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Reversing Magnetic Poles Observed in Another Star
Babu 'God' Hoover tips us to news out of the University of Hawaii Institute for Astronomy that for the first time, a magnetic pole reversal has been observed in a star other than our own. Tau Bootis, while similar to the Sun, also has a planet more than six times larger than Jupiter orbiting at only a twentieth of the distance between Earth and the Sun. Scientists hope to use this discovery to learn more about the magnetic dynamics in the Sun, which can affect our telecommunications, among other things.
Actually, star names are truly a pain in the back office.
In most of the star catalogues the first field is a running number (ID). After the catalogue is published that ID number becomes yet another name for that star. Some stars have a hundred of these names.
Most stars are actually systems of multiple stars. Some catalogue numbers refer to the whole system. Some give each component a distinct ID. Some add a letter, a dot following a number, or dash, or something else.
Catalogues do have errors due wrong identifications and technical problems.
How about plain simple coordinates? No need for names, but coordinates relative to what? In space and time nothing is in rest.
More clever approach would be to use the 'stellar DNA' called spectrum. It contains the chemical composition of the star. Very unique, but again, there are wrong identifications and technical problems.
The shocking thing is that most stars do not have names.
The second shocking thing is that universal naming convention for stars is not feasible.
We humans, we small and silly, try to name everything...
Magnetic fields can affect the polarization of photons. So I suspect that there is an instrument which measures polarization, and that polarization has flipped from some previous measurement.
There is a mention of " ESPaDOnS, the new generation stellar spectropolarimeter" as being the instrument involved. Link here http://www.ast.obs-mip.fr/projets/espadons/espadons.html
Why would you bring up climate change? We've known for many years that the Sun flips its magnetic field every 11 years or so. This is simply the first time we've observed it in another star. The flipping of Sol's magnetic field causes a change in the number and size of sunspots which do affect solar output. This has been taken into account with climate models that show the earth is warming due to human influence. This news story offers absolutely no information pertinent to climate change.
Because we do not know some things does not mean we cannot know others. The fact that the theory of General Relativity does not work at atomic distances does not mean that we can't use it to determine clock skew in different gravity fields. GPS would not work without taking General Relativity into account if you want proof you can hold in your hand. Because we do not know everything about Quantum Mechanics does not mean that we cannot use the theory to create lasers, which are a direct result of quantum mechanical theory. You would not have CD and DVD drives if the theory wasn't mostly correct.
What you are basically saying is that we should throw up our hands and say that whether climate change is occurring due to human influence is unknowable. That sounds nothing like an 'INFORMED decision' as you put it. If you are truly interested, do some research yourself. I questioned man's influence on climate change also until I looked into it. Researchers who study the subject are almost completely of one mind, that humanity is influencing the climate and causing the world to be warmer that it has been in the past. These are people that spend their lives looking at all of the evidence, people that ask the questions you want the answers to and try their best to find them. The people that just throw their hands up and say that it is unknowable are the ones that deny global warming is happening. Some point to one of the warmest years on record being in the 1940s, but that is explainable due to normal cycles. Check out the trends though. Global warming is a FACT, that human influence is causing it is a theory with mountains of evidence supporting it and no evidence against it. The only other thing that people can point to as the cause for global warming is "something we don't know yet".
The way they find out is taking a spectrum of the star light. The spectrum, via prisim/spectrial grating tells us what the object is made of, its temperature, ans if an effect knowen as, for give my spelling, Zieman spiliting effect takes place on the spectrial lines, there is a magnetic field present on or applyed to the luminus object. The object can be a star, candle flame, Heated iron, basicly anything that gives off light. All you need is a light source. No great or even mediourcer resoilution necessary, just the bear minuim light.
How can we actually detect the magnetic field of another star?
I don't know about stars, but for our sun, we determine magnetic polarity by studying the polarization of the light coming from it. Magnetic fields can polarize light.
Table-ized A.I.