|
|
Thread Tools | Display Modes |
#21
|
|||
|
|||
Proof of the Earth's Rotundity
On Fri, 24 Oct 2014 20:54:37 +0100, "Lord Androcles"
wrote this crap: "Bill Owen" wrote in message ... On 10/23/14 12:43, Lord Androcles wrote: "Quadibloc" wrote in message ... You want astronomy to remain simply an inspirational pastime, with a "thus far and no further" to serious investigation of planetary motions. We would never have discovered Neptune listening to people like you. John Savard ================================================== ============= Funny, I don't recall seeing "Savard" as a co-discoverer of Neptune in any 1846 newspaper. Perhaps one need to be a pompous arsehole to belong to "we". Neptune would have been swept up by the Bonner Durchmusterung in the 1850s, although they might have mistaken it for a star. Certainly a comparison of the BD to the plates of the Astrographic Catalogue (difficult but not impossible in the 1890s) would have done the trick. In other words, its discovery would have been like that of Uranus. BTW, I can claim to be a co-discoverer of Neptune in a strange sort of way. A few years ago I took a few exposures of Neptune (and Triton) and submitted the astrometry to the Minor Planet Center along with all my other asteroid observations that night -- and the MPC gave Neptune a provisional designation! Gareth and I had a good chuckle about it, and then he went off and upgraded the software so it wouldn't happen again. -- Bill ================================================= === Why are planetary orbits so damned circular? We only know about the ones around our star. This signature is now the ultimate power in the universe |
#22
|
|||
|
|||
Proof of the Earth's Rotundity
On Friday, October 24, 2014 11:37:26 PM UTC+1, Mike Collins wrote:
http://mars.nasa.gov/allaboutmars/nightsky/retrograde/ NASA assume that people are able to interpret images. The animations shows Mars in the night sky from Gale Crater but to simplify the image they didn't include the Sun or other visible planets assuming that interested viewers would have the sense to realise this. The Earth from the surface of Mars and its motion around the Sun would contain roughly the same features as Venus seen from Earth with its increase in size and its phases as it emerges out from behind the central Sun,swings out to its widest point and then back in front of the Sun http://www.halien.com/TAS/Gallery/planet/Venus02.jpg http://artsandstars.ens-lyon.fr/venu...es.png?lang=en The trick is to account for the motion of the outer planet looking in towards the planet in an inner orbital circuit and that involves switching references to the motion of the background stars behind the Sun thereby setting up the central Sun as a reference point for the motion of the inner planet. Try giving the NASA animation of the Earth seen from Mars the familiar increase in size as the Earth approaches the orbit of Mars or its phases and let me know how you get on. |
#23
|
|||
|
|||
Proof of the Earth's Rotundity
On Saturday, October 25, 2014 3:17:29 AM UTC-6, oriel36 wrote:
The one thing missing was what input the Earth's motion has in these sequence of images as without the Earth's orbital motion, Venus would move through those phases quicker from a stationary observer rather than being on a moving Earth. Yes, that's correct, since the Earth orbits the Sun in the same direction as Venus, but (in angular terms) more slowly. In eight years, there are five conjunctions between Venus and the Sun from Earth's viewpoint, so the Earth catches up with Venus in its orbit five times. Thus, from Earth, Venus is seen to go through its phases five times, while a stationary observer would see it go through its phases thirteen times (5 + 8). John Savard |
#24
|
|||
|
|||
Proof of the Earth's Rotundity
On Saturday, October 25, 2014 11:54:44 AM UTC-7, Quadibloc wrote:
... In eight years, there are five conjunctions between Venus and the Sun from Earth's viewpoint, so the Earth catches up with Venus in its orbit five times. Thus, from Earth, Venus is seen to go through its phases five times, while a stationary observer would see it go through its phases thirteen times (5 + 8). John Savard Yes, and this graphic... http://www.lunarplanner.com/Images/V...et%20Paths.gif .... represents the path of Venus among the fixed stars over each of those 5 passages, the differences between them having to do with the position of Venus WRT the ecliptic, that is, if Venus is above the Sun or below the Sun or nearly even with the Sun as it arrives at inferior conjunction. Alas, poor Gerald has no chance to understand, since he cannot visualize perspectives, even if his life depended on it... which, fortunately for Gerald, it doesn't... |
