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Requiem for Relativity
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16 years 9 months ago #12848
by Joe Keller
Replied by Joe Keller on topic Reply from
I'd like to get prospective photos of Barbarossa and Frey on film. CCD imaging has many advantages, but the spurious images that can arise on film probably are fewer and better understood.
Likely, Barbarossa and Frey are red. I've found them on all five Red and Optical Infrared sky surveys (scans of photographic plates), but not on the one Blue sky survey. They are dimmer than expected, so either are unexpectedly small, are surrounded by dust (which would redden them), or have unexpectedly low albedo, consistent with a strong color. Distant solar system objects typically are red (see above post).
For distant solar system objects, Tegler & Romanishin found B-V up to 1.24 and V-R up to 0.78. Consulting original sources, I find that Johnson & Morgan (ApJ 117:313, 1953, Table 3) found B-V = 1.16 and 1.48 for the standard K2III star betaOph and the standard K4III star betaCnc, resp. Kron, White & Gascoigne (ApJ 118:502, 1953, Table 4) found R magnitudes giving V-R = 0.54 and 0.76 for these stars, resp. So, the reddest common distant solar system objects, have about the B-V of a K2III star and the V-R of a K4III star. That is, they crudely resemble a K3III star. Straizys, "Multicolor Stellar Photometry", p. 51 and Figs. 11 & 12, gives 6000 & 8300 Angstrom for the smoothed spectral peak for K0III & K5III, resp. This interpolates to 7380 A for K3III. MS Bessel's abovementioned article in PASP, Fig. 1, shows that Red sky survey plates (R59F) cut off at 7000 A above, while the Optical Infrared sky survey plates (IsubN) cut off at 7000 below. Either plate would miss about half the radiation from Barbarossa or Frey, if these resemble the reddest objects cataloged by Tegler & Romanishin.
Two especially good advanced books on astrophotography are Covington's 1999 "Astrophotography for the Amateur" 2nd ed., and Wallis & Provin's 1988 "Manual of Advanced Celestial Photography". Covington's Table 10.1 lists "Kodak Ektachrome Professional E200" as in a 7-way tie for first place among 26 un-hypered films, for good reciprocity. It's in third place for sensitivity at (simulated alpha-hydrogen line, 6563 A) 6600 A. Neither of the two films besting it for red sensitivity, had very good un-hypered reciprocity.
Covington warns that a film's characteristics might change over the years due to changes in manufacture, or even change randomly from roll to roll. He also says that the designation "Professional" and the requirement that "Professional" film be refrigerated, have mainly to do with maintaining uniform color balance through consistent storage and aging procedures (for the sake of the portrait photographer) and little to do with qualities that are of interest to most astronomers.
Kodak's website (use the onsite search window) still lists "Kodak Professional Ektachrome E200". I'd suggest this film for photographing Barbarossa.
Infrared films have poor reciprocity, though this can be improved by hypering, particularly by distilled water hypering (Wallis & Provin). Two prime choices might be Konica IR750 (peak sensitivity 7500 A) and (if available) Agfa APX 200S (peak 7250 A). Kodak Technical Pan 2415 (it's B&W) hasn't been manufactured since several years prior to 2004, though has good far red sensitivity (with hypering) and reportedly stores well even for a decade without refrigeration.
Likely, Barbarossa and Frey are red. I've found them on all five Red and Optical Infrared sky surveys (scans of photographic plates), but not on the one Blue sky survey. They are dimmer than expected, so either are unexpectedly small, are surrounded by dust (which would redden them), or have unexpectedly low albedo, consistent with a strong color. Distant solar system objects typically are red (see above post).
