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#1




Most 'Variable Stars' are not Varying at all..
They are ordinary stars that have a large orbiting planet.
Their light moves at c+vsin(t/T) towards Earth, causing the photon stream to spatially bunch up and separate as it travels. This gives the impression of a periodic brightness variation when it reaches an Earth observer. For a complete discription of the process see: http://www.scisite.info/The_new_ball..._of_light.html 
#2




Most 'Variable Stars' are not Varying at all..
"Henry Wilson DSc" Hw@.. wrote in message ...  They are ordinary stars that have a large orbiting planet.  Their light moves at c+vsin(t/T) Even if the orbit were perfectly circular (which in most cases it is not) the function would give an initial velocity of c+v.sin(t/period modulo 2pi), you need to convert t/period to a pure number for dimensional analysis and then convert to radians to become the argument of the function sin() (or cos(), depending on your arbitrary choice of axes). So T must be the period (symbol P) and t must lie between 0 and 2pi. If the orbit is inclined the light moves at c+v.cos(inclination).sin(t/P mod 2pi), again for a circular orbit. If a starting point is defined for periapsis (not relevant for circular orbits, but needed for elliptical orbits) then the equation becomes c+v.cos(inclination).sin( [phi + t/P] mod 2pi), where phi is the angle of periapsis to the line of sight. For elliptical orbits the sin function cannot be used except as an approximation.  towards Earth, causing the photon stream to  spatially bunch up and separate as it travels. This gives the impression of a  periodic brightness variation when it reaches an Earth observer.   For a complete discription of the process see:  The word you seek is "description". 
#3




Most 'Variable Stars' are not Varying at all..
On Fri, 11 Mar 2011 02:37:54 0000, "Androcles"
wrote: . "Henry Wilson DSc" Hw@.. wrote in message .. .  They are ordinary stars that have a large orbiting planet.  Their light moves at c+vsin(t/T) Even if the orbit were perfectly circular (which in most cases it is not) the function would give an initial velocity of c+v.sin(t/period modulo 2pi), you need to convert t/period to a pure number for dimensional analysis and then convert to radians to become the argument of the function sin() (or cos(), depending on your arbitrary choice of axes). t/T IS already a pure number. The 2pi turns it into a phase angle, in radians....also a pure number...I usually leave out the 2pi because it is understood. So T must be the period (symbol P) and t must lie between 0 and 2pi. We know the correct equation is c + v(cos(2pi.t/T), where v is the radial velocity. That means it already includes cos(pitch) If the orbit is inclined the light moves at c+v.cos(inclination).sin(t/P mod 2pi), again for a circular orbit. If a starting point is defined for periapsis (not relevant for circular orbits, but needed for elliptical orbits) then the equation becomes c+v.cos(inclination).sin( [phi + t/P] mod 2pi), where phi is the angle of periapsis to the line of sight. For elliptical orbits the sin function cannot be used except as an approximation. Of course...  towards Earth, causing the photon stream to  spatially bunch up and separate as it travels. This gives the impression of a  periodic brightness variation when it reaches an Earth observer.   For a complete discription of the process see:  The word you seek is "description". 
#4