#25
|
|||
|
|||
Proof of the Earth's Rotundity
On Saturday, October 25, 2014 8:48:59 PM UTC+1, palsing wrote:
On Saturday, October 25, 2014 11:54:44 AM UTC-7, Quadibloc wrote: ... In eight years, there are five conjunctions between Venus and the Sun from Earth's viewpoint, so the Earth catches up with Venus in its orbit five times. Thus, from Earth, Venus is seen to go through its phases five times, while a stationary observer would see it go through its phases thirteen times (5 + 8). John Savard Yes, and this graphic... http://www.lunarplanner.com/Images/V...et%20Paths.gif ... represents the path of Venus among the fixed stars over each of those 5 passages, the differences between them having to do with the position of Venus WRT the ecliptic, that is, if Venus is above the Sun or below the Sun or nearly even with the Sun as it arrives at inferior conjunction. Alas, poor Gerald has no chance to understand, since he cannot visualize perspectives, even if his life depended on it... which, fortunately for Gerald, it doesn't... What is encouraging is that people can put the increase in size of Venus and changes in phases as it approaches the Earth's orbit in context of its motion around the Sun so they should have no problem with the view of the Earth from Mars when its phases and increase in size will eventually be imaged.. http://www.farhorizons.nl/planets/Ve...007%20oost.jpg There is no need to throw good information after bad so that Owen at JPL has the responsibility of setting his colleagues straight on how the motion of the Earth around the Sun and against the background stars would look like from the surface of Mars using the known principles based on the motion of Venus as seen from the Earth. The input of the Earth's orbital motion into observations of the motion of the inner planets from the Earth's surface requires nimble reasoning as it requires a number of important modifications which chained older astronomers to observations which ultimately are counter-productive. The most notable modification is switching the reference for the Sun apparent motion through the background field of stars to the productive apparent motion of the background stars behind the central Sun thereby creating the background for appreciating the grandstand motion of the inner planets around the Sun. Here is the less productive view of the Sun's motion through the Zodiac by Huygens and its nonsensical extension via Newton " Here take notice, that the Sun or the Earth passes the 12 Zodiacal signs,or makes an entire revolution in the ecliptic in 365 days, 5 hours 49 min. or there about, and that those days, reckon'd from noon to noon, are of different lenghts; as is known to all that are vers'd in Astronomy" Huygens "That the fixed stars being at rest, the periodic times of the five primary planets, and (whether of the sun about the earth, or) of the earth about the sun, are in the sesquiplicate proportion of their mean distances from the sun." Newton Yes it is a tangle and yes most of it can be dealt with in a reasoned way so everyone can get a clear insight into where they stand without having to cut each other to pieces however,in the interim, people can appreciate the motion of Venus seen from Earth and safely predict what the motions of the Earth will look like from Mars. |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
A0(x) = PROOF(x) | [email protected] | Astronomy Misc | 0 | February 8th 12 12:46 AM |
Special Relativity proof Chapt9 Proof that Doppler shift isnonexistent in light-waves #46 Atom Totality theory 5th ed. | Archimedes Plutonium[_2_] | Astronomy Misc | 21 | October 13th 11 09:26 PM |
deuterium in Comets as proof of a 10 billion year old Earth? #183Atom Totality Theory | Archimedes Plutonium[_2_] | Astronomy Misc | 3 | November 26th 09 08:20 AM |
Debunked by Proof: Einstein's Relativity Theory Is Wrong! - PROOF #1 | qbit | Astronomy Misc | 6 | August 9th 07 04:04 PM |
proof Permian mass-extinction caused by SolarFlares Earth's AirConditioner | Archimedes Plutonium | Astronomy Misc | 2 | August 11th 03 07:37 AM |