Revelation: Planets are not stars

Greetings.

Who first discovered that planets were planets and not simply wandering
stars? To the ancients, it must have seemed that the planets were simply
very large, bright stars which traversed a fixed path across the sky. Who
first came up with the idea that they might actually be far-away
Earth-sized rocks which one could conceivably visit, and which might
support life of their own? And who was the first person to actually prove
this theory?

Regards,
Tristan

--
_
_V.-o Tristan Miller [en,(fr,de,ia)] Space is limited
/ |`-' -=-=-=-=-=-=-=-=-=-=-=-=-=-=-= In a haiku, so it's hard
(7_\\ http://www.nothingisreal.com/ To finish what you

Regards,
Tristan

Dad?

_V.-o Tristan Miller [en,(fr,de,ia)] Space is limited
/ |`-' -=-=-=-=-=-=-=-=-=-=-=-=-=-=-= In a haiku, so it's hard
(7_\\ http://www.nothingisreal.com/ To finish what you BRBR

....began?
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Tristan Miller wrote:
Greetings.

Who first discovered that planets were planets and not simply wandering
stars? To the ancients, it must have seemed that the planets were simply
very large, bright stars which traversed a fixed path across the sky. Who
first came up with the idea that they might actually be far-away
Earth-sized rocks which one could conceivably visit, and which might
support life of their own?


And who was the first person to actually prove
this theory?

Neil Armstrong, at least for the moon.


Regards,
Tristan



--
Maurice Barnhill
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Department of Physics and Astronomy
University of Delaware
Newark, DE 19716

"Tristan Miller" wrote in message
...
Greetings.

Who first discovered that planets were planets and not simply wandering
stars? To the ancients, it must have seemed that the planets were simply
very large, bright stars which traversed a fixed path across the sky. Who
first came up with the idea that they might actually be far-away
Earth-sized rocks which one could conceivably visit, and which might
support life of their own? And who was the first person to actually prove
this theory?


According to
http://imagine.gsfc.nasa.gov/docs/as...s/980215e.html :

"The consideration of stars and planets as physical objects that obey
knowable laws started in the Middle East (and somewhat in China) and has
spread into cultures that are the intellectual heirs of the Greeks. A fairly
modern view of the heavens only started in the early 1600's when Galileo
first turned the newly invented telescope to the heavens and saw worlds in
their own right. With the Newtonian revolution in physics, it was realized
that stars were just Suns, and all obeyed the same Laws of Physics as hold
here on the Earth."

I don't know who prior to Galileo posited this notion. It may have required
Galileo's telescope to "prove" the theory.

The moon is a simpler question. Do you think that it was obvious early on
that that was some sort of big ball of rock up there?

The planets of course don't twinkle like stars. I don't know if any ancient
used that fact to hypothesize that the planets were much closer than the
stars to us.

M C Hamster "Big Wheel Keep on Turnin'" -- Creedence Clearwater Revival

Tristan Miller wrote in
:

Greetings.

Who first discovered that planets were planets and not simply
wandering stars? To the ancients, it must have seemed that the
planets were simply very large, bright stars which traversed a fixed
path across the sky. Who first came up with the idea that they might
actually be far-away Earth-sized rocks which one could conceivably
visit, and which might support life of their own? And who was the
first person to actually prove this theory?

Galileo. Without a telescope, they do look like bright wandering stars.

On Thu, 07 Oct 2004 18:46:00 GMT, Paul Lawler
wrote:

Tristan Miller wrote in
:

Who first discovered that planets were planets and not simply
wandering stars?

Galileo. Without a telescope, they do look like bright wandering stars.
Just like Venus, only smaller.
--
Crashj

Tristan Miller wrote, in :

Greetings.

Who first discovered that planets were planets and not simply wandering
stars? To the ancients, it must have seemed that the planets were simply
very large, bright stars which traversed a fixed path across the sky. Who
first came up with the idea that they might actually be far-away
Earth-sized rocks which one could conceivably visit, and which might
support life of their own? And who was the first person to actually prove
this theory?

Copernicus proposed the theory and Kepler gave a rationale for their periods
of revolution, Newton's theory of Gravitation gave the mechanism to explain
Kepler.
--
Nick Spalding

M C Hamster wrote:

(snip)

"The consideration of stars and planets as physical objects that obey
knowable laws started in the Middle East (and somewhat in China) and has
spread into cultures that are the intellectual heirs of the Greeks. A fairly
modern view of the heavens only started in the early 1600's when Galileo
first turned the newly invented telescope to the heavens and saw worlds in
their own right. With the Newtonian revolution in physics, it was realized
that stars were just Suns, and all obeyed the same Laws of Physics as hold
here on the Earth."

I don't know who prior to Galileo posited this notion. It may have required
Galileo's telescope to "prove" the theory.

Copernicus had posited a heliocentric model for the solar system.
Kepler's laws of planetary motion had found that the sun, not
the earth, was at one of the foci of the ellipse of the planet's
orbit, making Copernicus's model clearly the most parsimonious
one. Galileo's observations, however, were the first direct
evidence that the planets were physically different from the
stars, since through the telescope he could resolve them as disks
(or, in the case of Saturn, as a strange "eared" object) whereas
he could not with the stars.

The moon is a simpler question. Do you think that it was obvious early on
that that was some sort of big ball of rock up there?

I think in general not. It was only with a telescope that one
could determine that there were mountains on the moon, so prior
to that it was simply an oddly splotched object. Further, if my
memory is correct, I think the Greeks had underestimated the
distance to the moon by a factor of about 10, making their belief
about the moon's size off by that factor as well.

The planets of course don't twinkle like stars. I don't know if any ancient
used that fact to hypothesize that the planets were much closer than the
stars to us.

Actually, contrary to common belief, the planets *do* twinkle.
One of the most common celestial objects mistaken for a UFO is
the planet Venus when seen close to the horizon where its
twinkling is most noticeable. The planets may seem to twinkle
less, but that's primarily due to their brightness which makes
the variation in its brightness as it twinkles less noticeable
than it is for the stars.

Finally, on an unrelated final note, the Greeks considered the
sun and moon as planets as well, as they classified all of the
objects that wandered the celestial sphere as planets or
"wanderers." So they had certainly recognized that at least some
of their planets were of a different nature from the stars.

M C Hamster "Big Wheel Keep on Turnin'" -- Creedence Clearwater Revival

--
Mark Thornquist

M C Hamster "Big Wheel Keep on Turnin'" --

Kewl tune!

_______
Blog, or dog? Who knows. But if you see my lost pup, please ping me!
A
HREF="http://journals.aol.com/virginiaz/DreamingofLeonardo"http://journal
s.aol.com/virginiaz/DreamingofLeonardo/A

I don't think it says that in Revelations.


--
Russell Stewart | E-Mail:
UNM CS Department | WWW: http://www.swcp.com/~diamond

"Stop saying the cause of Rick James' death is a 'mystery'"
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