sbobet888 ดีไหม_คาสิโนลาว เชียงแสน_casino ฟรี เครดิต Evilness science feed. en-gb /d4d/layout/professional/images/icons/syndication.png Evilness - science How we know there&#039;s no counter-Earth hiding behind the Sun. <p>For centuries there has been speculation about another planet on the same orbit as the Earth, but hiding behind the Sun. Sometimes this is used as a plot device in science fiction or by some conspiracy theorist to explain something. The reality is we know there isn't a planet hiding behind the Sun and here's why:</p> <p>First off we'd see it. I don't mean in telescopes, but it would be an unaided eye object. The reason why is quite simple and has to do with orbital mechanics. Now for an object to remain hidden behind the Sun it would have to be moving the same speed the Earth does in it's orbit. Which would work if the Earth orbited the Sun in a circle. It doesn't. Planets orbit according to <a href="">Kepler's Laws of Planetary Motion</a> the first of which is that the planets orbit the Sun in ellipses. Now the Earth's orbit is nearly circular but is elliptical enough that the difference between our closest approach to the Sun and our furthest (perihelion and aphelion) is about 5 million kilometres. </p> <p>Kepler's second law basically states that the closest a planet is to the Sun, the faster it moves and the further it is from the Sun the slower it moves. So the Earth is constantly speeding up and slowing down in its trip around the Sun. A counter Earth would have to do the same. Now since the counter Earth would be opposite the Sun from the Earth, it would be at perihelion when the Earth is at aphelion and vice versa. Some quick calculations here at Castle Evil show that the difference in orbital velocity for the Earth between perihelion and aphelion is about 1 km/s (0.995 km/s for the pedants out there). This means that at part of the orbit our counter-Earth twin would be racing to catch up with us at 1km/s and then running away from us at the same speed 6 months later. Now to be visible the counter-Earth would have to be out from behind the solar disk. At 1 km/s it would take about a month for such a body to be one solar diameter away from the solar disk at perihelion/aphelion. This means that for all practical purposes a counter-Earth would only be actually hidden from us for a few months a year as it appeared to swing from side to side behind the Sun.</p> <p>Since such a body would only be hidden for few months or so and would clearly be visible to the naked eye (Mars is smaller in diameter and is visible when it is farther away than a counter-Earth) most of the time. So from this alone it is safe to say there is no planet in the same orbit as the Earth hiding behind the Sun.</p> <p>Even if a counter-Earth were able to stay behind the Sun for some reason, we'd still see it's effect on the orbits of other planets. As the planet Venus, for example, lapped a twin Earth, the twin's gravity would tug at Venus causing measurable perturbations in Venus' orbit. Since no such perturbations have ever been observed, it is further evidence that there just isn't a planet hiding behind the Sun.</p> <p>So the lack of a visible counter-Earth and no perturbations in Venus' orbit are evidence that it's not there, but further against the idea is that it's dynamically impossible. The counter Sun point is one of five <a href="">Lagrange points</a> that exist as part of the Sun-Earth system. Of the five Lagrange points, L4 and L5 are stable. They are analogous to a valley where if you put something there it takes a fair bit of energy to dislodge it from the point so no station keeping is needed. L1, L2 and L3 on the other hand are saddle points. This is analogous to being on a ridge. Though something can stay on the ridge it doesn't take much to push it off the ridge and down the slope below. As such any object at the L1, L2 or L3 points is unstable and requires some form of station keeping to maintain it's position. The counter-Sun point is L3. This means that any planet at L3 will have problems staying there, as the gravitational perturbations of the other planets (Jupiter for instance) will tend to push an L3 planet off the point and into a different orbit. Thus not only would we see a counter-Earth, it wouldn't stay at that point for very long before it was pushed off the L3 point into a completely different orbit. Which would obviously make such a planet visible.</p> <p>Of course our Earth would be in the counter-Earth's L3 point as well, making the Earth's orbit unstable for the same reasons. Since the Earth is in a stable orbit, nothing the size of the Earth is hanging out at our L3 point.</p> <p>So the notion of another planet sharing our orbit about the Sun but hidden behind the Sun is an interesting idea and fodder for questionable science fiction (and even more questionable conspiracy theories) however there is nothing there. At the end of the day it's a dynamic impossibility and even if it were possible we'd see it and it's effects on the other planets in our solar system.</p> Tue, 03 Nov 2015 12:17:09 -0700 What I do in science <p>Occasionally I get asked as to what I actually research in astronomy so I thought I'd create a post that explains what my current research project is about. First some generalities: my interests in astronomy are related to stellar evolution and galaxy interactions (these topics are generally unrelated, though galaxy mergers do set off a storm of star formation in disk (spiral) galaxies). Specifically I find how stars end their lives quite fascinating. Supernovae, black holes, pulsars/neutron stars, planetary nebulae and white dwarfs are all majorly cool in my world. </p> <p>At this point in time I am studying planetary nebulae (PNe in plural, PN in singular). Planetary nebulae are a phase of stellar evolution where stars less than eight times the mass of the Sun (including the Sun) have blown off their outer atmospheres leaving behind the glowing core. The core has stopped undergoing fusion but is still millions of degrees in temperature. The outer atmosphere has been blown far into space by stellar winds and now the ultra-violet light being produced by the hot core remnant (often called the central star) causes this gas to glow. We see this gas as the planetary nebula. As such this is the penultimate stage in the death of Sun like stars, the final stage being a white dwarf.