Most 'Variable Stars' are not Varying at all..
"Henry Wilson DSc" Hw@.. wrote in message ...  On Fri, 11 Mar 2011 02:37:54 0000, "Androcles"  wrote:   .  "Henry Wilson DSc" Hw@.. wrote in message  .. .   They are ordinary stars that have a large orbiting planet.   Their light moves at c+vsin(t/T)   Even if the orbit were perfectly circular (which in most cases it is not)  the function would give an initial velocity of c+v.sin(t/period modulo 2pi),  you need to convert t/period to a pure number for dimensional analysis  and then convert to radians to become the argument of the function sin()  (or cos(), depending on your arbitrary choice of axes).   t/T IS already a pure number. The 2pi turns it into a phase angle, in  radians....also a pure number...I usually leave out the 2pi because it is  understood. What you call T is the period, P. When I wrote Doolin'sStar I used T for the APPARENT time interval. http://www.androcles01.pwp.blueyonder.co.uk/Doolin'sStar.GIF You are not helping by changing the definition of variables.  So T must be the  period (symbol P) and t must lie between 0 and 2pi.   We know the correct equation is c + v(cos(2pi.t/T), where v is the radial  velocity. That means it already includes cos(pitch) *I* know that v is your sqrt(vellx^2 + velly^2), see sheet 2 of http://www.androcles01.pwp.blueyonde...lsonMethod.xls because Wilson's Wobbly Worbits are Wedgeon and v does not include cos(pitch).   If the orbit is inclined the light moves at  c+v.cos(inclination).sin(t/P mod 2pi), again for a circular orbit.  If a starting point is defined for periapsis (not relevant for circular  orbits,  but needed for elliptical orbits) then the equation becomes  c+v.cos(inclination).sin( [phi + t/P] mod 2pi), where phi is the angle  of periapsis to the line of sight. For elliptical orbits the sin function  cannot be used except as an approximation.   Of course... Ok, so v isn't the radial velocity, it is the orbital velocity composed of vellx and velly, and P is the period, not T. I'm not saying you are wrong, I'm saying we need to be consistent and clear. When writing a paper or a program, the first thing is to list definitions so that we all know what they mean. Radial velocity = c+v.cos(psi).sin([phi + t/P] mod 2pi). psi = 0 for edge on. psi and phi are constants.    towards Earth, causing the photon stream to   spatially bunch up and separate as it travels. This gives the impression  of a   periodic brightness variation when it reaches an Earth observer.     For a complete discription of the process see:    The word you seek is "description".   
#5




Most 'Variable Stars' are not Varying at all..
On Mar 10, 1:35*pm, Hw@..(Henry Wilson DSc) wrote:
They are ordinary stars that have a large orbiting planet. Their light moves at c+vsin(t/T) towards Earth, causing the photon stream to spatially bunch up and separate as it travels. This gives the impression of a periodic brightness variation when it reaches an Earth observer. For a complete discription of the process see: http://www.scisite.info/The_new_ball..._of_light.html Exactly correct, whereas a binary star such as having a brown dwarf or a very large 16x Mj planet should make a good starshade as it orbits through our line of sight. Basically most stars have planets, at least to start with. http://translate.google.com/# Brad Guth, Brad_Guth, Brad.Guth, BradGuth, BG / “Guth Usenet” 
#6




Most 'Variable Stars' are not Varying at all..
On Fri, 11 Mar 2011 22:15:32 0000, "Androcles"
wrote: "Henry Wilson DSc" Hw@.. wrote in message .. .  On Fri, 11 Mar 2011 02:37:54 0000, "Androcles"  wrote:  Even if the orbit were perfectly circular (which in most cases it is not)  the function would give an initial velocity of c+v.sin(t/period modulo 2pi),  you need to convert t/period to a pure number for dimensional analysis  and then convert to radians to become the argument of the function sin()  (or cos(), depending on your arbitrary choice of axes).   t/T IS already a pure number. The 2pi turns it into a phase angle, in  radians....also a pure number...I usually leave out the 2pi because it is  understood. What you call T is the period, P. When I wrote Doolin'sStar I used T for the APPARENT time interval. http://www.androcles01.pwp.blueyonder.co.uk/Doolin'sStar.GIF You are not helping by changing the definition of variables. Let's not argue about trivialities, chief. When you adjust your time axis for arrival time of each sample 'bunch' your program will produce the same curves that mine does.  So T must be the  period (symbol P) and t must lie between 0 and 2pi.   We know the correct equation is c + v(cos(2pi.t/T), where v is the radial  velocity. That means it already includes cos(pitch) *I* know that v is your sqrt(vellx^2 + velly^2), see sheet 2 of http://www.androcles01.pwp.blueyonde...lsonMethod.xls because Wilson's Wobbly Worbits are Wedgeon and v does not include cos(pitch). Cos pitch is included in my velocity value. that should be obvious.  If the orbit is inclined the light moves at  c+v.cos(inclination).sin(t/P mod 2pi), again for a circular orbit.  If a starting point is defined for periapsis (not relevant for circular  orbits,  but needed for elliptical orbits) then the equation becomes  c+v.cos(inclination).sin( [phi + t/P] mod 2pi), where phi is the angle  of periapsis to the line of sight. For elliptical orbits the sin function  cannot be used except as an approximation.   Of course... Ok, so v isn't the radial velocity, it is the orbital velocity composed of vellx and velly, and P is the period, not T. The usual convention for period in for instance, the traveling wave equation is the agreek letter Tor, which is replaced by T in ascii. I'm not saying you are wrong, I'm saying we need to be consistent and clear. When writing a paper or a program, the first thing is to list definitions so that we all know what they mean. Radial velocity = c+v.cos(psi).sin([phi + t/P] mod 2pi). psi = 0 for edge on. psi and phi are constants. I have explained how all orbit configurations can be accomodated by using edge on ones. I also expect my readers to be able to understand what my (few) equations imply. 
#7