For distant solar system objects, Tegler & Romanishin found B-V up to 1.24 and V-R up to 0.78. Consulting original sources, I find that Johnson & Morgan (ApJ 117:313, 1953, Table 3) found B-V = 1.16 and 1.48 for the standard K2III star betaOph and the standard K4III star betaCnc, resp. Kron, White & Gascoigne (ApJ 118:502, 1953, Table 4) found R magnitudes giving V-R = 0.54 and 0.76 for these stars, resp. So, the reddest common distant solar system objects, have about the B-V of a K2III star and the V-R of a K4III star. That is, they crudely resemble a K3III star. Straizys, "Multicolor Stellar Photometry", p. 51 and Figs. 11 & 12, gives 6000 & 8300 Angstrom for the smoothed spectral peak for K0III & K5III, resp. This interpolates to 7380 A for K3III. MS Bessel's abovementioned article in PASP, Fig. 1, shows that Red sky survey plates (R59F) cut off at 7000 A above, while the Optical Infrared sky survey plates (IsubN) cut off at 7000 below. Either plate would miss about half the radiation from Barbarossa or Frey, if these resemble the reddest objects cataloged by Tegler & Romanishin.
Two especially good advanced books on astrophotography are Covington's 1999 "Astrophotography for the Amateur" 2nd ed., and Wallis & Provin's 1988 "Manual of Advanced Celestial Photography". Covington's Table 10.1 lists "Kodak Ektachrome Professional E200" as in a 7-way tie for first place among 26 un-hypered films, for good reciprocity. It's in third place for sensitivity at (simulated alpha-hydrogen line, 6563 A) 6600 A. Neither of the two films besting it for red sensitivity, had very good un-hypered reciprocity.
Covington warns that a film's characteristics might change over the years due to changes in manufacture, or even change randomly from roll to roll. He also says that the designation "Professional" and the requirement that "Professional" film be refrigerated, have mainly to do with maintaining uniform color balance through consistent storage and aging procedures (for the sake of the portrait photographer) and little to do with qualities that are of interest to most astronomers.
Kodak's website (use the onsite search window) still lists "Kodak Professional Ektachrome E200". I'd suggest this film for photographing Barbarossa.
Infrared films have poor reciprocity, though this can be improved by hypering, particularly by distilled water hypering (Wallis & Provin). Two prime choices might be Konica IR750 (peak sensitivity 7500 A) and (if available) Agfa APX 200S (peak 7250 A). Kodak Technical Pan 2415 (it's B&W) hasn't been manufactured since several years prior to 2004, though has good far red sensitivity (with hypering) and reportedly stores well even for a decade without refrigeration.
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16 years 9 months ago #12653
by Joe Keller
Replied by Joe Keller on topic Reply from
In Covington's Oct. 2003 online revision of information in his 1999 2nd ed. text, he says:
"Kodak Elite Chrome 200 and Kodak Professional Ektachrome E200 Film are my favorites. (These two films are the same emulsion with slightly different aging.)
"This film has unusually good reciprocity characteristics (holds its speed well in long exposures) and unusually good response to emission nebulae (which come out bright cherry-red)."
Local photo shops only stock "Professional Elite Chrome 200". I bought two rolls, so I'll be ready to go.
I do find separate online Kodak technical data sheets, both dated 2005, for "Professional Ektachrome E200" and for "Professional Elite Chrome 200". The former data sheet has a section on push processing but the latter doesn't.
So, I would prefer "Professional Ektachrome E200". Covington says that of the two films, this is the one he has used the most; also, Covington's 1999 book says that push processing to 640 substantially increases its red response, while the data sheet on "Professional Elite Chrome 200" doesn't see fit to mention push processing at all.
Here's a Kodak expert quoted on a photography messageboard. He enthusiastically advocates push processing for Professional Ektachrome E200, but for the other film he is silent on the subject. On the other hand, he seems to imply that push processing would be superfluous, for Professional Elite Chrome 200:
(Aug. 2003)
"Here's the official response from Kodak:
'No, these two Kodak Films [Professional Ektachrome E200 vs. Elite Chrome 200] are very different. Kodak Elite Chrome 200 Film is inherently higher in color saturation and contrast, while Kodak Professional Ektachrome E200 Film, shot at EI 200, is pretty flat. However, the E200 pushed even 1-stop to EI 320, nicely increases in color saturation and contrast without adversely impacting color accuracy or grain. You can actually shoot this film all the way out to EI 1000 with excellent results. ...
