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Q: solar system ( Answered 4 out of 5 stars,   1 Comment )
Subject: solar system
Category: Science > Astronomy
Asked by: karshish-ga
List Price: $5.00
Posted: 28 Apr 2004 04:12 PDT
Expires: 28 May 2004 04:12 PDT
Question ID: 337524
It is said by Plutarch and others that Aristarchus of Samos proposed a
modern, heliocentric model of the solar system in about 350 BC. It is
also claimed that Copernicus had access to Aristarchus's papers so his
theory may have been taken without attribution from the Pythagorean.
Any comments?

Request for Question Clarification by mathtalk-ga on 28 Apr 2004 07:49 PDT
Hi, karshish-ga:

Are you interested only in Comments, or is there a specific Question
to be Answered?  For example, would links to some scholarly evaluation
of the theory proposed by Aristarchus and its influence on Copernicus
be of interest?

regards, mathtalk-ga

Clarification of Question by karshish-ga on 28 Apr 2004 17:01 PDT
Hi mathtalk-ga

Yes, a reference to a scholarly evaluation of the relationship (if
any) between Aristarchus's putative theory ? because, as I understand
it, we only have secondary sources that confirm he proposed a
heliocentric model ? and Copernicus's Concerning the Revolutions?
would be very interesting. My interest in this topic was reignited
recently when I reread Koestler's The Sleepwalkers. Although I have
great respect for the late Arthur Koestler, my training as a scientist
makes me wary of accepting a popular writer's thesis, however erudite
the author.

I suppose my question is, what is the evidence to support the claim
that Aristarchus beat Copernicus by about 1800 years?
Subject: Re: solar system
Answered By: mathtalk-ga on 28 Apr 2004 19:42 PDT
Rated:4 out of 5 stars
Hi, karshish-ga:

Let me point you first to a student paper:

[Aristarchus of Samos, by Kristen Riley]

which pulls together some nice links from a classics perspective.

First note the image she's posted of a manuscript page from
Copernicus's own heliocentric treatise, De revolutionibus caelestibus:

in which a passage, struck out prior to publication, says (in translation):

"Philolaus believed in the mobility of the earth, and some even say
that Aristarchus of Samos was of that opinion."

Copernicus's reasons for leaving this out in the published version of
his work will have to remain something of an unexplored by-path for

Let's turn to the crux of your question, namely what grounds there are
for believing that Aristarchus (c. 310-230BC) proposed, not only that
the Earth moved, but that it moved in a circular orbit around the Sun.

It is true that a direct statement of this theory does not appear in
the one "surviving" work attributed to Aristarchus, On the Sizes and
Distances of the Sun and Moon.  However as often happens with those
whose ideas found justification long after they lived, very convincing
evidence for those ideas is conveyed by the contemporaneous
disagreements that survive.

Such is the case here with Archimedes citation of Aristarchus.  As Ms.
Riley has translated for us:

[Sand Reckoner, Chapter 1 by Archimedes]

"Now you are aware that 'universe' is the name given by most
astronomers to the sphere the center of which is the center of the
earth, and the radius of which is equal to the straight line between
the center of the sun and the center of the earth; this you have seen
in the treatises written by astronomers. But Aristarchus of Samos
brought out writings consisting of certain hypotheses, in which it
appears, as a consequence of the assumptions just made, that the
universe is many times greater than the "universe" just mentioned. His
hypotheses are that the fixed stars and the sun remain unmoved, that
the earth revolves about the sun in the circumference of a circle, the
sun lying in the middle of the orbit, and that the sphere of the fixed
stars, situated about the same center as the sun, is so great that the
circle in which he supposes the earth to revolve bears such a
proportion to the distance of the fixed stars as the center of the
sphere bears to its surface."

It should be said that Archimedes goes on to reject this theory, and
that his tone though polite is one of equable disparagement.

Others were more vociferous in condemning the theory on what might be
described as religious or philosophical grounds.  For example,
according a passage in Plutarch translated here:

[Plutarch, De facie in orbe lunae , c. 6]

there was a Stoic philosopher who wanted Aristarchus tried:

"Only do not, my good fellow, enter an action against me for impiety
in the style of Cleanthes, who thought it was the duty of the Greeks
to indict Aristarchus of Samos on the charge of impiety for putting in
motion the Hearth of the Universe, this being the effect of his
attempt to save the phenomena by supposing the heaven to remain at
rest and the earth to revolve in an oblique circle, while it rotates,
at the same time, about its own axis."

In addition a quotation preserved in the writings of Theon of Symrna
attributed to Dercyllides (or Dercylidas, apparently mentioned by
Xenophon as a contemporary of Plato), who:

"says that we must suppose the earth, the Hearth of the House of the
Gods according to Plato, to remain fixed, and the planets with the
whole embracing heaven to move, and rejects with abhorrence the view
of those who have brought to rest the things which move and set in
motion the things which by their nature and position are unmoved, such
a supposition being contrary to the hypotheses of mathematics."

This opposition to a heliocentric model demonstrates at a minimum some
currency in philosophical circles of the time, if not the precise debt
to Aristarchus.

Finally we may indulge ourselves in a slight speculation about the
relationship between the heliocentric theory and the one surviving
work by Aristarchus.  His calculations, which had a sound theoretical
basis though not free of measurement errors, showed the universe is
much bigger than his contemporaries contemplated, as Archimedes
prominently mentions.  They also showed that because of its distance,
the Sun was really much bigger than the Earth or the Moon.  It seems
that the notion of the Earth moving around the Sun may have been
motivated in part by the apprehension of how very much larger the Sun
is than the Earth.

regards, mathtalk-ga

Search Strategy

Keywords: Aristarchus Samos heliocentric Copernicus
karshish-ga rated this answer:4 out of 5 stars
sorry, I had overlooked rating this answer. The student paper was
something I did not know.

Subject: Re: solar system
From: pugwashjw-ga on 28 Apr 2004 05:53 PDT
In the Bible, the book of Job, written by Moses in the wilderness,
1473 B.C.E. Chapter 25, verses 7 & 10.....[7]hanging the earth on
nothing.... A DESCRIPTION OF THE EARTH FROM SPACE ????? [10]A circle
upon the face of the waters...THE MOONS SHADOW CROSSING THE EARTH
The book of Isaiah, written by Isaiah , in Jerusalem in 732 B.C.E.
Chapter 40 verse 22...There is one who is dwelling above the circle of
the earth, the dwellers in which are as grasshoppers...SOMEONE LOOKING
These facts were in evidence over 300 years before the said Plutarch
and Aristarchus. They has access to the writings of the Hebrews [
Israelites] holy scriptures, the TRUTH about our world, and how to
live in it, health matters etc. Otherwise known as the Old Testament.
Given to Moses and other Bible writers under DIVINE inspiration. God
made it all and explained it all, but only to the extent that the
people of the time could understand. Thes days we regard ourselves as
much more knowledgeable and sophisticated and require our explanations
to be more exact. But a round world is still a round world, even
though the ocean "looks" flat.

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