated scientists of all time like Einstein, and he most definitely will not win a Nobel prize for his insights. Because scientists hate discovering new and remarkable things they didn't know about before. History is full of scientists like John Levy, whose work on asteroid impacts was supressed by The Establishment even after he presented clear and convincing evidence that he was correct... No, wait, asteroid impacts are in every geology and astronomy book today.

The announcement made by the Sudbury Neutrino Observatory (SNO) that the SNO detector has the capability to determine whether solar neutrinos are changing their type en route to Earth is false on its face. There is no way that measurements made at only one end (here on Earth) of a transmission channel (that stretches from the Suns center to Earth) can reveal changes that occur farther up the channel (say, within the Sun itself, or near Mercury or Venus).

Consider a freight train that runs from New York to Chicago. We live in Chicago and are only able to observe the train as it arrives in Chicago. It pulls in with 4 freight cars, 2 tank cars, and 1 flat car. How is it possible, no matter how sophisticated our method of observation, for us to make any conclusions whatever about whether freight cars, tank cars, or flat cars have been added to or subtracted from the train at, say, Cleveland? Moreover, how is it possible to say that freight cars have turned into tank cars or flat cars along the route somewhere?

Horray for superficially plausible but completely incorrect analogies. Regardless of whatever happens to neutrinos on their way to earth, they can't simply disappear. Your analogy is simply wrong, because we do know that matter-energy was not added or lost in the neutrino stream, because neutrinos don't interact with squat. So now, we think we know what the train was like when it left. We know nothing was added or lost, yet the cars aren't what we expected. Is the logical conclusion that the neutrino waveforms changed or that it's all a giant conspiracy?

Sustained nuclear fusion using extreme heat and pressure is a Will-O-the-Wisp (literal meaning - fools fire) that has been desperately sought after for over 50 years. It has never been obtained in any laboratory. Its existence in the Suns core is nothing more than a proclaimed hypothesis. We cannot see into the Sun. We cannot observe what is occurring below the photosphere. The Electric Sun model does indeed include the probability that empirically confirmed nuclear fusion is occurring near the surface of the Sun.

Let me make sure I've got this right... you're comparing the conditions in experimental fusion reactors to those which exist in the core of a star? And then saying that since our fusion reactors don't work, starfusion doesn't work? I'm afraid there are some minor differences, like the fact that the core of a star is compacted to twenty times the density of lead by gravity. There's also the basic fact that energy loss is proportional to area and fusion output to volume, which puts our tiny reactors at a slight disadvantage.

Either you truly don't know these things about fusion physics, which casts doubt on how much else you don't know, or you are intentionally ignoring them.

Re:Bad Astronomy?

[RespekMyAthorati]

It's obvious to most of us who made it past grade school that it was a fake.

It's obvious to anyone who actually paid attention in grade school that these "anomalies" have all been explained, although most of them never needed to be. Only an idiot would have any trouble seeing through "anomalies" like "the images are too perfect" (they are far from perfect) or "who took the the picture of Neil Armstrong on the ladder" (the camera was mounted on the lander's base).

Lord, deliver us from morons like you.

thanks

[stoolpigeon]

Of course when astronomers say it's "about to explode," they really mean it probably exploded 6,500 to 7,500 years ago and we're awaiting the news.
 
could you clear up that 'sun rise' and 'sun set' thing for me as well?

Re:thanks

[IcyNeko]

Sunrise, sunset. Sunrise, sunset. Swiftly flow the days. Seedlings turn overnight to sunflowers, blossoming even as we gaze.

I hope this clears up any further questions.

Re:thanks

[HTH NE1]

Of course when astronomers say it's "about to explode," they really mean it probably exploded 6,500 to 7,500 years ago and we're awaiting the news.

could you clear up that 'sun rise' and 'sun set' thing for me as well?

How about this: even though this expected supernova happened thousands of years ago, for all causal purposes, it won't have any effect upon us until we can see it. After all, the speed of light is really just the speed of causality.