-Peter V.
Kodak Information and Technical Support
Kodak Professional
Ph. 800-242-2424 ext. 19 ' "
The two leading photo shops in Des Moines each told me on the phone today that they have a few rolls of Professional Ektachrome E200 in stock. I might call them again to confirm that their statement is accurate and that they still have it, before I drive to Des Moines.
Update June 23: I've visited two of the three leading photo shops in this area. All three had just told me by phone that they had Professional Ektachrome E200. Neither of the two shops I actually visited, really had it. Both told me, or behaved as if I would assume, that Elite Chrome 200 is identical. According to Kodak, it most definitely isn't (see above). I bought some anyway at one of the shops, because it might be the best I can do, considering time limits.
This incident reminds me of the college student sitting next to me in the computer lab who told someone on his cell phone, "I have to hang up now, I have another call." Then, not caring that I and two other witnesses were learning that he was an habitual liar, he resumed working at the computer. There was no other call.
So a company that manufactures cell phones, maybe his cell phone, fired their safety officer, an epidemiologist who confirmed the cell phone - brain cancer link and refused to whitewash it. The college student tells little lies to his friends, the photo shop salesmen tell bigger lies to me, the cell phone manufacturer tells yet bigger lies to both of them. The big fish eat the little fish. Should we live like fish?
When lying becomes too widespread, speech becomes valueless. The statement of something, ceases to have any correlation with the likelihood that it is true. One knows no more after hearing a statement, than one did before. The speaker might as well not speak at all.
"Kodak Elite Chrome 200 and Kodak Professional Ektachrome E200 Film are my favorites. (These two films are the same emulsion with slightly different aging.)
"This film has unusually good reciprocity characteristics (holds its speed well in long exposures) and unusually good response to emission nebulae (which come out bright cherry-red)."
Local photo shops only stock "Professional Elite Chrome 200". I bought two rolls, so I'll be ready to go.
I do find separate online Kodak technical data sheets, both dated 2005, for "Professional Ektachrome E200" and for "Professional Elite Chrome 200". The former data sheet has a section on push processing but the latter doesn't.
So, I would prefer "Professional Ektachrome E200". Covington says that of the two films, this is the one he has used the most; also, Covington's 1999 book says that push processing to 640 substantially increases its red response, while the data sheet on "Professional Elite Chrome 200" doesn't see fit to mention push processing at all.
Here's a Kodak expert quoted on a photography messageboard. He enthusiastically advocates push processing for Professional Ektachrome E200, but for the other film he is silent on the subject. On the other hand, he seems to imply that push processing would be superfluous, for Professional Elite Chrome 200:
(Aug. 2003)
"Here's the official response from Kodak:
'No, these two Kodak Films [Professional Ektachrome E200 vs. Elite Chrome 200] are very different. Kodak Elite Chrome 200 Film is inherently higher in color saturation and contrast, while Kodak Professional Ektachrome E200 Film, shot at EI 200, is pretty flat. However, the E200 pushed even 1-stop to EI 320, nicely increases in color saturation and contrast without adversely impacting color accuracy or grain. You can actually shoot this film all the way out to EI 1000 with excellent results. ...
-Peter V.
Kodak Information and Technical Support
Kodak Professional
Ph. 800-242-2424 ext. 19 ' "
The two leading photo shops in Des Moines each told me on the phone today that they have a few rolls of Professional Ektachrome E200 in stock. I might call them again to confirm that their statement is accurate and that they still have it, before I drive to Des Moines.
Update June 23: I've visited two of the three leading photo shops in this area. All three had just told me by phone that they had Professional Ektachrome E200. Neither of the two shops I actually visited, really had it. Both told me, or behaved as if I would assume, that Elite Chrome 200 is identical. According to Kodak, it most definitely isn't (see above). I bought some anyway at one of the shops, because it might be the best I can do, considering time limits.
This incident reminds me of the college student sitting next to me in the computer lab who told someone on his cell phone, "I have to hang up now, I have another call." Then, not caring that I and two other witnesses were learning that he was an habitual liar, he resumed working at the computer. There was no other call.
