MemberlistThe Library Index  FAQFAQ   SearchSearch   RegisterRegister   ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 
Eclipse (Astrophysics)
Reply to topic
View previous topic :: View next topic  
Ishmael


In: Toronto
View user's profile
Reply with quote

It has long bothered me that my work (which most of you do not know) has been unable to explain the cosmic "coincidence" of the Moon's size matching that of the Sun when seen from the Earth.

However... I had long suspected this apparent coincidence was nothing more than an illusion.

I am right.

The size of the Moon does not, in fact, match that of the Sun when both are viewed from the Earth. It turns out that the Moon is quite a bit smaller. Truth is, the Moon happens to fall within a very wide range of sizes that would produce apparent matches with the Sun's disk when viewed from the Earth.

These images taken from orbit establish my case.
Send private message
Chad


In: Ramsbottom
View user's profile
Reply with quote

It would be interesting to know at what distance from the Moon these pictures were taken. The Sun and Moon will of course appear exactly the same size when viewed from a particular given distance in space.

If you disregard the magnifying effect of various atmospheric conditions, you would expect the Moon to look smaller (when viewed from Earth) when it is on the horizon, than when it is overhead (because it is several thousand miles further away)... but the atmosphere does play tricks.

All that being said... the odds of a body the size of the Moon being placed in the sky at just the right distance to allow it to appear to have a similar diameter to a body the size of the Sun, must still be very, very large indeed.

Coincidence? I think the jury is still out.
Send private message
Ishmael


In: Toronto
View user's profile
Reply with quote

Maybe.

But if we assume it isn't coincidence, how in heck can we explain it?
Send private message
Mick Harper
Site Admin

In: London
View user's profile
Reply with quote

If it's of any interest, SCUM began life because Sirius is the same mass as the Sun and I asked the question, "What is the probability that from any given point in the universe, the two brightest stars on view shall be of the same mass?" Since the answer is zillions-to-one and yet we occupy such a position, it followed that Sirius had to be the Sun (the double image being produced by a nearby black hole slowing up one set of light rays).

It wasn't but by then it was too late and the universe had bared its most precious secrets to me.
Send private message
Chad


In: Ramsbottom
View user's profile
Reply with quote

So now we have two "when viewed from Earth" zillion to one coincidences, plus the "apsis-solstice" coincidence... that's three coincidences too many.

Coming back to the Sun-Moon apparent size coincidence... Given that in the distant past (if orthodoxy is correct about the Moon moving away from the Earth) the Moon would have appeared larger (and in the distant future it will appear smaller)... isn't it a rather strange coincidence that just at the very (and only) time that they both appear to be the same size, there just happens to be a sentient species around to notice it?

{Actually I don't believe the "apsis-solstice" thing is a coincidence... but that still leaves two.}
Send private message
Ishmael


In: Toronto
View user's profile
Reply with quote

Mick Harper wrote:
If it's of any interest, SCUM began life because Sirius is the same mass as the Sun and I asked the question, "What is the probability that from any given point in the universe, the two brightest stars on view shall be of the same mass?" Since the answer is zillions-to-one...


Sirius is composed of two stars. Sirius A is 2x as massive as the Sun and Sirius B is about the same mass as the Sun. However, Sirius B is a white dwarf and was (so they say) once the more massive of the two stars.

Of course, Sol used to be part of a binary pair as well, as some of you know. I'm willing to bet that the Sol binary and the Sirius Binary were once in orbit around one another -- and this is why they are of similar mass (though exactly why bodies tend to be paired up with similar masses I've yet to explain).

I'm also willing to bet that Sirius B is on its way to meeting the same fate as did Sol's lost companion. Just hope I'm here to collect in 100 million years or so.
Send private message
Chad


In: Ramsbottom
View user's profile
Reply with quote

Right... Well there's still one to go then.
Send private message
Buck Trawicky



View user's profile
Reply with quote

Greetings, from a Newby,
I am merely testing my access. Ignore me. (Though this is very important stuff.)
--Buck, in Wisconsin
Send private message Send e-mail
Display posts from previous:   
Reply to topic

Jump to:  
Page 1 of 1

MemberlistThe Library Index  FAQFAQ   SearchSearch   RegisterRegister   ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 


Powered by phpBB © 2001, 2005 phpBB Group