So, in a local causal sense, it hasn't happened yet. The distance just means that if we thought to have any influence on it before it happens here, we'd have to have done something thousands of years ago or longer to exert a causal influence.

Don't hold your breath

[MarsDefenseMinister]

We could be waiting to see this supernova theoretically about as long as the pyramids have been standing over the sands of Egypt.

Re:Don't hold your breath

[ozzee]

Which is an interesting statement, really, since it presupposes some sort of universal timeline on which it has "already" gone supernova. When in fact, there is no universal synchronicity.

Does that mean that cat I ran over last night in my car was not necessarily born yet so I didn't really run over it ? Phew, I was having a bit of a guilt trip....

Re:Don't hold your breath

[IWannaBeAnAC]

Argh, I was going to moderate this thread, but when I saw this post I felt I should reply instead.

Eta C surely has gone supernova already. General relativity tells us that the passage of time depends on your movements in space, but it doesn't forbit the presence of some 'special' reference frame in which one can consistently give an age on events that happen in the universe. That special reference frame would be the one based on the center of the universe - in effect, the center of mass frame. But even without such a special frame, we can certainly give a precise timeline between any two events no matter how separated they are or how they move. General relativity allows the exact calculation, it just won't be a constant timeline with time moving at the same rate for all observers.

For the case of Eta C, it is located at a distance of 7500 lightyears away, so the light we see from it now left Eta C 7500 years ago. Since we will surely see it go supernova sometime within the next 1000 years, there is no doubt at all that Eta C went supernova sometime between 6500 and 7500 years ago. General relativity doesn't even come into it, it is already clear just from the finite velocity of light.

Re:Don't hold your breath

[IWannaBeAnAC]

You should RTFA. It is almost at the end of the stellar lifecycle, and has already used up all of its hydrogen. If we don't see it go nova sometime within the next 1000 years, then our theories of stellar evolution are seriously f*cked.

Re:Don't hold your breath

[IWannaBeAnAC]

The timespan isn't millions of years; the time since the star started shedding nitrogen is only a few hundred years (? I can't be bothered going back to the article - but anyway it is much less than millions).

for a slightly sick analogy, predicting the lifetime of a child at birth is hard to do with any accuracy. Predicting the lifetime of someone dying of cancer is much easier ;-)

Gamma Rays

[turgid]

So, do I need to build a lead-lined concrete bunker in my garden?

Re:Gamma Rays

[kungfoofairy]

According to TFA, it's tilted 40 degrees away from us so we won't get hit.

Re:Gamma Rays

[niceone]

So, do I need to build a lead-lined concrete bunker in my garden?

You don't have a lead-lined bunker in your garden already? You must be new around here.

Re:Gamma Rays

[PieSquared]

Stars rotate on an axis. I'm not an astrophysicist, but I'd assume that most of the radiation and gasses would go either in the direction of the axis or in the plane perpendicular to it. I mean, there is a *huge* amount of angular momentum that has to be preserved when you consider mass and the speed of rotation.

So yea, kinda like the death star explosion in the remake. Or maybe perpendicular to that. Once again, not an astrophysicist.

Re:Gamma Rays

[kenaaker]

The lobes in the picture show the path followed by the material from previous outbursts. That material is guided by the magnetic field around the star, to the axis of rotation of the magnetic field, which generally lines up with the axis of rotation of the star. Because of the angular momentum of the star, it should maintain that orientation and any new outbursts should go in the same direction as the previous burst.

Re:Gamma Rays

[Intron]

Note that the lobes appear to be tilted away from us by about 40 degrees or so. That's a good thing. When stars like Eta Carinae explode, they tend to shoot of beams of energy and matter that, at its distance of 7500 light years, could kill every living thing on Earth. But since it's pointed away from us, all we'll get is a spectacular light show.