So a company that manufactures cell phones, maybe his cell phone, fired their safety officer, an epidemiologist who confirmed the cell phone - brain cancer link and refused to whitewash it. The college student tells little lies to his friends, the photo shop salesmen tell bigger lies to me, the cell phone manufacturer tells yet bigger lies to both of them. The big fish eat the little fish. Should we live like fish?
When lying becomes too widespread, speech becomes valueless. The statement of something, ceases to have any correlation with the likelihood that it is true. One knows no more after hearing a statement, than one did before. The speaker might as well not speak at all.
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16 years 9 months ago #12186
by Joe Keller
Replied by Joe Keller on topic Reply from
Infrared and Extended-Red Films Banned by Homeland Security?
Stanford-trained journalist Linda Howe says, that a Midwestern U.S. college photography professor told her, that the big New York photography stores told him, that U.S. Homeland Security has banned the sale of infrared cameras. The professor speculated that this ban extends to infrared film. I don't know about the cameras, but the film seems to be available despite the general contraction of the film market.
Earlier this year Kodak discontinued its IR film, which was called "HIE". I saw one seller on eBay, but the price was "gouging": $47/roll including shipping. This film has about the same IR range as standard astronomical "optical IR" plates. (I saw another discontinued film of interest, Kodak Technical Pan 2415, on eBay with three sellers, for, e.g., $15/roll incl. shipping: not gouging prices.)
Maco IR820c (range - not peak - to 8200 A, and spectral response rather flat from ~4500 to ~8100 A; not as deep IR as Kodak HIE, but closer to it than any rival, though slower) seems to have disappeared from the market too. I checked the websites of New York and Chicago dealers which the current Cachet Co. website lists as carrying their Maco infrared film. None of them now lists it. Maybe this is only a failure to update Cachet's website. The Freestyle Co. in Hollywood sells Efke IR820, which is advertised as the same thing as the Maco but by a different manufacturer, so, I ordered some.
My internet search indicates that the abovementioned "extended-red" (basically, semi-IR) B&W films, Konica IR750 (peak at 7500 A) and Agfa APX 200S (peak at 7250 A), can't be found anywhere by anyone. A Des Moines photo shop told me Agfa is defunct. The New York office of Konica told me Konica quit making film.
Another extended-red B&W film, Ilford SFX200 (peak at 7200 A, flat to ~7300 A) has resumed production and is available from Freestyle too. I ordered some, though it's said that this film has especially bad reciprocity failure. Freestyle sells yet another extended-red B&W film, Rollei 400iso (flat to ~7000 A), which I also ordered.
Update Apr. 1, 2008. I got this email today from a major U.S. vendor of IR cameras:
"In regards to the ban of IR cameras, I have not heard anything about this and believe this just may be a rumor. We do have products that are export restricted but IR cameras are definitely not banned by DHS. Let me know if you have any questions.
Regards, Paul Neak
Rental Program Manager
FLIR Systems, Inc.
978-901-820 "
(Also, restrictions on the sale of IR cameras, might be part of the U.S. Army's "owning the night" strategy in Iraq & Afghanistan. IR cameras sold in the U.S. might find their way to the enemy.)
Stanford-trained journalist Linda Howe says, that a Midwestern U.S. college photography professor told her, that the big New York photography stores told him, that U.S. Homeland Security has banned the sale of infrared cameras. The professor speculated that this ban extends to infrared film. I don't know about the cameras, but the film seems to be available despite the general contraction of the film market.
Earlier this year Kodak discontinued its IR film, which was called "HIE". I saw one seller on eBay, but the price was "gouging": $47/roll including shipping. This film has about the same IR range as standard astronomical "optical IR" plates. (I saw another discontinued film of interest, Kodak Technical Pan 2415, on eBay with three sellers, for, e.g., $15/roll incl. shipping: not gouging prices.)
