January 6, 2006

Astronomical distances, and the death of young earth creationism

In a discussion forum I sometimes participate in, former young earth creationist Glenn Morton recently clued me in to a recent astronomy article about the determination of the distance of one of our Milky Way galaxy's spiral arms from the Earth.

Here is the article reference:

"The Distance to the Perseus Spiral Arm in the Milky Way"
(Science magazine, December 8, 2005)
by Y. Xu, M. J. Reid, X. W. Zheng, and K. M. Menten

The scientists state:

We have measured the distance to the massive star-forming region W3OH in the Perseus spiral arm of the Milky Way to be 1.95 ± 0.04 kiloparsecs (5.86 x 1016 km). This distance was determined by triangulation, with the Earth's orbit as one segment of a triangle, using the Very Long Baseline Array.

1.95 kiloparsecs is about 6,360 light-years, so what this means is that we're observing this location right here in our own galaxy (let alone all of the other billions of galaxies in our universe) from about 6,360 years ago.

Glenn writes:

This measurement has an error of 40 parsecs (130 lightyears), or 2% of the distance. This means, that the [spiral arm] lies between 6,226 and 6,487 light-years distance. The error is so small that there is no way that this very close [spiral arm] can fit within the 6,000 year universe of the YECs.

Here you can see a nice map of our Milky Way galaxy showing the relative positions of the Earth and the Perseus spiral arm:

The Universe within 50000 Light Years: The Milky Way Galaxy

This is just another example of the fact that right within our own galaxy, we're observing even relatively nearby parts of our galaxy from a time in the past BEFORE young earth creationists say that the Universe existed, thus proving that young earth creationism is false, and showing why young earth creationism is just as obsolete as geocentrism.

Just so everyone is aware of this, there are other geometric methods used to determine interstellar and intergalactic distances (i.e., they don't depend on magnitude measurements of Cepheids or other kinds of cyclically pulsating stars). They just don't happen to be the particular parallax method using the Earth's orbit as the triangle baseline, but the baseline is "in reverse" being at the location of what is being observed. Here are three examples of this, one in our galaxy, one in a neighbor galaxy (Large Magellanic Cloud), and one in a galaxy that's part of another galaxy cluster:

Star V838 Monocerotis
(about 20,000 light-years from Earth)

Supernova 1987A
(about 168,000 light-years from Earth)

"A 4% geometric distance to the galaxy NGC4258 from orbital motions in a nuclear gas disk"
(about 23,500,000 light-years from Earth)

Of course, according to young earth creationist rhetoric, astronomical science is really just a form of atheistic evolution, and astronomers are nothing more than evolutionists engaging in the worldwide evolutionist conspiracy.

Hmmm... I hope I don't lose my secret decoder ring!




Unsettling this settled dogma came Galileo and his telescope, a mere decade after Giordano Bruno (1548?-1600) was murdered by the Church in the flames of Campo dei Fiori -- for unorthodox opinions. In his Sidereus Nuncius or Starry Messenger (1610) Galileo announced his support for the Copernican view of the universe: the earth moving around the sun, and Jupiter circled by moons.

Blasphemy! cried the clerics. Not at all, replied the scientist. Look here and see for yourselves. It is impious to look, said some; these so-called moons are delusions of the devil, said others. Jesuit Father Christoph Clavius ingeniously argued that "to see satellites of Jupiter men had to make an instrument which would create them." Such a discovery contradicted the prescribed number of bodies in the heavens. Galileo counter-argued that a figurative interpretation of the biblical statements would save his observations from the taint of heresy. He wrote as much to his friends, Father Benedetto Castelli and the Grand-Duchess Christina -- but to no avail.

Father Tomasso Caccini, a Dominican, preached a sermon against him grounded in a tasteless pun (after Acts 1:11) on the scientist's name: "Ye men of Galilee, why stand ye looking into heaven?." Galileo had said, "[The universe] cannot be read until we have learnt the language and become familiar with the characters in which it is written. It is written in mathematical language, and the letters are triangles, circles and other geometrical figures, without which means it is humanly impossible to comprehend a single word," (Opere Il Saggiatore) so, not content with reviling astronomers, Caccini assured his flock that "geometry is of the devil" and that "mathematicians should be banished as the author of all heresies."

The Archbishop of Florence called his discoveries unscriptural. A Father Lacazre claimed Galileo's researches cast "suspicion on the doctrine of the incarnation." The word in clerical circles was that such a cosmology "upsets the whole basis of theology. If the earth is a planet, and only one among several planets, it cannot be that any such great things have been done especially for it as the great doctrine teaches. If there are other planets, since God makes nothing in vain, they must be inhabited; but how can their inhabitants be descended from Adam? How can they trace back their origin to Noah's Ark? How can they be redeemed by the Saviour?" And, not surprisingly, one cleric, the Dominican Father Nicolò Lorini called Galileo's discoveries "atheistic."

From: The War on Galileo
by Ronald Bruce Meyer

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