</p> <p>That these nebulae are called planetary is a quirk of history as they have nothing to do with planets. When these objects were first discovered in the late 19th century they appeared though the telescopes of the day to look like the planets Uranus and Neptune but spectroscopy of them showed they were nebulae. Thus the moniker planetary nebula (some contemporary astronomers have suggested renaming them, but if you thought there was an uproar over Pluto?</p> <p>So now you have a general idea what a planetary nebula is. Now as we see them in the sky PNe seem to come in two broad categories, round(ish) and bi-polar.<br /> [image1] [image2]<br /> <em>Image 1 and 2: An elliptical (round) PN (IC418) and bipolar PN (M76)</em><br /> There are of course many different types within these two broad categories, but for the sake of this discussion the two broad categories will do. It is also clear that many apparently round PNe are simply bipolar PNe seen edge on.</p> <p>Now we are still uncertain with what causes PNe to be bi-polar. There are three current hypotheses, which are not mutually exclusive in that it is possible for each one to be a cause of the collimation that forms the lobes of the bi-polar PNe. First up is that there is a disk of dust and gas around the dying star and this forces the gas leaving the star into the two lobes of the bipolare PNe. Second is that there is some unseen companion in orbit around the dying star and gravitational forces cause the collimation. Finally the dying star has a strong magnetic field and this causes the two lobes.</p> <p>Now there's nothing that says that these couldn't all be the cause around different stars and the evidence for them is mixed. Some proto-planetary nebulae have been spotted with disks of material around them. Some PNe have evidence of an unseen companion. The only hypothesis of the three that is quite weak is the magnetic field hypothesis; as most stars the mass of the Sun don't generate a strong enough magnetic field so would have to be somehow "spun up" to rotate faster to generate one.</p> <p>This is where I come in. It has been argued that all PNe are bipolar and that the round ones are just projection effects. That being said there is some evidence that some of the round ones are actually round. Not only that, but the ones that are round come from lower mass progenitor stars (a progenitor is just the thing that came before what we're looking at now). Both Henry et al (2010) and Manchando et al (2000) suggest that the round/elliptical PNe come from lower mass progenitors and that the bipolar stars are made up of more massive ones. What I am doing is looking at a sample of planetary nebulae of various morphologies (shapes) and determining what the initial mass of the progenitor star was likely to be. From this it can be seen if this lower mass makes round PNe hypothesis is likely to be correct.</p> <p>The problem is "weighing" the progenitor. Normally we can <a href="">determine the mass of an object</a> by watching how some other object orbits it. We can also see how a really massive object bends light around it and determine its mass that way. Neither of these methods can be used with planetary nebulae for three reasons. First there is generally nothing detectible orbiting the PNe; second they are not massive enough to measure the light bending around them; and third and most importantly the progenitor star has loosed its non-core layers into the universe so isn't there to be weighed at all. This means some other method must be used.</p> <p>How I determine the mass of the progenitors is indirect and provides a relative indication (not absolute) of the progenitor mass, but this will work for the purposes of testing the hypothesis. The method works based on the following:</p> <p>First compared to the lives of the stars that form them, PNe are quite ephemeral things, lasting only several tens of thousands of years (this is a very short period of time in astronomy). This means that the PNe that we can observe are in essence more or less formed at the same time (compared to stars). This allows the next steps in the line of reasoning.</p> <p>Though the PNe themselves are more or less the same age, the same can't be said of the progenitor stars. There is quite a range of ages based on the initial mass of the progenitor. For example stars of around the mass of the Sun live on the order of about 10 billion years. Stars only 5 times greater than that, 5 solar mass stars, live only about 1 billion years. This means that though both of these stars produce PNe, for the PNe we see today some of the stars were formed 10 billion years ago, some only 1 billion or so years ago.</p> <p>This range of formation times is important is that as time moves forward, our Galaxy becomes enriched with more and more elements heavier than hydrogen and helium. This is because in that time frame stars born much earlier die and throw the elements made inside them into the Galaxy to be made into new stars. Thus we would expect stars born earlier in time (longer ago) to have less of these heavier elements than stars born later in time (less long ago). So if a PNe has more sulphur than another, its progenitor must have been formed later since in order to gain sulphur it would have had to be born in a later time where more sulphur was available.</p> <p>I used sulphur in the previous example purposely. Sulphur is made in stars, but not those that form PNe. Much more massive stars are needed to make sulphur so we know that the amount of sulphur in the star, and hence its PNe, is from when it formed and not because the star made it. So if the amount of sulphur in a PNe can be measured, it provides a marker for the size of the progenitor star. More sulphur means the progenitor star was heavier. Thus a graph of sulphur abundance is also a graph of progenitor mass, even if we can't tell exactly how much mass the progenitor had, we can still tell if one was more likely to be heavier than another.</p> <p>Now the trick is to measure the sulphur abundance of the PNe. This is doable! There's a couple of ways this can be done. First and more traditionally a <a href="">spectrum</a> would be taken, the sulphur lines located and measured and compared to some other line (in astronomy abundances are always given as a ratio of one element to another as this counteracts effects due to changes in brightness due to factors other than the amount of the element present). To do this requires a spectrograph and they aren't cheap. So I use the second method, which is a form of photoelectric photometry. I use a CCD imager that uses a monochrome CCD chip similar to the colour chips used in your camera phone to take images of target PNe through various filters. One of these filters only sees the light from an <a href="">emission line</a> of hydrogen known as <a href="">hydrogen alpha</a>. Another filter allows the imager to only see the light of a certain emission line of sulphur (known as <a href="">sulphur[II]</a>). By comparing the brightness of these two lines as seen by the imager one can infer the abundance ratio of sulphur to hydrogen and hence the relative mass of the progenitor.