“In fact, the thickness of the Earth's atmosphere, compared with the size of the Earth, is in about the same ratio as the thickness of a coat of shellac on a schoolroom globe is to the diameter of the globe. That's the air that nurtures us and almost all other life on Earth, that protects us from deadly ultraviolet light from the sun, that through the greenhouse effect brings the surface temperature above the freezing point. (Without the greenhouse effect, the entire Earth would plunge below the freezing point of water and we'd all be dead.) Now that atmosphere, so thin and fragile, is under assault by our technology. We are pumping all kinds of stuff into it. You know about the concern that chlorofluorocarbons are depleting the ozone layer; and that carbon dioxide and methane and other greenhouse gases are producing global warming, a steady trend amidst fluctuations produced by volcanic eruptions and other sources. Who knows what other challenges we are posing to this vulnerable layer of air that we haven't been wise enough to foresee?”

— Carl Sagan

In Wonder and Skepticism, Skeptical Enquirer (Jan-Feb 1995), 19, No. 1.

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Carl Sagan 365

American astrophysicist, cosmologist, author and science ed… 1934–1996

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“We are now in a position to prove the following propositions : —
1. The distance of the sun from the earth is greater than eighteen times, but less than twenty times, the distance of the moon (from the earth); this follows from the hypothesis about the halved moon.
2. The diameter of the sun has the same ratio (as aforesaid) to the diameter of the moon.
3. The diameter of the sun has to the diameter of the earth a ratio greater than that which 19 has to 3, but less than that which 43 has to 6; this follows from the ratio thus discovered between the distances, the hypothesis about the shadow, and the hypothesis that the moon subtends one fifteenth part of a sign of the zodiac.”

Aristarchus of Samos ancient Greek astronomer and mathematician

p, 125
On the Sizes and Distances of the Sun and the Moon (c. 250 BC)

“Those who are skeptical about carbon dioxide greenhouse warming might profitably note the massive greenhouse effect on Venus. No one proposes that Venus's greenhouse effect derives from imprudent Venusians who burned too much coal, drove fuel-inefficient autos, and cut down their forests. My point is different. The climatological history of our planetary neighbor, an otherwise Earthlike planet on which the surface became hot enough to melt tin or lead, is worth considering — especially by those who say that the increasing greenhouse effect on Earth will be self-correcting, that we don't really have to worry about it, or (you can see this in the publications of some groups that call themselves conservative) that the greenhouse effect is a "hoax."”

Carl Sagan book Pale Blue Dot

Source: Pale Blue Dot: A Vision of the Human Future in Space (1994), p. 227

“It is impossible by means of inanimate material agency, to derive mechanical effect from any portion of matter by cooling it below the temperature of the coldest of the surrounding objects. [Footnote: ] If this axiom be denied for all temperatures, it would have to be admitted that a self-acting machine might be set to work and produce mechanical effect by cooling the sea or earth, with no limit but the total loss of heat from the earth and sea, or in reality, from the whole material world.”

William Thomson (1824–1907) British physicist and engineer

Mathematical and Physical Papers, Vol.1 http://books.google.com/books?id=nWMSAAAAIAAJ p. 179 (1882) "On the Dynamical Theory of Heat with Numerical Results Deduced from Mr Joule's Equivalent of a Thermal Unit and M. Regnault's Observations on Steam" originally from Transactions of the Royal Society of Edinburgh, March, 1851 and Philosophical Magazine iv, 1852
Thermodynamics quotes

“Mars has global warming, but without a greenhouse and without the participation of Martians. These parallel global warmings -- observed simultaneously on Mars and on Earth -- can only be a straightline consequence of the effect of the one same factor: a long-time change in solar irradiance.”

Khabibullo Abdusamatov (1940) Russian astrophysicist

as quoted by Lawrence Solomon in Look to Mars for the truth on global warming http://www.canada.com/nationalpost/story.html?id=edae9952-3c3e-47ba-913f-7359a5c7f723&k=0/, National Post, January 26, 2007.

“It would let me protect the Earth from asteroids. In fact, for a small fee I would protect the Earth on a monthly basis, locating rocks that could be steered into the Earth and then not doing it if the cheque didn't bounce.
We could finally commodify sunlight. A large solar collector at the Earth Sun L1 would block all the light that otherwise falls on the unworthy and could be sold to those that deserve it (Litmus test is the same as with Operation Nice Planet You Have, Shame If Anything Were To Happen To It).”