Maco IR820c (range - not peak - to 8200 A, and spectral response rather flat from ~4500 to ~8100 A; not as deep IR as Kodak HIE, but closer to it than any rival, though slower) seems to have disappeared from the market too. I checked the websites of New York and Chicago dealers which the current Cachet Co. website lists as carrying their Maco infrared film. None of them now lists it. Maybe this is only a failure to update Cachet's website. The Freestyle Co. in Hollywood sells Efke IR820, which is advertised as the same thing as the Maco but by a different manufacturer, so, I ordered some.
My internet search indicates that the abovementioned "extended-red" (basically, semi-IR) B&W films, Konica IR750 (peak at 7500 A) and Agfa APX 200S (peak at 7250 A), can't be found anywhere by anyone. A Des Moines photo shop told me Agfa is defunct. The New York office of Konica told me Konica quit making film.
Another extended-red B&W film, Ilford SFX200 (peak at 7200 A, flat to ~7300 A) has resumed production and is available from Freestyle too. I ordered some, though it's said that this film has especially bad reciprocity failure. Freestyle sells yet another extended-red B&W film, Rollei 400iso (flat to ~7000 A), which I also ordered.
Update Apr. 1, 2008. I got this email today from a major U.S. vendor of IR cameras:
"In regards to the ban of IR cameras, I have not heard anything about this and believe this just may be a rumor. We do have products that are export restricted but IR cameras are definitely not banned by DHS. Let me know if you have any questions.
Regards, Paul Neak
Rental Program Manager
FLIR Systems, Inc.
978-901-820 "
(Also, restrictions on the sale of IR cameras, might be part of the U.S. Army's "owning the night" strategy in Iraq & Afghanistan. IR cameras sold in the U.S. might find their way to the enemy.)
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16 years 8 months ago #20728
by Stoat
Replied by Stoat on topic Reply from Robert Turner
Hi Joe, I got the new image from the Bradford but it bounced back when I tried to send it to you. I think that hotmail has a limit to attachment files. Anyway it said your mailbox was full. The zipped file is about 8 meg. Message me with an e mail address.
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16 years 8 months ago #12220
by Stoat
Replied by Stoat on topic Reply from Robert Turner
Hi Joe, thought you'd want the times of these two images, they're probably in the headers but I've not looked. 00:10 on Sunday 1 April 2007 (00:10:10 UTC)
01:44 on Wednesday 19 March 2008 (01:44:57 UTC)
That second one is about as close to the equinox as it gets, must bode well. No pun intended with the mention of Bode.[][8D]
01:44 on Wednesday 19 March 2008 (01:44:57 UTC)
That second one is about as close to the equinox as it gets, must bode well. No pun intended with the mention of Bode.[][8D]
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16 years 8 months ago #20730
by Joe Keller
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A Rapidly Precessing Orbit for Frey Around Barbarossa
The six pairs of Barbarossa/Frey data points conform well to an orbit whose apsides precess retrograde about 60 degrees per sidereal "month", on average. There are 17 numerical data: 2 celestial coordinates x 6, plus (6 minus 1) time intervals. The model contains only 10 adjustable parameters: the orientation of the orbital plane (2 parameters), the dimensions of the orbital ellipse (2 params.), the initial point on that ellipse (1), the initial orientation of the apses (1), the mean rate of precession of the apses (1), and that rate's sinusoidal variation (3). Here's how I estimate this orbit by elementary methods:
1. Graph all six presumed Freys relative to their Barbarossas, on the same sheet with all the Barbarossas at the origin. (Multiply RA degrees by cos(Decl).) Note that A2A (i.e., the line from A2, the 1954 Barbarossa, to A, the 1954 Frey) is the longest apparent radius, that CC9 is second longest apparent, and that these are (anti)parallel. Guess that Frey's orbital plane around Barbarossa, is tilted to our line of sight, about the axis A2A. JGSR (i.e., the line from Genebriera's 2007 Barbarossa, to Riley's 2007 Frey, only a few days later) is perpendicular to A2A, and JGSR is longer than B3B or D3D (the other radii which are roughly perpendicular to A2A). So, guess the orbital plane's tilt angle as arcsin(JGSR/A2A) = 37.5 deg, from edge-on to our line of sight (or following binary star convention, we could say 90-37.5 = 52.5 from face-on). The Barbarossa/Frey orbital plane also is inclined 22 deg to Barbarossa's path around the sun, for a total inclination, to the Barbarossa/sun orbital plane, of 43.5 deg.