<br /> [image3][image4]<br /> <em>PN NGC 2371 in H-alpha (left) and S[II] (right) light</em> </p> <p>So that, in a nutshell, is the general focus of my research. Feel free to contact me to ask questions!</p> <p><b>References:</b></p> <p>Henry, R.B.C., Kwitter, K.B., Jaskot, A.E., Balick, B., Morrison, M.A., Milingo, J.B., 2010, ApJ 724, 748</p> <p>Manchado, A., Villaver, E., Stanghellini, L., &amp; Guerrero, M. A. 2000, in ASP Conf. Ser. 199, Asymmetrical Planetary Nebulae II, Kastner, J.H., Soker, N. Rappaport, S. eds (San Francisco: ASP), 17</p> Thu, 20 Aug 2015 19:40:19 -0600 Asteroids: why we should look for them and how we do it. <p>In the past few years the astronomical community has begun to expend a fair bit of resources in the search for asteroids. Apart from the curiosity aspect of looking for such objects, there is a real, practical reason to locate these things: an asteroid collision with the Earth.</p> <p>The collision of the Earth with an asteroid has the very real possibility of causing an <a href="">extinction event</a> such as <a href="">happened to the dinosaurs about 65 million years ago</a>. Only this time it won't be the dinosaurs that will be wiped out, it will be us. This is the practical impetus in looking for asteroids, especially a class of asteroids known as <a href="">Near Earth Objects (NEOs)</a> as these are the ones with a possibility of hitting the Earth.</p> <p>Now as of this writing there are <a href="">about 12800 <em>known</em> NEOs</a> of all sizes. Of these there are <a href="">about 1600 <em>known</em> Potentially Hazardous Asteroids (PHAs)</a>. I've emphasised the word "known" for a reason. We discover several hundred NEO's a year (of which about 13% will be PHAs). The PHAs are, upon discovery, the asteroids that get intensely studied, as we need accurate orbit determinations to work out if they will impact the Earth. It is important to note that an asteroid being a PHA does not automatically mean it will impact the Earth, but that the potential is there and we should keep our eyes on it.</p> <p>So that is the why, now for the how. Asteroids are very dim. This is due to the fact that they are a) small and b) have low <a href="">albedos</a>. Compounding this is that they tend to look just like dim stars on an image plate such as this:</p> <p>[image1]<br /> The asteroid 2-Pallas is in this frame</p> <p>Now I won't blame you if you can't find the asteroid <a href="">2-Pallas</a> on this frame. So the trick is to find the asteroid. We do this by taking an image of the same part of the sky at a different time. The stars are so far away that in any reasonable period of time (a few days for example) the stars will not appear to move, but the asteroid will. This GIF animation shows Pallas' motion over the period of an hour:</p> <p>[image2]<br /> Pallas' motion over an hour</p> <p>A pretty way is to take three images over a period of time and make a colour RGB image, each image forms one of the red, green, or blue channels. In this case the stars come out as basically white and three dots, one red, one green, and one blue mark where the asteroid has moved:</p> <p>[image3]<br /> Three colour asteroid image.</p> <p>Seems simple enough, except that it's a big sky. The image of Pallas is from a moderately sized telescope (0.2m) using a relatively small imager. The frame is about 0.64 degrees of arc by about 0.48 degrees of arc or about 0.31 square degrees. The entire sky is about 41253 square degrees so this image is about 0.0007% of the sky. A search with this instrument would be a time consuming task indeed.</p> <p>Using an instrument with a larger field of view will help with that, but causes a second problem, there are a lot more stars in larger fields of view. Now it will take more time after the observation to check to see which points of light moved. One way is to use two images (like those used to make the animation above) and use a computer to mark where each star is on each frame and show the ones that moved. There will be false positives of course, which will have to be followed up by human intervention. One can also subtract one frame from the other (earlier-later) which gives something like this for our frames of Pallas:</p> <p>[image4]<br /> Pallus with the stars subtracted.</p> <p>In this case the fixed stars should subtract out leaving just the asteroid. Though if you look closely there are some false positives here too due to imaging factors.</p> <p>So the difficult task remains, but an important one. There are many <a href="">projects seeking these objects</a> and it is an area where amateur astronomers looking for a project can do some real science by joining the hunt. I won't go into what to do if we find the asteroid with our name on it, that's for another post on another day.</p> Sat, 01 Aug 2015 15:19:36 -0600 Food Babe Vani Hari ?Scientifically Ignorant or Con Artist? <p>A few months ago I became aware of a blogger known as Food Babe. This is the nom de plume of one Vani Hari, a self-styled "food activist". Now the way I came to know of her is through an article she wrote for her followers on the "dangers" of air travel (more on this later). After some further research it is apparent that Hari is either very ignorant of science or is a con artist who's able to parley fear into having people hand money over to her for her "advice".</p> <p>To begin who is Hari? Well her previous profession prior to becoming a blogger was of a <a href="">banking consultant with formal training in computer science</a>. At this point it is important to note that she has no training in chemistry or nutrition. One could argue that she was self taught at Google U., but the following example will show that she failed even that:</p> <p>At one point, either through sheer ignorance or in an attempt to instil fear in her followers, <a href="">Hari claims that propylene glycol is found in beer.