#62
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This final posting is for a true Englishman - John Harrison.His
timekeeper for longitude is based on axial rotation of the Earth through 360 degrees in 24 hours even though a hybrid version was developed later based on stellar circumpolar navigation.The answer is before you as you look at a clock on the wall and even though digital clocks are common,people still love the way a clock keeps cyclical pace with the day through the motion of the Earth. It is true that scientists managed to bury the 24hour/360 deg equivalency but most people feel uncomfortable with the alternative value and with good reason,it is wrong.Being cruel to Harrison in his lifetime has morphed to being cruel to all humanity in ours and the value of English fairness must be measured in courage which corrects this awful scientific eyesore. Pay heed to Harrison and the values to which he set his wondrous instrument. "I think I may make bold to say," wrote Harrison, "that there is neither any other Mechanism or Mathematical thing in the World that is more beautiful or curious in texture than this my watch or timekeeper for the Longitude." John Harrison |
#63
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wrote:
This final posting is for a true Englishman - John Harrison. Agreed - a phenomenal achievement . If I look at a central point and then walk round it and, while I'm walking make a series, say 10, 360 degree axial rotations while I complete the orbit round the central point, there will only be two points where I complete the 360 degree turn and find myself facing the central point. I could make a clock, as Harrison did, that takes as its guide, a rotation from central point to central point or I could make a clock that takes as its guide a 360 degree rotation. The former is good for most things terrestrial (though it needs the equation of time to find the time I shall actually be facing the central point. The latter, 360 degree clock, is a more useful measurer for astronomy. Cheers Martin -- Martin Frey http://www.hadastro.org.uk N 51 02 E 0 47 |
#64
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Pete Lawrence wrote:
On Thu, 24 Feb 2005 08:12:10 GMT, Mark Ayliffe wrote: On or about 2005-02-23, Pete Lawrence illuminated us with: On 23 Feb 2005 10:11:47 -0800, wrote: [snip] Big topics contain big nuts... Aren't they called Snickers now? :-) Where does Marathon fit into this then? When you get to the dentist? Tim -- This is not my helicopter. |
#65
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Martin Frey wrote: wrote: This final posting is for a true Englishman - John Harrison. Agreed - a phenomenal achievement . If I look at a central point and then walk round it and, while I'm walking make a series, say 10, 360 degree axial rotations while I complete the orbit round the central point, there will only be two points where I complete the 360 degree turn and find myself facing the central point. I could make a clock, as Harrison did, that takes as its guide, a rotation from central point to central point or I could make a clock that takes as its guide a 360 degree rotation. The former is good for most things terrestrial (though it needs the equation of time to find the time I shall actually be facing the central point. The latter, 360 degree clock, is a more useful measurer for astronomy. Cheers Martin -- Martin Frey http://www.hadastro.org.uk N 51 02 E 0 47 You really need to speak to a sundialist who will confirm that the discrete values of minutes and seconds added to or subtracted from the noon determination via axial rotation are NOT accumulative *.All the minute and second values do is keep axial rotation pinned to the noon determination and kepp one 24 hour day ticking seamlessly into the next 24 hour day.Astronomers calibrate their clocks this way every noon,only Harrisons could maintain that accuracy over long periods which they made such good clocks for determining location via the 24 hour/360 equivalency. *[ If you miss an noon observation one day you do not carry over the value to the next minute and second correction] The sidereal 3 min 56 sec are accumulative and have none of the cyclical aspects which reflect the orbital motion of the Earth that the Equation of Time has.What makes people freaks is that they attempt to justify the sidereal value astronomically when it is simply a convenient average of axial rotation over a 4 year calendrical year plus the leap day. I assure you the correct value for axial rotation through 360 degrees is 24 hours exactly,not one fraction more or less.If you can't manage that there is little point in attempting to see Newton's catastrophic maneuver that basically wiped out astronomy and lead to the exotic trash of the early 20th century. Simple stuff for an astronomer but you guys certainly need help with what the Equation of Time does and for that you need a sundialist.Leave out where the Equation of Time comes from (as that has been corrupted),only the association between 24 hour clocks and axial rotation wrt the Sun is necessary as a matter of conceptual safe mode. This is my final posting,truly. |
#66
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#67
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wrote:
only the association between 24 hour clocks and axial rotation wrt the Sun is necessary as a matter of conceptual safe mode. Agreed - but not with axial motion wrt 360 degrees - for that you need to subtract some 4 minutes from clock time, even if the clock was Harrison's. Cheers Martin -- Martin Frey http://www.hadastro.org.uk N 51 02 E 0 47 |
#68
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Dear Geraldine
Explain sidereal clocks, their timekeeping, their purpose, telescope setting circles and transit telescopes. Chris.B |
#69
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Tim Auton wrote: wrote: This final posting is for a true Englishman - John Harrison.His timekeeper for longitude is based on axial rotation of the Earth through 360 degrees in 24 hours even though a hybrid version was developed later based on stellar circumpolar navigation.The answer is before you as you look at a clock on the wall and even though digital clocks are common,people still love the way a clock keeps cyclical pace with the day through the motion of the Earth. It is true that scientists managed to bury the 24hour/360 deg equivalency but most people feel uncomfortable with the alternative value and with good reason,it is wrong. The thing IT IS TRIVIAL TO PROVE THAT IT IS NOT WRONG. Look at distant object (a star, galaxy, quasar - whatever the most distant object you can manage with your equipment) one night. Next night, see how long it takes for that object to return to the same point in the sky. It takes on sidereal day. Do this with many objects, just in case some are moving significantly. It takes one sidereal day. It takes that long because the Earth has completed one whole rotation about its axis RELATIVE TO THOSE OBJECTS, so you're looking at the same part of the sky (you chose a distant object to minimise parallax effects as the Earth also moves around the sun, the sun moves around the galactic centre etc. etc.). Looking at the same point means you have rotated through a full circle, which is defined to be 360 degrees. Therefore the Earth rotates 360 degrees in one sidereal day. QED. Tim -- This is not my helicopter. Another useless **** who thinks the Earth is spinning on its axis and doing nothing else. You ****ing freaks continue to believe the astronomical justification for the sidereal value and that makes you the dumbest people ever to set foot on the planet. You are so ****ing dull and conformist that children will have no chance to enjoy the insights of Kepler and Copernicus while you **** down their throats with warped space,time travel and all the other exotic sci-fi trash,trash that is built on that single obvious error by Flamsteed. |
#70
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Dear Geraldine
Explain sidereal clocks, their timekeeping, their purpose, telescope setting circles and transit telescopes. Chris.B |
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