Matter won't get here for quite a while, but the X-Rays, etc. will get here at the same time as the pretty light. For the energy to be enough to kill us at 7500 light years, and the inverse square law to be in effect, that means the energy density at the star's surface would be ... hmmm ... fairly large.

Re:Gamma Rays

[rubycodez]

but it is funny how astonomers say the explosion will "probably" go along the axis of rotation as the previous 19th century "belch" did (see wikipedia or nasa's web page). If "probably" is true, then things outside our atmosphere get fried, like sattelites, astrounauts on missions, etc. No big deal. But suppose that thing blows spherically, then the gamma dose will be many times greater and you'll be wanting a lead jock strap if you're male.

Re:Gamma Rays

[secPM_MS]

There is good reason to believe that eta carniae will emit a powerfull gamma ray burst when it collapses. Since the axis of rotation is not pointed anywhere near us, we are at no risk from the gamma beam. It is also possible that it is massive enough to suffer a pair creation supernovae. A recent supernovae of this type in a presumed LBV (luminus blue variable) was ~ 100 X brighter than most core collapse supernovae. Regardless, it is to far away from us to create any type of radiation hazard or even cause problems with perturbing the day - night balance.

Re:Gamma Rays

[The Bad Astronomer]

There are several forces that direct the outflow of an explosion. In this case, it's the rotation of the star coupled with its magnetic fields. When the core collapses, it forms a black hole. The inner parts of the star collapse down too, forming a flattened disk around the BH. The disk rotates quickly, and has ferocious magnetic fields. It's also incredibly hot. This forces material outward, along the poles of the disk. Two beams of energy and matter erupt out, forming what we call a gamma-ray burst. We're pretty sure this will be along the same axis as those two lobes which blew out in the 1800s. So they'll miss us. If the star explodes as a regular old supernova, it's too far away to do any damage; they have to be withing about 100 light years to harm us. I have references for all this, but I won't list them here. I'm writing a chapter in my next book about it... :-)

Re:Gamma Rays

[The Bad Astronomer]

Oh, I prefer vodka or tequila, but the point is still true. :) It's not so much that we talk conservatively, as it is that people tend to tale whatever small thing you say and run with it. At least in my case that's true! I try to lay things out pretty clearly if I can. I think Eta has maybe a few hundred years left before it blows, tops, but others might give it longer. The point is, *we don't know*. But it'll be cool when it does explode. Woohoo!

Relative Time

[profplump]

Apparently da4 discovered some new non-relative timescale that's consistent throughout the universe without respect to position or velocity. That seems much more noteworthy than this supernova thing.

Ummm...

[TheSHAD0W]

All I can say is, if you see Al Gore, Michael Moore and Noam Chomsky wearing robes and riding camels... run like hell.

Re:Ummm...

[rossz]

That was funny. If I had any moderation points left I would have given you one.

When will it explode?

[dfn5]

they really mean it probably exploded 6,500 to 7,500 years ago and we're awaiting the news.

When?
Now.
Now?
Now.
I can't
Why?
We missed it.
When?
Just now.
When will then be now?
Soon!

Re:If we detected it today. . .

[SpryGuy]

A few nights of having a star in the night sky that is brighter than the moon, perhaps?

And lets not forget all the religious fanatics taking it as a sign, and panicking, and causing social unrest or upheaval around the globe.

I hope no one died.

[0p7imu5_P2im3]

I just hope that any local civilizations had advanced far enough to escape that horrible fate.

At the rate we're going, what with news of Congress living up to their name (opposite of progress) with regard to exploration the exploration of Mars, we won't escape the fate of our solar system.

Re:I hope no one died.

[spun]

Eta Carinae is so large, it is almost too big to be a star. It has been blowing itself apart every now and then since it was born. I find it unlikely in the extreme that any life could have developed nearby. I doubt the system even has planets.