</a> In a <a href="">broken clock</a> moment she correctly identifies propylene glycol as a form of antifreeze. What she fails to point out is that it is used as a non-toxic alternative to the more toxic ethylene glycol and that propylene glycol, like water, is only toxic in large amounts. The anti-freeze argument is bogus since brine (salt water) is also used as an anti-freeze and salt is essential to life. It's a pure scare tactic with no basis in science used on the hope that her readers are as ignorant about chemistry as she seems to be (or plays at being)</p> <p>Well apparently someone pointed out that propylene glycol in the brewing industry is used as a coolant (presumably since it has very low toxicity leaks are less of a concern). So she then basically goes <a href=""><em>oh I meant propylene glycol alginate<em></em></em></a> presumably because she thinks (or at the least hope her readers think) that since the chemical contains the term "propylene glycol" that it's the same thing. Except it isn't. Propylene glycol alginate is an ester of alginic acid which is extracted from kelp. That's right it's an all natural and organic ingredient. Further propylene glycol has the chemical formula C<sub>3</sub>H<sub>8</sub>O<sub>2</sub> whereas propylene glycol alginate has the chemical formula C<sub>9</sub>H<sub>14</sub>O<sub>7</sub>. To say they are the same thing is to say that water (H<sub>2</sub>2O<sub>2</sub>).</p> <p> [image1]<br /> <em>(Hey Foodbabe Army, better get on this dangerous chemical)</em></p> <p>So what we have here is an example of either how little Hari knows of even <em>basic high school</em> chemistry or that the hopes that the rubes that follow her and provide her with money have no understanding of chemistry. </p> <p>Now one could say it was a one off but it seems to permeate her entire site. Blogs by actual scientists such as <a href="">Joe Schwartz of McGill</a> have taken her to task on her many errors that if she had actually done any research she wouldn't have made.</p> <p>Further adding to this her "don't eat any chemical you can't pronounce" mantra is utter folly. For example lets look at a banana:<br /> <a href="">[image2]</a><br /> <em>Click on image for full size PDF</em><br /> Lots of chemicals in there, most of which are pretty hard to pronounce, let alone know what they are. Some of them in large enough doses are lethal in humans. Should you not eat bananas? According to Hari the answer is no since it contains nasty chemicals.</p> <p>Now not only does she not have a firm grasp on chemistry but she's posted some doozies in the past that she's tried to disappear from the internet (one would think that someone with a degree in computer science knows that once you post something to the internet, it's there forever). First is <a href="">her article on flying</a> which is so rife with inaccuracies that when I use it in a class on critical thinking I have students (gr 9-10) laughing at it <em>before I even go over what's wrong with the article</em>. Think about that for a moment ?14 and 15 year old kids figure out that she's full of crap whereas her "army" has yet too. Looking at this article we can add that Hari also doesn't know a) the composition of the Earth's atmosphere and b) how airplanes work. To be fair she has a couple of stopped clock moments in the article, but the vast majority of it is hopelessly wrong.</p> <p>Then there's her <a href="">microwave oven article</a> (also disappeared) which can only be described as bovine scatology that a simple Google search would have prevented. I can only think that she just made the whole thing up, either because she is so ignorant of physics and chemistry that she believes it, or like the spelling errors in a scam letter, she posted it to clear her followers of anyone capable of critical thought.</p> <p>So Hari presents large swaths of information that are demonstrably wrong. When she makes errors she either doubles down, ignores them or tries to disappear them. So at the very least she's intellectually dishonest. But at this point is she simply a woefully misinformed do-gooder or an actual scam artist?</p> <p>Well lets look at what we have so far: Hari presents wrong information. When the information is so wrong even a child can see through it, instead of saying that the information was wrong and correcting it, she disappears it. When people with actual training in the fields of chemistry and nutrition point out the other information as wrong, instead of going "whoops" and correcting the problem, she attacks the messenger as well as claiming she was "misinterpreted". These are not the hallmarks of a misinformed do-gooder, but of someone who's livelihood is dependent on a continual stream of marks coming to her website to buy stuff (some of which <a href="">containg the very same chemicals she says not to use</a> or <a href="">as much sugar as many beverages she pans</a>) trying to protect her reputation as "knowledgeable".</p> <p>This has her leaning into con artist territory. She tells you not to eat certain things, but then makes money off of selling you things that contain the very same things. When her errors are pointed out, instead of correcting them she either disappears them or accuses those of pointing out her errors as being part of some big food conspiracy against her and her followers. Her actions are ones of someone who is creating a brand of herself for her own personal gain and defending that brand just like the food companies she bashes.</p> <p>So is Hari scientifically illiterate or a con artist? The scientific illiteracy is demonstrable, though could be an act. The fact she sells many of the "chemicals" that she opposes suggests she either doesn't check her labels as well as she tells everyone else to or knows that the stuff is there but would rather make a fast buck than be honest with her <del>marks</del> fans.</p> <p>Some links to some other criticism of Hari:<br /> <a href="">And they say I'm in it for the money?</a><br /> <a href="">The Food Babe Hath Spoken, And Subway Bread Will Still Suck</a><br /> <a href="">Is The Food Babe A Fearmonger? Scientists Are Speaking Out: The Salt: NPR</a><br /> <a href="">Food Babe Vistis My University</a><br /> <a href="">Scam Stud</a> (My favourite quote out of this one:<em> I admire the way Food Babe can take a complex and nuanced topic and distill it down to an aliquot of pure error. It is a talent rarely seen outside of the Tea Party. </em><br /> <a href="">Making One's Own Reality ?Food Babe Edtion</a><br /> </p> <p>These are just a small number of criticisms of Hari, most by actual scientists and physicians. The fact that Hari can gain such a following is truly an indictment on the state of science education in North America.