James Nicoll (1961) Canadian fiction reviewer

Livejournal comment http://james-nicoll.livejournal.com/226271.html?thread=2139359#t2139359
2000s

“Proposition 15. The diameter of the sun has, to the diameter of the earth a ratio greater than that which 19 has to 3, but less than that which 43 has to 6.”

Aristarchus of Samos ancient Greek astronomer and mathematician

p, 125
On the Sizes and Distances of the Sun and the Moon (c. 250 BC)
Variant: Proposition 10. The sun has to the moon a ratio greater than that which 5832 has to 1, but less than that which 8000 has to 1.

“The floating of the planets in the weightless air is due to the inner constitution of the globes, and the modernized drilling of the earth to exploit oil from within is a sort of disturbance by the modern demons and can result in a greatly harmful reaction to the floating condition of the earth.”

A.C. Bhaktivedanta Swami Prabhupada (1896–1977) Indian guru

Srimad Bhagavatam, Bhaktivedanta Book Trust, 1999. Canto 2, Chapter 7, verse 1, purport. Vedabase http://www.vedabase.com/en/sb/2/7/1
Quotes from Books: Loving God, Quotes from Books: Regression of Science

“If we suppose the distance of the fixed stars from the sun to be so great that the diameter of the earth's orbit viewed from them would not subtend a sensible angle, or which amounts to the same, that their annual parallax is quite insensible; it will then follow that a line drawn from the earth in any part of its orbit to a fixed star, will always, as to sense, make the same angle with the plane of the ecliptic, and the place of the star, as seen from the earth, would be the same as seen from the sun placed in the focus of the ellipsis described by the earth in its annual revolution, which place may therefore be called its true or real place.
But if we further suppose that the velocity of the earth in its orbit bears any sensible proportion to the velocity with which light is propagated, it will thence follow that the fixed stars (though removed too far off to be subject to a parallax on account of distance) will nevertheless be liable to an aberration, or a kind of parallax, on account of the relative velocity between light and the earth in its annual motion.
For if we conceive, as before, the true place of any star to be that in which it would appear viewed from the sun, the visible place to a spectator moving along with the earth, will be always different from its true, the star perpetually appearing out of its true place more or less, according as the velocity of the earth in its orbit is greater or less; so that when the earth is in its perihelion, the star will appear farthest distant from its true place, and nearest to it when the earth is in its aphelion; and the apparent distance in the former case will be to that in the latter in the reciprocal proportion of the distances of the earth in its perihelion and its aphelion. When the earth is in any other part of its orbit, its velocity being always in the reciprocal proportion of the perpendicular let fall from the sun to the tangent of the ellipse at that point where the earth is, or in the direct proportion of the perpendicular let fall upon the same tangent from the other focus, it thence follows that the apparent distance of a star from its true place, will be always as the perpendicular let fall from the upper focus upon the tangent of the ellipse. And hence it will be found likewise, that (supposing a plane passing through the star parallel to the earth's orbit) the locus or visible place of the star on that plane will always be in the circumference of a circle, its true place being in that diameter of it which is parallel to the shorter axis of the earth's orbit, in a point that divides that diameter into two parts, bearing the same proportion to each other, as the greatest and least distances of the earth from the sun.”

James Bradley (1693–1762) English astronomer; Astronomer Royal

Miscellaneous Works and Correspondence (1832), Demonstration of the Rules relating to the Apparent Motion of the Fixed Stars upon account of the Motion of Light.

“As I came through the desert thus it was,
As I came through the desert: All was black,
In heaven no single star, on earth no track;
A brooding hush without a stir or note;
The air so thick it clotted in my throat.”

James Thomson (B.V.) (1834–1882) Scottish writer (1834-1882)

Part VI
The City of Dreadful Night (1870–74)

“Not only was there a layer of ice above the atmosphere, the Bible teaches that the earth also had a layer of water UNDER the crust of the earth. The earth’s crust today is about 10-25 miles thick. Many who have studied this topic agree that the earth had huge reservoirs of water maybe ten miles down, when the earth was first created. Psalm 24:1-2, “The earth is the Lord’s and the fullness thereof; the world, and they that dwell therein. For He hath founded it UPON the seas, and established it UPON the floods..””

Kent Hovind (1953) American young Earth creationist

Was the earth founded on the water? Psalm 136:6 tells us that God “stretched out the earth ABOVE the waters.”
Source: What On Earth Is About To Happen… For Heaven’s Sake? (2013), p. 46

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Carl Sagan 365

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