Re:Neutron emissions

[WrongMonkey]

Note that the lobes appear to be tilted away from us by about 40 degrees or so. That's a good thing. When stars like Eta Carinae explode, they tend to shoot of beams of energy and matter that, at its distance of 7500 light years, could kill every living thing on Earth. But since it's pointed away from us, all we'll get is a spectacular light show. It could potentially wipe out life on Earth, but its pointed in the wrong direction...hopefully.

Re:If we detected it today. . .

[Chris Burke]

You may be thinking of SN 1006, the brightest supernova in recorded history. It was significantly brighter than Venus, though not as bright as the moon. It was bright enough to be easily seen during the day, and was bright enough to read by at night. This event was documented in Chinese, Egyptian, Middle Eastern, Swiss, and even North Americans records, as one would expect of something so amazing. Yet it is conspicuously absent from any other European writings, and the common story (i.e. i can't coroborate at all, may be apocryphal) is that the Church and their "perfect unchanging universe" doctrine made it heresy to even acknowledge that the thing was even there.

Or, maybe you're thinking of SN 1054, which according to Wikipedia may have been described by Irish monastic monks, but was later corrupted into a story of the Antichrist.

Re:How fast are the gamma rays moving?

[spun]

Let me introduce you to a thing called the Internet. You can use it to look up facts and dispel ignorance. Well, I can use it that way, anyhow. Evidently you can't. Here you go: http://en.wikipedia.org/wiki/Gamma_radiation

In short, gamma radiation is light. Just very, very high frequency light.

It's all Carter's fault

[FrostedWheat]

"You know, you blow up one sun and suddenly everyone expects you to walk on water."

Real Soon Now

[Jugalator]

Keep in mind that on a cosmolical scale, that could be within 10,000 years or so, a few nuclear wars and greenhouse disasters later. ;-)

Seeing Eta Carinae for yourself

[spaceyhackerlady]

The southern hemisphere sky has lots of goodies that us northern types don't get to see, and the Eta Carinae region is one of them. The nebula is slightly larger than the Orion Nebula as seen from Earth, but slightly dimmer. To me it looks like a flower blooming in space. It is accompanied by zillions of other nebulae and star clusters.

The Milky Way through Centaurus and Carina is why astronomers often go to places like Australia for their vacations. I've taken a telescope to Costa Rica several times myself, and while the view isn't as good as it is in Australia, it's a lot less travel. The only thing we really miss out on from Costa Rica are the Magellanic Clouds, which look far better from New South Wales than they do from Guanacaste. The vague smudges down at the Tico horizon are detached pieces of the Milky Way in the Aussie country sky.

My first view of the Eta Carinae region was with binoculars from St. Kilda Beach in Melbourne. It's not something one quickly forgets.

...laura

Bipolar Symmetric Objects

[pln2bz]

There's something that doesn't quite follow with this article. The article states that we are only in danger when the bipolar configuration faces us. However, when the bipolar morphology faces us, it will look just like a sphere. The other lobe will be obstructed by the one closest to us. Somebody please correct me if I'm wrong, but how often do we see spherical objects in space as being identified as a bipolar configuration pointing at us?

Couldn't a person make a pretty convincing argument that the bipolar configuration is in fact the primary configuration of all such objects, and that anything that looks like a sphere to us is in fact just the bipolar configuration pointing at us?

Re:Bipolar Symmetric Objects

[The Bad Astronomer]

That's an astute question. Perfect spheres are hard to come by in astronomy, though they're out there (Abell 39 is probably the best example: http://antwrp.gsfc.nasa.gov/apod/image/0101/abell3 9_wiyn_big.jpg). The famous Ring Nebula (http://antwrp.gsfc.nasa.gov/apod/ap060625.html) is an object that people thought was a ring, but it turns out to be barrel-shaped and pointed at us. That happened a lot. Bipolar objects are very common, since lots of objects either spin or have disks, which shapes the outflow into two lobes of some kind.

What makes you tick, pln2bz?

[spun]

You know, I've read your Electric Universe arguments here many times before, and I'm curious. What's your background? What drew you to the EU theory?