Most 'Variable Stars' are not Varying at all..
On Fri, 11 Mar 2011 15:08:00 0800 (PST), Brad Guth wrote:
On Mar 10, 1:35*pm, Hw@..(Henry Wilson DSc) wrote: They are ordinary stars that have a large orbiting planet. Their light moves at c+vsin(t/T) towards Earth, causing the photon stream to spatially bunch up and separate as it travels. This gives the impression of a periodic brightness variation when it reaches an Earth observer. For a complete discription of the process see: http://www.scisite.info/The_new_ball..._of_light.html Exactly correct, whereas a binary star such as having a brown dwarf or a very large 16x Mj planet should make a good starshade as it orbits through our line of sight. Basically most stars have planets, at least to start with. and the planets cause the stars to wobble around a barycentre in a fairly small orbit. That is enough to cause photon bunching as their emitted light travels across space. http://translate.google.com/# Brad Guth, Brad_Guth, Brad.Guth, BradGuth, BG / “Guth Usenet” 
#8




Most 'Variable Stars' are not Varying at all..
"Henry Wilson DSc" Hw@.. wrote in message ...  On Fri, 11 Mar 2011 22:15:32 0000, "Androcles"  wrote:    "Henry Wilson DSc" Hw@.. wrote in message  .. .   On Fri, 11 Mar 2011 02:37:54 0000, "Androcles"   wrote:    Even if the orbit were perfectly circular (which in most cases it is not)   the function would give an initial velocity of c+v.sin(t/period modulo  2pi),   you need to convert t/period to a pure number for dimensional analysis   and then convert to radians to become the argument of the function sin()   (or cos(), depending on your arbitrary choice of axes).     t/T IS already a pure number. The 2pi turns it into a phase angle, in   radians....also a pure number...I usually leave out the 2pi because it is   understood.   What you call T is the period, P.  When I wrote Doolin'sStar I used T for the APPARENT time interval.  http://www.androcles01.pwp.blueyonder.co.uk/Doolin'sStar.GIF  You are not helping by changing the definition of variables.   Let's not argue about trivialities, chief. When you adjust your time axis for  arrival time of each sample 'bunch' your program will produce the same curves  that mine does. Yes, but now that we agree on the principles involved it is time to step back, look around and tidy up the mess left behind. That's what you are writing about, so let's cross the 't's and dot the 'i's and leave a neat and tidy theory without any loose ends.   So T must be the   period (symbol P) and t must lie between 0 and 2pi.     We know the correct equation is c + v(cos(2pi.t/T), where v is the radial   velocity. That means it already includes cos(pitch)   *I* know that v is your sqrt(vellx^2 + velly^2), see sheet 2 of  http://www.androcles01.pwp.blueyonde...lsonMethod.xls  because Wilson's Wobbly Worbits are Wedgeon and v does not  include cos(pitch).   Cos pitch is included in my velocity value. that should be obvious. Obvious to you but it isn't obvious to others. The orbital velocity isn't even close to the radial velocity, yet you want to call both of them v. You know what you mean but nobody else does. Look, if I go into a shop in Britain to make a purchase, the price on the sticker is the price I pay and it includes value added tax (VAT). That should be obvious. But if I go into a shop in the USA to make a purchase, the price on the sticker does NOT include sales tax. I have to pay more than the sticker price. That should be obvious. Two different conventions are never "obvious". The date today in Britain is 12/3/2011, obviously. The date today in the USA is 3/12/2011, obviously. No, it is not the 3rd of December yet, it is still the 12th of March. The USA has a conventional way of writing the date: month first, then day, then year. It's no good saying which is right and which is wrong, it is their convention, and anyway both are wrong, it should be year first as that is the most significant. But when in Rome, do as the Romans do. What you are saying is NOT obvious.    If the orbit is inclined the light moves at   c+v.cos(inclination).sin(t/P mod 2pi), again for a circular orbit.   If a starting point is defined for periapsis (not relevant for circular   orbits,   but needed for elliptical orbits) then the equation becomes   c+v.cos(inclination).sin( [phi + t/P] mod 2pi), where phi is the angle   of periapsis to the line of sight. For elliptical orbits the sin function   cannot be used except as an approximation.     Of course...   Ok, so v isn't the radial velocity, it is the orbital velocity composed  of vellx and velly, and P is the period, not T.   The usual convention for period in for instance, the traveling wave equation is  the agreek letter Tor, which is replaced by T in ascii. The greek letter is 'tau', not 'tor'. That is precisely the kind of ugly mess and confusion you are leaving behind that I'm talking about. The relativists confuse t, tau and t' because they are following their own convention and think it is obvious, but Einstein has a clear distinction between x, x' and xi and does not use t' at all. That's how the arguments begin. We are talking here about the time to complete an orbit, and that means there is a oneone mapping from t/P to angle. We are not discussing a ****ing wave equation.   I'm not saying you are wrong, I'm saying we need to be consistent  and clear. When writing a paper or a program, the first thing is to  list definitions so that we all know what they mean.  Radial velocity = c+v.cos(psi).sin([phi + t/P] mod 2pi).  psi = 0 for edge on. psi and phi are constants.   I have explained how all orbit configurations can be accomodated by using edge  on ones. I also expect my readers to be able to understand what my (few)  equations imply.  It's ok to have few equations. Indeed, the fewer the better. It is not ok to embed cos(psi) in v.sin(phi+t/P) and then assume it is "obvious". The time has come to be clear and concise, you are now at the writing stage, and I expect you to be able to understand common ****ing sense. Why is it difficult for you to understand other people are not going to make your assumptions? Britain: price includes VAT. Round the price up, take off a penny, it's £4.99 inc VAT. I get a penny change from a £5 note. USA: price does NOT include sales tax. Round the price up, take off a penny, it's $4.99 + tax = $5.34, let the purchaser know how much his government is charging. I need another few cents to pay for my chocolate and now I'm embarrassed, I don't have enough change and didn't understand the "obvious" convention. 
#9