</p> Sun, 03 May 2015 00:55:40 -0600 The wonder of science. <p>I often use this <a href=""> Brian Cox video</a> to show that yes, objects of different masses fall at different rates. This is in of itself a cool thing to watch and worth looking at the video for. As an aside, Apollo 15 did the same experiment with less explanation but being way higher on the coolness factor because they did the experiment <em><a href="">on the Moon!</a></em></p> <p>Now the video clip is cool just for what it is showing but for me the even cooler bit comes at the point where they show the reaction of the control room staff. Apart from Brian Cox, who is a PhD physicist, the room is filled with the people who operate the facility. These people will be scientists and engineers of some sort. In other words everyone in the control room <em>knows what is going to happen</em> when the bowling ball and feather are dropped in the vacuum chamber.</p> <p>Which is why I find their reactions cool. It's a combination of awe and delight. A reaction you wouldn't expect from a bunch of people who pretty much know what's going to happen. This speaks to me of why people end up in the sciences. This sense of wonder about the world we have as children doesn't go away for scientists. Even seeing things that we know will happen work hits the wonder button in us.</p> <p>In the end the world is an amazing place in both the small things and the grand scope. The key is to ensure that everyone retains the sense of wonder. That will go a long way to increase the scientific literacy of our population, something that is sorely needed.</p> Mon, 20 Apr 2015 19:53:37 -0600 Contrarians <p>We all know someone that would be considered a contrarian, someone who goes against the norms of oneís social or work circle or society in general. Normally these people are seen as quirky at best or cantankerous curmudgeons at worst. There is nothing wrong with them, unless their contrarianism swings into the criminal, so why am I writing about them? Well in the field of science there are also contrarians. Again this is usually not an issue as they often provide a devils advocate for ideas and force the mainstream theories to be viewed with the scepticism that all ideas in science need to be seen with. That being said their existence is a problem for the public as one can usually find a contrarian scientist to ďprove?whatever pseudo-scientific claptrap one can come up with causing the proponent of the claptrap to claim that the ďscience isnít settled?</p> <p>To illustrate this I will use an example from cosmology (as an astronomer it is an example that Iím most familiar with). Prior to the 1920ís astronomy was uncertain as to the scale of the universe. There was even a <a href="">Great Debate</a> between two preeminent astronomers of the day (Harlow Shapley and Herber Curtis) about if there were galaxies outside our own. In the mid 1920ís another astronomer, Edwin Hubble (yes THAT Hubble), measured the distance to what was then known as the Andromeda Nebula. Turns out the Andromeda Nebula was over 2 million light years away and could not be in our galaxy. Thus it came to be understood that the universe was likely infinite. </p> <p>As a side note, Shapley, who was a proponent of the spiral nebulae like Andromeda just being part of our own galaxy, changed his views once the data was in from Edwin Hubble (reportedly saying when he received Hubbleís letter "Here is the letter that destroyed my universe" . This is the essence of what a good scientist needs to do.</p> <p>On with our story. At this point the primary idea of how the universe came to be is that it was pretty much always there. This theory came to be known as the "Steady State Theory". Under this theory the universe was infinite in all directions. An infinite number of stars in an infinite number of galaxies floated through this infinite space. As stars died, new ones would be formed from the ashes, ad infinitum. This was a perfectly reasonable theory given the data of the time. The problem came in the 1930's when Hubble (it's hard to understate Hubble's contribution to cosmology) discovered that the universe was expanding.</p> <p>If the universe was expanding it would logically follow that if you ran the clock backwards, all the matter in the universe would have all massed together at some point in the past. So in other words, it was possible the universe was expanding into infinity from some point in the past when a colossal explosion sent all the matter in the universe flying apart. This provided an alternative theory to the Steady State. This theory would eventually be called the Big Bang, not by those who proposed it, but by a proponent of the Steady State theory, astronomer Fred Hoyle, who used it as a pejorative for the expanding universe theory.</p> <p>So the debate raged over which theory was correct. The nail was driven in the Steady State theory's coffin when the Cosmic Microwave Background (CMB) was discovered in 1964. The expanding universe theory (now officially called the Standard Cosmological Model) could explain the CMB and expansion while the Steady State theory could not.</p> <p>Which brings us to our contrarian. Fred Hoyle would not accept the Big Bang. He clung on to the Steady State theory till his death in 2001. He published papers on the topic well into the late 1990s and in Tier 1 journals. He and a small group of 4 or 5 other astronomers (many of who still publish on the topic) kept hammering away at the Big Bang and pushing some variation of Steady State. However the preponderance of evidence was and still is against them and for the Big Bang.</p> <p>To my point. To the astronomical community the debate was settled back in the 1960s. One could argue for most people this is also true. That being said, if I were to want to argue against the Big Bang I could point to Hoyle and his colleagues and say "Ha! See the science isn't settled!". I'd be wrong of course, but to the laity who have no background knowledge of the whole debate, I could be just as correct. At this point the layperson would have to either a) do a heck of a lot of research as to the current state of the science of cosmology or b) use their gut instinct and previous knowledge and prejudices to sort it out. Since most people don't have the time or possibly the background knowledge to do a, they'll go with b. This means that those who don't think the Big Bang is the way it happened will glom on to me and my pointing to Hoyle at the least as showing the science isn't settled and more likely to confirm their current point of view.</p> <p>To be fair to Fred Hoyle at this point much of what we know about element nucleosynthesis in stars is based on his work. It just shows that brilliance in one area doesn't necessarily translate in to brilliance in another.