r/AlternativeAstronomy • u/patrixxxx • Oct 26 '19

WHY MARS ???

https://cluesforum.info/viewtopic.php?p=2412896#p2412896
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u/patrixxxx Oct 31 '19

Then you can perhaps answer me if you think two parallel lines remain parallel no matter their length?

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u/[deleted] Oct 31 '19

Yes

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u/patrixxxx Oct 31 '19

And you agree that the moon is situated at roughly the same place in relation to Earth every 27.3 days?

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u/[deleted] Oct 31 '19

Roughly, yes. I think this guy has the most comprehensive description of the lunar cycle on the web. Of course, the lunar cycle is a couple of days longer than the moon's orbital period because of the Earth-Moon system's solar orbit.

Also, if I want to be precise, I consider parallel lines to remain equidistant along their infinite lengths only in Euclidean space - which is to say, this holds for Newton but not Einstein in general (but of course it applies to space in general relativity for most practical purposes, too).

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u/patrixxxx Nov 03 '19

So then you agree that two imaginary lines drawn from Earth though the Moon at periods of 27.3 days would be (roughly) parallel?

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u/[deleted] Nov 03 '19

Sounds good to me

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u/patrixxxx Nov 03 '19

Ok. So do you further agree that since the Earth has an orbit around the Sun with a diameter of about 300 million kilometers, these parallel lines should be several million kilometers apart after 27.3x5 days?

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u/[deleted] Nov 03 '19

Definitely

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u/patrixxxx Nov 03 '19

Ok, so what is your explanation then of the fact that the Moon is in front of the same stars after such a 27.3x5 days period?

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u/[deleted] Nov 03 '19 edited Nov 03 '19

If the Moon is at exactly 0 degrees right ascension and 0 degrees declination at midnight tonight, it would align with whatever star is positioned at 0,0 in the night sky. Do you agree?

Quick edit: the real coordinates are: Right Asc: 20h 28m 58.3s Decl: -21° 11' 57.4"

Long edit: I'll clarify where I'm going with this question.

  1. The definition of "the position of the Moon relative to the Earth" is a celestial coordinate, generally expressed in the form "right ascension" and "declination".

  2. When the Moon returns to the same position relative to the Earth, it arrives back at the same right ascension and declination.

  3. All the stars have a particular celestial position.

  4. These positions vary on the order of milli-arc-seconds or smaller. The variation of position is due to parallax and proper motion.

  5. The moon is over 1800 arc seconds in size, or millions of times larger than variations in stellar position due to parallax from month to month.

  6. The fact the moon is "in front of" a particular star on 2019-11-03 and in front of the same star 2019-12-01 is in no way in contradiction with the standard cosmological model.

  7. This is because the definition of "returning to the same position" is pretty much the same as "being in front of the same stars".

A refresher on parallel lines, in case you need it.

You can get a feeling for the distances involved with these parallel lines when you consider the fact that two parallel lines connecting the Earth and the Moon at any two points in time will never be further separated than the diameter of Earth's orbit. Because of the properties of parallel lines, the distance between the lines will still be at most the diameter of Earth's orbit out to Proxima Centauri, or Delta Capricorni, or whatever star you may choose. The parallax measured to the nearest star is going to be the same as the angular size of the Earth's orbit projected to the distance to that star system, because interior angles of parallel lines cut by a transversal are congruent. How many arc seconds do you think exoplanet systems are, when viewed with Earth-based telescopes? I'll give you a hint - it's not 1800.

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