2. Now calculate all the actual lengths and angles in the orbital plane. Assume a highly elliptical orbit whose plane is invariant but whose apsides precess retrograde, rapidly. For a first approximation, let's use the position vector itself as an estimate of the line of apsides. For the fairly long times C9E4 (i.e., the time from C9 to E4) and E4SR, we then can estimate the rates of precession, 15.4 & 27.1 deg/yr, resp.
3. Let's approximate Frey's orbit as a precessing ellipse. For e = 0.6, Frey would spend ~2/3 of its time beyond the semimajor axis distance. The two shortest of the six actual radii are those of B and C9, and these are almost equal. So, adjust them to exact equality, and assume they equal the semimajor axis (which is then 0.50 AU). Using the apsis precession rate C9E4 (estimated in #2, as 15.4 deg/yr) subtract the amount of apsis precession, from the actual angle between B & C9. Plot the ellipse. The eccentricity is e = 0.7393. Frey's Keplerian sidereal month, with this major axis, would be 3.736 Julian yr.
4. Assume that an outer moon, Freya, in a larger orbit nearly perpendicular to Frey's, and edge-on to our line of sight (maybe somehow forced to be nearly perpendicular to Barbarossa's nearly-circular orbital path, like a submerged pan dragged through water), causes Frey's apsis precession. Suppose Freya's mass equals Frey's and that there is no other mass in the Barbarossa system. That is, the total mass is 0.0103 solar masses (determined from Neptune precession resonance), and the masses Barbarossa:Frey:Freya = 0.8771:0.1229:0.1229 = 7:1:1. If Freya & Frey have 2:1 orbital resonance, then Freya's major axis is 0.83 AU (including the additional centripetal force, exerted on Freya, by Frey).
5. Consider the effect of apsis precession rate, on the shape of the precessing ellipse, for the case of very small eccentricity. If a turntable's frame of reference is to have the same forces as are exerted on Frey, there will have to be additional special forces in the turntable's surrounding fixed frame, to cancel Coriolis force and the apparent force due to change in the turntable's speed. Conservation of angular momentum in the turntable frame, and equality of centripetal and centrifugal forces, afford two algebraic equations in r, Omega (the ellipse, or rather circle, orbital frequency in the fixed frame) and omega (the turntable frequency), from which r is elimated to give Omega as a function of omega. Also, the effect of turntable acceleration, delta(omega), on the eccentricity and line of apsides, is estimated and considered.
6. Assume B & D are inbound; A, C9, E4 & SR outbound. Considering the relation between Freya's perturbation force on Frey, and Frey's on Freya, gives the cycle of Freya's apsis precession, as about 36 yr if Frey's cycle of apsis precession is 22 yr; this 36 yr also should be the period of variation of Frey's apsis precession rate. I performed one or two steps of a rapidly converging computation in which a more accurate description of the precessing ellipses, leads to a more accurate determination of the apses and of the sinusoidally varying precession rates, and in turn to an even more accurate description of the ellipses. Frey's precession rate varies approximately sinusoidally from almost zero, to about 36 deg/yr, almost the highest rate for which the nearly-circular case has a solution balancing forces and conserving angular momentum (see #5). The average precession rate is 16.4 deg/yr, i.e. 53 deg/ actual average sidereal month. The parameters of the sinusoidal variation of precession rate (mean, amplitude, frequency, and phase) are determined by the five apsis positions 1986-2007 (1986 & 1987 both are used up in determining the ellipse plus one apsis position), but as a test, the position at A (1954) conforms to the model, if the mean precession rate is reduced to 15.0 deg/yr. The six final calculated accurate ellipses have eccentricities from 0.637 to 0.683.