</p> <p>Now my main point here is that one has to be careful when one starts to buck the mainstream of science. It is possible to find contrarians in all fields of science and these are often used to sow fear, uncertainty and doubt by many on what for the majority of scientists in that field is settled science. Anti-vaxers, creationists, climate change deniers all are guilty of this, often so they can push their particular political agenda. This doesn't necessarily mean they are doing what they are doing out of malice (though that is always a possibility) but mostly from a position of ignorance. Ignorance of how science works and ignorance of their own confirmation bias when selecting sources. </p> <p>So how to determine if someone is a contrarian. First you need to determine if the field they are working in is well established or new. In my example during the 1950's A Steady State supporter would not have been a contrarian as at the time the science had not actually been settled. On the other hand if there are decades of research showing the contrarian to be out of step with the rest of his field, then the likelihood he's a contrarian increases considerably.</p> <p>Another way is to check what journals the contrarian publishes in. Not always a good indicator as Fred Hoyle shows since he published in Tier 1 journals, but if the contrarian is publishing in bottom rung journals or journals of questionable review, then one must look with suspicion their ideas. If Fred Hoyle can get a contrarian idea published in prestigious journals, there's nothing stopping others from doing so. Unless their idea is so out of step with the mainstream of science, or their methods are so shoddy that mainstream journals won't touch them.</p> <p>If the contrarian is published in a reputable journal, what are the follow up publications, both his and others? Generally if a contrarian publishes something way out there, other scientists pointing out the problems will counter it. This is apparent in the whole Andrew Wakefield vaccine/autism paper (which was eventually withdrawn). Though the paper was withdrawn due to the fact that the methods used by Wakefield would charitably be called shoddy and uncharitably called fraudulent, many other scientists hit the labs and countered with volumes of data that showed that Wakefield was flat-out wrong. This of course doesn't stop his supporters with cries of "conspiracy" and "cover up" (another sign the person is a contrarian by the way).</p> <p>Finally when in doubt use Carl Sagan's <a href="">Baloney Detection kit</a> the original of which is found in his book <em>The Demon Haunted World</em>. So my advice to you if science isn't your business is to thoroughly check out claims that go counter to the mainstream of scientific thought. Contrarians aren't necessarily wrong, but they are often not right.</p> Sat, 07 Feb 2015 17:32:09 -0700 The Windows Saga Continues <p>So the continuing tribulations of getting my imager to work with our tablet. </p> <p>So the tablet has now reverted itself back to Windows 8. The process to use the astroimager is now:</p> <p> </p><ol> <li>Find USB keyboard to hook up to tablet (Bluetooth isnít enabled at start-up)</li> <li>Turn on tablet</li> <li>Go to Change PC Settings</li> <li>Click on general</li> <li>Scroll down to the bottom of the screen and click on advanced boot</li> <li>After reboot click on troubleshooting</li> <li>Select startup settings.</li> <li>another restart</li> <li>press 7 to disable driver signature checking</li> <li>wait for machine to finish booting</li> <li>sign in</li> <li>detach keyboard</li> <li>attach astroimager, wait for machine to reinstall driver</li> </ol> <p>At this point you can actually use the imager. If for any reason the machine turns off, youíll have to go through the process again. From this I can conclude the engineers at Microsoft a)never have to do anything in the field and b) are morons. As far as I can tell Windows is the only operating system that, when a USB device is removed, assumes youíre never going to use it again and uninstalls the driver. What a load of manure. As it stands I now have to lug a physical keyboard into the field (defeating the purpose of a tablet) and plan at least an additional 30-40 minutes of set up just because Microsoft has no clue.</p> Wed, 28 Jan 2015 16:36:06 -0700 When Windows makes Linux look easy... <p>Easy minimum 28 step ?two hour process to install an astroimager driver on @Windows 8.1? </p> <p> </p><ol> <li>Attach device and wait for Windows to not find driver.</li> <li>Tell Windows where to find the driver.</li> <li>Wait for Windows to complain the driver is unsigned</li> <li>Open sidebar and click on Change PC Settings</li> <li>Navigate through menus to find Advanced Startup</li> <li>When machine restarts select Troubleshoot</li> <li>Select Advanced Options</li> <li>Select Startup Settings</li> <li>Click Restart</li> <li>Scramble around for physical keyboard to connect to tablet</li> <li>Connect keyboard and press 7</li> <li>Attach device and wait for Windows to not find driver</li> <li>Tell Windows where driver is</li> <li>Windows installs driver.</li> <li>Device works!</li> <li>Install Windows update ?Windows forgets about driver</li> <li>Attach device and wait for Windows to not find driver.</li> <li>Tell Windows where to find the driver.</li> <li>Wait for Windows to complain the driver is unsigned</li> <li>Open sidebar and click on Change PC Settings</li> <li>Navigate through menus to find Advanced Startup</li> <li>When machine restarts select Troubleshoot</li> <li>Select Advanced Options</li> <li>Select Startup Settings</li> <li>Click Restart</li> <li>Scramble around for physical keyboard to connect to tablet</li> <li>Connect keyboard and press 7</li> <li>Wait at least 2 hours for the tablet to reboot?lt;/li> Thereís no need for this insane process. I canít fathom why the rocket scientists at Microsoft would force users through it. When Linux has an easier device driver installation, you know Windows has a problem. </ol> Sun, 25 Jan 2015 21:11:09 -0700 Science - why we do it <p>Why do we do science? By this question I don't mean why does humanity do science, but why do individuals such as myself who call ourselves scientists do science? Generally we all mumble something about curiosity and wanting to know about the natural world, but as always Carl Sagan puts it much more eloquently that most of us. The following is from chapter 19 of Sagan's <em>Demon Haunted World</em> and gives the essence of why most scientists do what we do:</p> <em> Whenever I think about any of these discoveries, I feel a tingle of exhilaration. My heart races. I canít help it. Science is an astonishment and a delight. Every time a spacecraft flies by a new world, I find myself amazed. Planetary scientists ask themselves: ďoh, is that the way it is? Why didnít we think of that??But nature is always more subtle, more intricate, more elegant than what we are able to imagine. Given our manifest human limitations, what is surprising is that when have ben able to penetrate so far into the secrets of nature.