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Astronomers Find Unusual Star
First time accepted submitter JoshuaZ writes "Astronomers have found an unusual small star. SDSS J102915+172927 is a small faint star with very little of any elements other than hydrogen or helium. The star's composition is surprising (Pdf) since standard theories of star formation require heavier elements in small stars in order to allow the stars to be heavy enough to come together. Possibly the most unusual aspect of this star is the complete non-detection of lithium which would be expected in a star of this size. The only elements created shortly after the Big Bang were lithium, hydrogen and helium, and the star should have lithium levels much higher since they should correspond closely with the levels believed to have been formed shortly after the Big Bang."
That is unusual.
I always like to know how far away something is from us. Most articles on the web give direction toward Leo, but for distance I only found one reference that said it was hovering 3,500 light-years above the disk of the Milky Way. So it's near our Milky Way
http://www.cosmosmagazine.com/news/4690/impossible-star-discovered
Jupiter is also like 99.7% hydrogen and helium, but I guess they're assuming that the Sun gobbled up most of the heavier elements when our solar system was forming.
Many parts of the bible lend credence to your theory that He runs out of lithium from time to time.
How can I believe you when you tell me what I don't want to hear?
>>God made it that way to test your faith.
If god wanted to test our faith with impossible stuff, he could have simply made a huge mountain-sized boulder magically float in air over the vatican, defying gravity. Miracles are more appreciated when they are closer home.
He put one in Mecca, but he got tired of it and dropped it after a while...
While I agree with the contention that the simplest explanation is likely the right one
Why would you agree with something so nonsensical? And why would you state such a belief in the context of Occam's Razor, which says nothing of the kind. Occam's Razor says that, if a model works without one of its factors, then it is safe to remove that factor. It's a rule about logic, not about science. If you start with a set of axioms and develop a system, then there are an infinite number of axioms that you can add without changing the validity of any of your interred rules, but adding these does not gain you anything.
An example of its application in science is the idea of guided evolution. One model suggests that species change via random mutations. Another model suggests that these changes are not random, that they're guided by a higher power in such a way that is indistinguishable from random change. Occam does not say that the second hypothesis is wrong, merely that it adds nothing useful to the model. You could also add another factor to that saying that it's guided by a higher power who makes decisions based on what an angel tells him. You could go on adding extra layers to this hypothesis forever, without altering the predictions that are made. You can, therefore, save yourself some mental effort by ignoring the factors that are irrelevant.
That doesn't mean that the first theory is 'right', or true, it just means that it's simpler and equally useful.
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I think you mean "Contact". Contact is the Sagan scifi novel that touches on this and was made into a movie. Cosmos was the TV showed he starred in that was about astronomy.
Actually, some of us are pretty easy about it. Although the Christian God is contradictory enough to be impossible to fully demonstrate, I for one would settle for a much less powerful being as God. Or as a god.
And it's not just me. For 99% of the existence of the human species, we lived just fine with much less omnipotent gods. Even the Jewish God of the OT, actually promised a lot less. Heck, until very late, he didn't even promise an afterlife at all. (In fact, Genesis even spells it out that God _didn't_ want humans to have eternal life.) Other civilizations were perfectly OK with Gods of limited powers, or not immortal (see the Norse Gods), or even already dead (see Osiris.)
I mean, take the traditional supposed powers of a Pharaoh, as an incarnate of Horus. He was supposed to bring fertility and prosperity by just being there, bring Ma'at (justice, orders, etc) to the land, etc. And of course, be the representative of some guys who can give an afterlife.
Let's say some dude came forward and claimed that he is the new incarnate of Horus. How would we go about testing it? Well, for example, let's see if he can influence the fertility of some plots of land, in a double-blind experiment. He gets 100 randomly selected farms he has to boost the production of, 100 he must lower the production of, and 100 more are chosen as control. Repeat that for 2-3 years.
Nobody else knows which farms, until it's time to compare results.
Ma'at? Same deal. Get a list of 100 random cities where the criminality must drop faster than the nation average. Can he pull that stunt?
If he wants to go for even more god points, let's see, Rameses II at Kadesh claimed to have been at some point deserted by all his soldiers and that he personally, with his divine dad Ra as help, repelled the assault of the Hittite chariots at the crucial point of that battle. So it seems to me like there is precedent that the incarnate Horus could use his superhuman powers in battle. Well, we can test that too. We set the guy against a few remote controlled drones or vehicles with belt-fed beanbag ammo, and he must destroy some of them without getting beaned.
If someone can do that, personally I'll cheerfully proclaim him a god. Maybe not THE God, and I may have my doubts about whether it's actually supernatural (as opposed to, you know, it being natural that someone is a god like that;)) but I'll cheerfully grant that guy a minor god status. I might even volunteer to pull rocks for his pyramid, because, hey, it can't hurt to get on a god's good side.