7. The time estimates for the motions BC9, C9E4, E4D, and E4SR all are too high, by 11.7%, 24.0%, 31.6%, and 20.7%, resp. Also, the model overestimates the time A2A-B3B by 20.7% (if 11+ orbits are assumed). The estimates C9E4 & E4SR should be most accurate, because these time intervals are nearly several whole anomalistic months. Roughly, BC9 is, timewise, the inner 1/3 of the ellipse and E4D the outer 2/3; weighting these by time, 1/3::2/3, gives 25.0%. These three numbers, 24.0%, 20.7%, and 25.0%, are so close that surely they tell us the amount by which the major axis of Frey originally has been overestimated; they correspond to an adjustment from 0.50, to 0.435 AU.
8. Averaging from 1986 to 2007, Frey's anomalistic month is 2.86 Julian yr, and its sidereal month 3.23 Julian yr. From #7, the Keplerian sidereal month (what the month would be if Freya disappeared) is 3.03 Julian yr (this needn't exactly equal the actual average sidereal month). Frey's apsis precession varies from 0 to 100 deg per (Frey) sidereal month (ave. 53 deg). By contrast, Luna's apsis precession is 3.0 deg per sidereal lunar month. A particular neutron star reportedly exhibits presumed relativistic apsis precession of 38 deg / cycle. However, published numerical computations confirm that Frey's rapid precession is roughly consistent with Freya's mass and orbit.
The six pairs of Barbarossa/Frey data points conform well to an orbit whose apsides precess retrograde about 60 degrees per sidereal "month", on average. There are 17 numerical data: 2 celestial coordinates x 6, plus (6 minus 1) time intervals. The model contains only 10 adjustable parameters: the orientation of the orbital plane (2 parameters), the dimensions of the orbital ellipse (2 params.), the initial point on that ellipse (1), the initial orientation of the apses (1), the mean rate of precession of the apses (1), and that rate's sinusoidal variation (3). Here's how I estimate this orbit by elementary methods:
1. Graph all six presumed Freys relative to their Barbarossas, on the same sheet with all the Barbarossas at the origin. (Multiply RA degrees by cos(Decl).) Note that A2A (i.e., the line from A2, the 1954 Barbarossa, to A, the 1954 Frey) is the longest apparent radius, that CC9 is second longest apparent, and that these are (anti)parallel. Guess that Frey's orbital plane around Barbarossa, is tilted to our line of sight, about the axis A2A. JGSR (i.e., the line from Genebriera's 2007 Barbarossa, to Riley's 2007 Frey, only a few days later) is perpendicular to A2A, and JGSR is longer than B3B or D3D (the other radii which are roughly perpendicular to A2A). So, guess the orbital plane's tilt angle as arcsin(JGSR/A2A) = 37.5 deg, from edge-on to our line of sight (or following binary star convention, we could say 90-37.5 = 52.5 from face-on). The Barbarossa/Frey orbital plane also is inclined 22 deg to Barbarossa's path around the sun, for a total inclination, to the Barbarossa/sun orbital plane, of 43.5 deg.
2. Now calculate all the actual lengths and angles in the orbital plane. Assume a highly elliptical orbit whose plane is invariant but whose apsides precess retrograde, rapidly. For a first approximation, let's use the position vector itself as an estimate of the line of apsides. For the fairly long times C9E4 (i.e., the time from C9 to E4) and E4SR, we then can estimate the rates of precession, 15.4 & 27.1 deg/yr, resp.
3. Let's approximate Frey's orbit as a precessing ellipse. For e = 0.6, Frey would spend ~2/3 of its time beyond the semimajor axis distance. The two shortest of the six actual radii are those of B and C9, and these are almost equal. So, adjust them to exact equality, and assume they equal the semimajor axis (which is then 0.50 AU). Using the apsis precession rate C9E4 (estimated in #2, as 15.4 deg/yr) subtract the amount of apsis precession, from the actual angle between B & C9. Plot the ellipse. The eccentricity is e = 0.7393. Frey's Keplerian sidereal month, with this major axis, would be 3.736 Julian yr.