Most 'Variable Stars' are not Varying at all..
On Mar 12, 12:19*am, Hw@..(Henry Wilson DSc) wrote:
On Fri, 11 Mar 2011 15:08:00 0800 (PST), Brad Guth wrote: On Mar 10, 1:35 pm, Hw@..(Henry Wilson DSc) wrote: They are ordinary stars that have a large orbiting planet. Their light moves at c+vsin(t/T) towards Earth, causing the photon stream to spatially bunch up and separate as it travels. This gives the impression of a periodic brightness variation when it reaches an Earth observer. For a complete discription of the process see: http://www.scisite.info/The_new_ball..._of_light.html Exactly correct, whereas a binary star such as having a brown dwarf or a very large 16x Mj planet should make a good starshade as it orbits through our line of sight. *Basically most stars have planets, at least to start with. and the planets cause the stars to wobble around a barycentre in a fairly small orbit. That is enough to cause photon bunching as their emitted light travels across space. http://translate.google.com/# Brad Guth, Brad_Guth, Brad.Guth, BradGuth, BG / Guth Usenet Sounds good to me. Imagine what a star would wobble if it had a neutron binary partner, or even two identical stars in lockstep with one another (especially when viewed on edge). For a whole star to vary on it's own seems highly unlikely, if not impossible. http://translate.google.com/# Brad Guth, Brad_Guth, Brad.Guth, BradGuth, BG / “Guth Usenet” 
#10