A polar bear is a cartesian bear after a coordinate transform.
Jesus.
1) People calling something "dark" doesn't mean they literally believe that, for instance, "dark energy" exists. What they know is that observations cannot be accounted for without something that acts the way "dark energy" acts, in the equations they currently employ. There is enormous research in this field pursuing a wide range of approaches to reproducing the observations theoretically. The simplest models employ a "dark energy" -- literally, something that does not interact with light, and which has a pressure sufficiently negative as to accelerate the expansion of the universe. No-one -- and I mean NO-ONE -- who works in the field treats these as anything other than toy models. Phenomenology, to use the jargon. More complex models attempt to see what changes to the assumed laws of gravity are necessary to reproduce the effect. No-one who does this pretends that their model is anything other than a toy model. (Indeed, most modifications to gravity can be rephrased as a dark energy of the first kind anyway, albeit a really weird, ugly one. It's the motivation that's different.) More controversial models attempt to reproduce the observations by changing one of the fundamental assumptions that lead to the standard cosmological model: homogeneity. Violate homogeneity and you can influence the paths of photons around us in ways that mimic "dark energy". No-one working on this pretends that it's anything other than a toy model. Yet another approach is to point out that the universe is intrinsically inhomogeneous and anisotropic and attempt to reconstruct the homogeneous universe we employ in cosmology from that. No-one working on this pretends that the models studied so far are anything other than toy models.
It's not "scientists" "making up" "dark" "somethings" that can be "plugged into equations" but "never detected", it's people tagging a puzzling observation with a placeholder ("dark energy" for the anomalous acceleration of the universe; "dark matter" for the apparent necessity across a massive range of scales for large amounts of clustering matter that doesn't interact with light) and then exploring potential explanations.
I don't care if you were trying to joke. This kind of accusation really annoys me because it suggests that either we're terrible at explaining what's going on, or people simply aren't listening to us;, or both and people who argue this way tend to insinuate that those of us in astrophysics are a pack of idiots or charlatans fraudulently inventing arbitrary and unobservable physics in order to screw millions upon millions of euro from the honest taxpayer. And that's frankly offensive.
>It's considerably more likely that our theory(/ies) of star formation are lacking.
It's even MORE likely that our theories are generally correct but some specific unknown circumstance caused this particular star to follow a different and unexpected path. This star is not matching the previously observed observations on which our theories are based. The most likely explanation is that something highly unusual (perhaps entirely unique) happened here - we don't yet know what, something that cause it not to do what usually happens.
This is not so much a shortcoming of theory then - theories are generalized models of how the universe behaves which are true most of the time, when all the variables are the same. What we see here is a very clear case that one of those variables must have been very different. We don't yet know why. Finding out why is a challenge and worthy one. It could disprove the theory (one failed experiment does - but only if the variables are the SAME) - more likely we'll end up amending the theories to also include the particular type of star formation that caused this.
That doesn't make the theory false for all the other stars - it could, it could be that we were wrong all along, - but that is doubtful we've got lots of observations of stars of various ages that follow the predicted paths of the theory, this exception should therefore raise an expectation of something unique happening differently.
An object falling should accelerate at 9.2 m/s2 - that's a valid scientific theory. If there's air resistence it won't reach that though, and depending on how much the impact will vary - a more refined theory talks of terminal velocities in earth atmosphere (and those aren't perfect since air density is not a constant). Throw in a parachute and your prediction of how fast something will fall is now way off.
That's not because the theory of gravity is wrong, it's because the parachute is an unlikely additional factor that doesn't usually enter ito the equation - but we can write a theory of how parachutes will change the prediction (once observed) and deal with that situation seperately.
So the smart money is that we'll see a new theory to explain how some small stars can exist without heavier elements, which doesn't replace the usual heavy elements are needed in small stars theory, it just adds an "unless" clause.
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Why? The quantities of heavy atoms made in the original big bang nucleosynthesis are widely accepted to have been miniscule. Non-trivial quantities of elements heavier than beryllium didn't exist until stellar nucleosynthesis started. And beryllium itself was produced in such hilariously tiny amounts that it's usually forgotten.
No kidding!!! What do you say at this point?
If so, then it could be the exhaust plume of a Bussard Ramjet.
Oops! Sorry! Wrong reality...
I'm not an anstronomer either, but the article summary did specifically say small star. The wikipedia article on red dwarfs mentions that as of 2009 there is a 'mystery' as to the absence of red dwarfs with no metals, and the preferred explanation is that without metals only large stars can form. So that theory allows for the bigger stars forming, creating heavier elements, and then exploding, spewing those elements out into the universe. Even if red dwarfs had been created at the beginning, they are so long lived they would not have exploded and released heavier elements into the rest of the universe yet anyway.
In theory, theory and practice are the same; in practice they're different. (Yogi Berra & A. Einstein)