I'll tell you the problem I have with the theory, it's the whole, "There is no fusion in stars, it's all electric!" thing. Certainly we don't know everything there is to know about plasma, and certainly the mainstream theories do not have everything nailed down, but come on! The science behind star fusion is so interwoven with all of modern knowledge and technology that if something as major as EU were true, almost everything else we know would have to be false, and all our technology would be very different.

The thing is, the Electric Universe folks make an extraordinary claim. Extraordinary claims require extraordinary proof. If anyone in the EU community had that proof, they would be world famous rather than the marginalized outcasts they are. It's not like there haven't been MAJOR scientific revolutions in the past, it's just that THOSE guys had incontrovertible hard data to back them up.

At first I thought you might just be a clever troll, but your tenacity on this subject goes far beyond the casual interests of a troll. I think you really believe all this, and rather than make me think you are an idiot, which you clearly are not, it makes me very curious about what makes you tick.

Re:What makes you tick, pln2bz?

[pln2bz]

Hey, it's my old friend! The memories ... ;)

The real issue at hand here is that the mainstream astrophysicists and enthusiasts today refuse to seriously consider the legitimate issues that Electric Universe Theory proposes. There is so little awareness on the mainstream side that the group as a whole is completely oblivious when an EU Theory is even validated -- which happens far more often than is being accepted. In order to confirm or deny a theory, it's important to first fully digest it. Even if the materials do not meet your typical requirements for mathematics, that does not necessarily imply that they are inherently false and unworthy of consideration. They are still ideas.

This constant insistence on peer review studies is a bit of a cop-out. It is really more of an excuse to prevent consideration of the theory by people who have come to depend upon the status quo. There are plenty of rather simple laboratory experiments that can validate the concept of electrical terra-forming -- especially with respect to Mars. I can go through the list, but few mainstreamers want to even hear about it.

The theory of uniformitarianism is slowly trending out of fashion. It's becoming increasingly acceptable within mainstream geology and archaeology circles that some sort of violent process could have occurred within human history. In other words, catastrophism is gradually being co-opted by the mainstream -- but without any consideration of plasmas, contacting plasma spheres or electrical interactions. It's generally thought that impacts are really just physical collisions, which lead to explosions. But there have been few attempts to actually demonstrate this by inducing an impact of some sort. The one attempt at an impact that has occurred -- the Deep Impact mission -- seemed to suggest a pre-impact flash that would correspond with the conjunction of two plasma spheres. But since other explanations exist, the mainstream astrophysicists gravitate to those other explanations. Rather than follow the anomalous data in an objective manner, they spend more time attempting to conform the data to mainstream theories.

If EU Theory wasn't true, then it would eventually become clear during the course of researching it. However, the sheer number of supportive details suggests that it likely is true. The more I read about it, the more this picture gets filled in. There are certainly gaps in the understanding and mathematical clarity, but there are no anomalies in EU Theory as there are within the mainstream circles. You will surely argue that this is because it's not a mature theory at this point in time, but that's not the point. The theory as a whole works quite well -- oftentimes better than the mainstream theories. There are actually many things that EU Theory explains that the mainstream theories avoid like the plague.

The idea that EU Theory says that there is no fusion occurring on stars is btw false. From http://www.electric-cosmos.org/sun.htm:

The z-pinch effect of high intensity, parallel current filaments in an arc plasma is very strong. Whatever nuclear fusion is taking place on the Sun is occurring here in the double layer (DL) at the top of the photosphere (not deep within the core). The result of this fusion process are the "metals" that give rise to absorption lines in the Sun's spectrum. Traces of sixty eight of the ninety two natural elements are found in the Sun's atmosphere. Most of the radio frequency noise emitted by the Sun emanates from this region. Radio noise is a well known property of DLs. The electrical power available to be delivered to the plasma at any point is the product of the E-field (Volts per meter) times current density (Amps per square meter). This multiplication operation yields Watts per cubic meter. The current density is relatively constant over the height of the photospheric / chromospheric layers. However, the E-field is by fa

Re:What makes you tick, pln2bz?