Most 'Variable Stars' are not Varying at all..
On Sat, 12 Mar 2011 09:49:24 0000, "Androcles"
wrote: "Henry Wilson DSc" Hw@.. wrote in message .. .  On Fri, 11 Mar 2011 22:15:32 0000, "Androcles"  wrote:   Even if the orbit were perfectly circular (which in most cases it is not)   the function would give an initial velocity of c+v.sin(t/period modulo  2pi),   you need to convert t/period to a pure number for dimensional analysis   and then convert to radians to become the argument of the function sin()   (or cos(), depending on your arbitrary choice of axes).     t/T IS already a pure number. The 2pi turns it into a phase angle, in   radians....also a pure number...I usually leave out the 2pi because it is   understood.   What you call T is the period, P.  When I wrote Doolin'sStar I used T for the APPARENT time interval.  http://www.androcles01.pwp.blueyonder.co.uk/Doolin'sStar.GIF  You are not helping by changing the definition of variables.   Let's not argue about trivialities, chief. When you adjust your time axis for  arrival time of each sample 'bunch' your program will produce the same curves  that mine does. Yes, but now that we agree on the principles involved it is time to step back, look around and tidy up the mess left behind. That's what you are writing about, so let's cross the 't's and dot the 'i's and leave a neat and tidy theory without any loose ends.   So T must be the   period (symbol P) and t must lie between 0 and 2pi.     We know the correct equation is c + v(cos(2pi.t/T), where v is the radial   velocity. That means it already includes cos(pitch)   *I* know that v is your sqrt(vellx^2 + velly^2), see sheet 2 of  http://www.androcles01.pwp.blueyonde...lsonMethod.xls  because Wilson's Wobbly Worbits are Wedgeon and v does not  include cos(pitch).   Cos pitch is included in my velocity value. that should be obvious. Obvious to you but it isn't obvious to others. The orbital velocity isn't even close to the radial velocity, yet you want to call both of them v. You don't get it. I first generate an ellipse, starting at the periastron. I plot 40000 points around the orbit spaced equally in time. At each point, the peripheral velocity and its angle relative to the direction of the minor axis are recorded in two arrays. The maximum speed, at the periastron is assigned the value one and all other speeds are expressed as a fraction. The same proportions hold for all ellipses of the same eccentricity. Yaw angle is that between the observer and the major axis. Adding that to the peripheral angle and multiplying by the peripheral speed gives the radial velocity for the edge on orbit. My 'Pitch' is then defined as rotation around an axis perpendicular to the LOS. Rotating the ellipse around that axis multiplues ALL the radial velocities by the same factor, cos(pitch). So pitch can be omitted from the equation. It is present in the velocity figure. You know what you mean but nobody else does. well they should try bit harder. ....but the same definitely applies to YOUR demos....they invariably have no accompanying explanations and are meaningless. Look, if I go into a shop in Britain to make a purchase, the price on the sticker is the price I pay and it includes value added tax (VAT). That should be obvious. But if I go into a shop in the USA to make a purchase, the price on the sticker does NOT include sales tax. I have to pay more than the sticker price. That should be obvious. Two different conventions are never "obvious". The date today in Britain is 12/3/2011, obviously. The date today in the USA is 3/12/2011, obviously. No, it is not the 3rd of December yet, it is still the 12th of March. The USA has a conventional way of writing the date: month first, then day, then year. It's no good saying which is right and which is wrong, it is their convention, and anyway both are wrong, it should be year first as that is the most significant. But when in Rome, do as the Romans do. What you are saying is NOT obvious. very little of what YOU say or write has an 'obvious' meaning.  Ok, so v isn't the radial velocity, it is the orbital velocity composed  of vellx and velly, and P is the period, not T.   The usual convention for period in for instance, the traveling wave equation is  the agreek letter Tor, which is replaced by T in ascii. The greek letter is 'tau', not 'tor'. It was TOR when I was taught. Tau is something else. That is precisely the kind of ugly mess and confusion you are leaving behind that I'm talking about. The relativists confuse t, tau and t' because they are following their own convention and think it is obvious, but Einstein has a clear distinction between x, x' and xi and does not use t' at all. That's how the arguments begin. We are talking here about the time to complete an orbit, and that means there is a oneone mapping from t/P to angle. We are not discussing a ****ing wave equation. In physics, P stands for pressure. T for period.  I have explained how all orbit configurations can be accomodated by using edge  on ones. I also expect my readers to be able to understand what my (few)  equations imply.  It's ok to have few equations. Indeed, the fewer the better. It is not ok to embed cos(psi) in v.sin(phi+t/P) and then assume it is "obvious". The time has come to be clear and concise, you are now at the writing stage, and I expect you to be able to understand common ****ing sense. Why is it difficult for you to understand other people are not going to make your assumptions? Figure 1 shows and explains the principle quite clearly. Britain: price includes VAT. Round the price up, take off a penny, it's £4.99 inc VAT. I get a penny change from a £5 note. USA: price does NOT include sales tax. Round the price up, take off a penny, it's $4.99 + tax = $5.34, let the purchaser know how much his government is charging. I need another few cents to pay for my chocolate and now I'm embarrassed, I don't have enough change and didn't understand the "obvious" convention. 

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