4. Assume that an outer moon, Freya, in a larger orbit nearly perpendicular to Frey's, and edge-on to our line of sight (maybe somehow forced to be nearly perpendicular to Barbarossa's nearly-circular orbital path, like a submerged pan dragged through water), causes Frey's apsis precession. Suppose Freya's mass equals Frey's and that there is no other mass in the Barbarossa system. That is, the total mass is 0.0103 solar masses (determined from Neptune precession resonance), and the masses Barbarossa:Frey:Freya = 0.8771:0.1229:0.1229 = 7:1:1. If Freya & Frey have 2:1 orbital resonance, then Freya's major axis is 0.83 AU (including the additional centripetal force, exerted on Freya, by Frey).
5. Consider the effect of apsis precession rate, on the shape of the precessing ellipse, for the case of very small eccentricity. If a turntable's frame of reference is to have the same forces as are exerted on Frey, there will have to be additional special forces in the turntable's surrounding fixed frame, to cancel Coriolis force and the apparent force due to change in the turntable's speed. Conservation of angular momentum in the turntable frame, and equality of centripetal and centrifugal forces, afford two algebraic equations in r, Omega (the ellipse, or rather circle, orbital frequency in the fixed frame) and omega (the turntable frequency), from which r is elimated to give Omega as a function of omega. Also, the effect of turntable acceleration, delta(omega), on the eccentricity and line of apsides, is estimated and considered.
6. Assume B & D are inbound; A, C9, E4 & SR outbound. Considering the relation between Freya's perturbation force on Frey, and Frey's on Freya, gives the cycle of Freya's apsis precession, as about 36 yr if Frey's cycle of apsis precession is 22 yr; this 36 yr also should be the period of variation of Frey's apsis precession rate. I performed one or two steps of a rapidly converging computation in which a more accurate description of the precessing ellipses, leads to a more accurate determination of the apses and of the sinusoidally varying precession rates, and in turn to an even more accurate description of the ellipses. Frey's precession rate varies approximately sinusoidally from almost zero, to about 36 deg/yr, almost the highest rate for which the nearly-circular case has a solution balancing forces and conserving angular momentum (see #5). The average precession rate is 16.4 deg/yr, i.e. 53 deg/ actual average sidereal month. The parameters of the sinusoidal variation of precession rate (mean, amplitude, frequency, and phase) are determined by the five apsis positions 1986-2007 (1986 & 1987 both are used up in determining the ellipse plus one apsis position), but as a test, the position at A (1954) conforms to the model, if the mean precession rate is reduced to 15.0 deg/yr. The six final calculated accurate ellipses have eccentricities from 0.637 to 0.683.
7. The time estimates for the motions BC9, C9E4, E4D, and E4SR all are too high, by 11.7%, 24.0%, 31.6%, and 20.7%, resp. Also, the model overestimates the time A2A-B3B by 20.7% (if 11+ orbits are assumed). The estimates C9E4 & E4SR should be most accurate, because these time intervals are nearly several whole anomalistic months. Roughly, BC9 is, timewise, the inner 1/3 of the ellipse and E4D the outer 2/3; weighting these by time, 1/3::2/3, gives 25.0%. These three numbers, 24.0%, 20.7%, and 25.0%, are so close that surely they tell us the amount by which the major axis of Frey originally has been overestimated; they correspond to an adjustment from 0.50, to 0.435 AU.
8. Averaging from 1986 to 2007, Frey's anomalistic month is 2.86 Julian yr, and its sidereal month 3.23 Julian yr. From #7, the Keplerian sidereal month (what the month would be if Freya disappeared) is 3.03 Julian yr (this needn't exactly equal the actual average sidereal month). Frey's apsis precession varies from 0 to 100 deg per (Frey) sidereal month (ave. 53 deg). By contrast, Luna's apsis precession is 3.0 deg per sidereal lunar month. A particular neutron star reportedly exhibits presumed relativistic apsis precession of 38 deg / cycle. However, published numerical computations confirm that Frey's rapid precession is roughly consistent with Freya's mass and orbit.
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