<br /> Nearly every scientist has experienced, in a moment of discovery or sudden understanding, a reverential astonishment. Science-pure science, science not for any practical application but for its own sake-is a deeply emotional matter for those who practice it, as well as for those nonscientists who every now and then dip in to see whatís been discovered lately.<br /> And, as in a detective story, itía a joy to frame key questions, to work through alternative explanations, and maybe even to advance the process of scientific discovery.</em> <p>As I said, Sagan is much better at saying it than most of us, but the reason most of us are in our fields is the wonder of it all. The wanting to know not just the what but the why and the sheer delight in finding they why. The universe is a giant puzzle just waiting for us to figure it out and those of us in the sciences love figuring out puzzles. The universe and the natural world are amazing places if you start digging, full of enough wonder to keep anyone fulfilled.</p> Tue, 30 Dec 2014 18:07:27 -0700 On thermodynamics and evolution Often in my perusing of the internet, generally on Twitter, I come across some creationist espousing that the second law of thermodynamics as proof that evolution canít possibly happen. Now anyone with a grasp of thermodynamics knows that this ďargument?is a bunch of bovine scatology, but on Twitter it is hard to combat it more than with ďthe Earth isnít a closed system? With this in mind this post on what the laws of thermodynamics actually say and what they mean. Feel free to link here if you get the thermodynamics argument from a creationist. <p>To start, thermodynamics is the study of how heat flows in systems. It is immensely useful when designing pretty much anything that has to move as it deals with the limitations of how heat and work interact. It is also useful in physics in general as it can be to some extent expanded to energy flow in general. How this all works out will become clearer as we go through the various aspects of thermodynamics. </p><p> Now in general thermodynamics can be seen as a set of three-ish laws that in general terms set out how heat can flow in and out of systems. We will look at each of these in turn and see how they affect the ability of order to come from chaos. </p><p> The first law we will look at is actually called the Zeroth Law of Thermodynamics. Some definitions:</p><p> <em>If bodies A and B are each in thermal equilibrium with a third body T, they are in thermal equilibrium with each other.</em> (Halliday &amp; Resnick 1988, p448)</p><p> <em>The zeroth law of thermodynamics states that when two bodies have equality of temperature with a third body, then in turn they have equality of temperature with each other.</em> (Van Wylen &amp; Sonntag 1973, p33)</p> <p> So what does this mean? Simply put if two systems are in thermal equilibrium (that is, the same temperature as) a third system, then the two original systems are in thermal equilibrium with each other. In other words if system A is touching system B and system C is touching system B but system A and C are not touching each other; and further if A and B are the same temperature and B and C are the same temperature then A and C are also the same temperature. The implication of this will become more apparent as we look at the second law.</p> <p>The next law, the First Law of Thermodynamics (second in order) deals with the creation and destruction of heat:</p><p> <em>during any cycle a system undergoes, the cyclic integral of the heat is proportional to the cyclic integral of the work.<em> (Van Wylen &amp; Sonntag 1973, p 90)</em></em></p><p> <em>The quantity Q-W is the same for all processes. It depends only on the initial and final states and it does not matter at all how you get from one to the other.<em> (Halliday &amp; Resnick, 1988 p469)</em></em></p> <p> Mathematically the first law is stated thus:<br /> [image1]<br /> Where delta U is the change in the internal energy of the system, Q is the heat in the system and W is the work done by the system.</p> <p>This is basically the law of conservation of energy, that is the amount of energy in an isolated system is constant. If the heat of the system increases, the work done by the system decreases and vice versa. In simpler terms you canít get more work out of a system than energy you put into the system. This law puts the ultimate limit on fuel economy for example. There is only so much energy in a litre of gasoline and even if the car is 100% efficient at converting that energy in to movement, the car will still only get a finite amount of kilometres per litre of fuel.</p> <p> Now the Second Law of Thermodynamics can be broken down into a few parts. Firstly:</p><p> <em>The second law of thermodynamics, statement A: It is impossible to extract heat from a system and convert it wholly into work with out causing other changes in the universe.<em> (Radin &amp; Folk 1982 p 336)</em></em></p><p> <em>Second law - first form: It is not possible to change heat completely into work, with no other change taking place.<em> (Halliday &amp; Resnick 1988, p510)</em></em></p> <p> Basically the first part of the second law says that you canít convert energy into work with 100% efficiency. That is there will be some loss of the energy to the environment through some mechanism, usually friction. This is the part of thermodynamics that prevents the creation of perpetual motion machines for example. There is always something that is going to steal some of your energy away, be it friction or gravity. Itís all a matter of degree.</p> <p> In mathematical terms the first part of the second law looks like this:<br /> [image2] </p> <p> In this case e is the efficiency of the heat engine in percent. W is the useful work out of the engine which is also equal to the total heat used by the system (Q_H) minus the heat lost to the environment (Q_C). The work is divided by the total heat used by the system (Q_H) to get the efficiency.