[Cheapy]

"Extraordinary claims require extraordinary proof."

I think any theory on the universe's nature would require extraordinary proof. My theory? Turtles, man. Turtles all the way down.

Re:What makes you tick, pln2bz?

[Short Circuit]

If fusion occurs where and how your sources says it is, it should be a simple matter to perform a laboratory-condition demonstration of this effect. If you can demonstrate fusion without the temperatures found at the center of the sun, I might be less disinclined to believe the EU concept.

Don't tell me none of the labs will touch it, though. At the very least, The EU folks should be capable of annoying "mainstream" scientists enough that some mainstream scientist would perform the experiment. Quantum mechanics annoyed Einstein and other physicists sufficiently that they came up with a thought experiment intended to discredit QM.

If such a thought experiment can be turned in favor of QM because of QM's merit (see a Slashdot article from last week or the week before about "spooky action at a distance"), then surely, if EU has merit, experiments intended to disprove EU can be turned in EU's favor.

Come back when that happens. If it already has happened, provide links to and/or names of actual papers, not more sites that describe the theory in layman's terms. Basing arguments on layman's terminology is disingenuous; An analogy can never be more true than the evidence.

Re:Eta C is not 7500 light years away for me

[IWannaBeAnAC]

No, even in that case Eta C has already gone supernova. It might only take you one day to get to Eta C in your frame of reference, but in the frame of reference of Eta C (or the frame of reference of the Earth, for that matter) it will take very close to 7,500 years. Since it already went nova at least 6,500 years ago, you will be at least 14,000 years too late if you wanted to see it up close.

The mainstream is not objective?

[mangu]

they stack the cards very heavily in favor of mainstream theories. There is absolutely no attempt at objectivity.

So, you think that theories that are widely accepted by the experts in the field are less objective than those theories that are accepted by their creators alone? An interesting definition, I wonder what would you call a "subjective" theory...

Theories are not evaluated on the basis of their merit alone, but rather how well their creators can withstand a relentless series of withering attacks.

Psst, I have some bad news for you. The "merit" of a theory could be very well *defined* as how it can whitstand a relentless series of withering attacks. If it cannot do that, it has no merit. Any scientist pretty much expects to have every word he publishes put in doubt, tested, and re-tested. Every number he writes will be measured again and again by people all over the world who will refuse to accept his word for it.

In fact, the worst that can happen to a scientist is publishing a work about which no one expresses any doubt, because this would mean it's considered irrelevant. A relentless series of whithering attacks is what keeps any *true* scientist alive. Only crooks fear being put to test.

This is a trend that I believe was started back in the day of Carl Sagan

Ah, no, it's much older than that! This trend dates at least to Isaac Newton.

That's not a star . . .

[StefanJ]

It's a very, very large gamma ray laser, created by a very patient race with an enemy living in a globular cluster whose orbit around the galaxy will take it into the path of the polar emission stream.

The other pole's stream will be redirected with a vibrating unobtanium mirror and used to paint advertising slogans in a gas cloud on the edge of the Lesser Magellanic Cloud.

Speed of causality

[Roger W Moore]

After all, the speed of light is really just the speed of causality.

No, the speed of light is the MAXIMUM "speed of causality". A causal connection between events can happen at less than the speed of light. A simple example is hearing thunder sometime after seeing the lightning strike in a thunderstorm. The connection between the two events (lightning flash and the thunder) propagates at ~330 m/s (the speed of sound in air). All relativity tells you is that the connection between two events cannot propagate FASTER than light i.e. you cannot detect any effect of the lightning before it is visible.

No. If you'd review your time travel verb tenses

[ElboRuum]

You'd see that in this case, you need to use the future past perfect subjunctive, which would be:

"The star is about to will had haven been exploding."