</p> <p> Now the second part of the second law of thermodynamics goes like this:</p><p> <em> The second law of thermodynamics, statement B: Heat can never, of itself, flow from a lower to a higher temperature.</em> (Radin &amp; Folk 1982, p 337)</p><p> <em> Second law - second form: It is not possible for heat to flow from one body to another body at a higher temperature, with no other change taking place.</em> (Halliday &amp; Resnick, 1988, p512)</p> <p> So what does this mean? Quite simply it means that heat always moves from hot objects to cool objects and not the other way around. That is a cold object will suck heat out of a hot object until they are in thermal equilibrium (i.e. at the same temperature). Of course it is possible to move heat from a cold object to a warm object, our refrigerators do it all the time, but doing so requires energy from an outside source.</p> <p>This brings us to the last part of the Second Law:</p><p> <em> The second law of thermodynamics statement c: (i) The integral of [image3] is the same for all reversible processes between the same states. (ii) The total entropy change in any given process is positive or zero.</em> (Radin &amp; Folk 1982, p 345)</p><p> <em> isolated systems tend toward disorder and entropy is a measure of this disorder. </em>(Serway &amp; Faughn, 1986)</p> <p> What this means is that the random disorder in a system, that is the heat of a system, must increase or stay the same over time. The key here is that the system be in isolation. If the system isnít isolated (or closed) then the disorder can be reduced (as is the case in a refrigerator) by the application of energy to transfer the entropy somewhere else.</p> <p> So how does this relate to creationist ďargument?that the Second Law of Thermodynamics prevents evolution as greater order goes against entropy? Well as far as I can tell the ďargument?goes something like this:<br /> </p><ol> <li>The Second Law of Thermodynamics says entropy has to increase</li> <li>Since entropy is disorder, disorder must therefore increase</li> <li>Evolution says complexity came from simplicity</li> <li>Since disorder has to increase, complexity canít come from simplicity therefore some form of god has to intervene</li> </ol> <p> Now let us look at this step-by-step. First looking at the Second Law of thermodynamics argument. The statement that the Second Law says that entropy must increase is only partially true. As Iíve shown above entropy only tends to increase and that the application of energy can cause entropy to shift around. That is entropy can be made to move from an area of higher entropy to an area of lower entropy by applying energy. Again as Iíve provided above, a simple example is the lowly refrigerator. In the refrigerator the items inside are made cooler than the surrounding environment. Taking the creationist argument about entropy this is impossible. Which it is if there wasnít energy being input into the system that we call a refrigerator. This energy allows the refrigerator to pump heat (and thus entropy) against the gradient, that is from cold to hot, or from disorder to order. So by stating that entropy has to increase, the creationist is only half telling the truth. As long as thereís energy available, entropy can be moved from place to place or at least be held at bay.</p> <p>This effectively destroys the first and second premises of the creationist argument. The Earth isnít a closed system. There is continual energy input from the Sun. A lot of energy input ?to the tune of about 1.7e17 J of energy per second over the whole lit surface of the Earth. Thatís about 170000 Terawatts of power. Thatís ample energy to create order from disorder.</p> <p> At this point the craftier creationists will then claim that the universe is a closed system so that their half-interpretation of the Second Law still holds. Well yes, except that thereís those pesky stars pumping energy into the system again, and gravity giving everything gravitational potential energy. The reality is that as long as there is something pumping energy into the universe, there will be the ability to hold the line on the amount of entropy in the universe. Also missing from their argument is that the universe is incredibly big. It can absorb a heck of a lot of entropy before things start falling apart. The reality is that the universe wonít undergo itís ultimate heat death, that is the universe moving to thermal equilibrium until the last of the black holes evaporates which is on the order of a googol years from now.</p> <p> At this point some creationist wiz will break out the First Law (in itís guise as the conservation of energy) and state that energy canít be created or destroyed. Which is true but these same creationists for some reason forget that matter is also a form of energy. Stars get their vast amounts of energy from converting a little be of matter from each nuclear fusion reaction into energy. So the star gets a little lighter and pumps out some more entropy defeating energy. In practical terms the stars are taking the entropy around them and transferring it to their cores. In the end the stars run out of convertible matter and they die, releasing heavy elements to the cosmos where gravity will pull it all together again to form another star and possibly some planets.</p> <p> So where does this leave the creationist argument? Well premise 3 depends on the veracity of premises 1 and 2, and since premises 1 and 2 are complete nonsense if you look at the whole of the laws of thermodynamics (not just the bit that you think are the laws of thermodynamics) premise 3 also collapses. This leaves the conclusion at 4 with nothing to stand on. </p> <p> To sum all this up, if you come across someone using the laws of thermodynamics to refute a perpetual motion machine, then youíve probably come across someone with some grounding in physics and the laws of thermodynamics. On the other hand if you come across someone who thinks the laws of thermodynamics would prevent evolution from happening, then youíve come across someone who has no idea whatsoever about physics and thermodynamics.</p> <p> </p><p> <b>References</b><br /> Halliday, D. and Resnick, R., 1988, Fundamentals of Physics, 3rd ed., New York, Wiley<br /> Radin, S.H. and Folk, R.T., 1982, Physics for Scientists and Engineers, Englewood Cliffs, Prentice-Hall<br /> Serway, R.A. and Faughn, J., 1985, College Physics, Philadelphia, Saunders<br /> Van Wylen, G.J. and Sonntag, R.E., 1973, Fundamentals of Classical Thermodynamics, New York, Wiley</p> Wed, 12 Nov 2014 23:11:05 -0700