|And God said, “Let there be lights in the
expanse of the heavens to separate the day from the night. And let them
be for signs and for seasons, and for days and years."
think thy thoughts after thee, O God.
Timekeeping doesn't come automatically without effort and skill, and so this example is a prototype of how the silent speech of Psalm 19:4 works in practice.
The silent speech in astronomy declares God's glory and handiwork in greater and greater detail, as skilled craftsmen interpret the starry hosts as timekeepers. This skilled work goes on for centuries and millennia, and even continues today, always providing greater cause for awe and wonder, as each major advance in astronomy leads to further evidence for God's handiwork at timekeeping, and its unfolding shows an unending increase in marvelous and unexpected depth and complexity. [FOOTNOTE: In contrast to this, consider Ernst Haeckel's claim that the explanation of the spontaneous origin of life (another grand theme of God's Silent Speech) is "no more difficult to us than the explanation of the physical properties of inorganic bodies." History of Creation (1876), Vol I. p. 406. See also his Riddle of the Universe and commentary on it by Sir Oliver Lodge, Life and matter : a criticism of Professor Haeckel's "Riddle of the Universe" (1907). Haeckel fell into the trap of assuming that the current understanding of science is final and authoritative.]
Lascaux Cave Painting from the
Chamber of Bulls, Lascaux Cave (17,000 BC)
Identification of Pleiades, Taurus and Orion's Belt
The insets show the actual star configurations.
The stars to the right of Aldebaran are, in counterclockwise order
theta tauri, gamma tauri, delta tauri and epsilon tauri (all red giants)
Star map showing the Taurus Constellation
with Pleiades and Orion's belt
Star map showing
Pleiades, Aldeberan and Orion's belt
Lascaux Hall of Bulls Panorama
The bull of Figures 1-3 is on the ceiling partially visible at the upper right
Photograph reproduced by courtesy of Musée de Périgord, Periguex, France
The Egyptian Sky goddess Nut and the Earth god Shu
depicted in many burial chambers and coffins
The Ecliptic showing Pleiades, Taurus and Orion
Precession of the Equinoxes
4000 BC to 2000 AD
Motion of Stars near the Big Dipper
Ptolemaic System of epicycles.
Click on the image for animation.
[FOOTNOTE: If the animation doesn't work note that Java is required. Go to the Wikipedia article on epicycles and click on the "Java simulation of the Ptolemaic System" under the heading "Animated Simulations" at the bottom of the page. The simulation is from at Paul Stoddard's Animated Virtual Planetarium, Northern Illinois University.]
Copernicus' Solar System
from De Revolutionibus Orbium Coelestium (1543)
First Book, Folio 9 Verso
This diagram does not show the epicycles that
Copernicus used to adjust for the apparent speed change over an orbit.
The Zodiac is the band in which the Sun and Planets move over the course of the year. The journey of the Sun through this band of stars passes succesively through the signs (constellations) of the zodiac along a path called the ecliptic. A sidereal year is the time required for the Sun to complete the circuit through the Zodiac. At the vernal equinox (around March 21), the length of the day equals the length of the night. This is the beginning of the Jewish religious calendar. The Jewish secular calendar begins at the autumnal equinox (around September 21).
There is indirect, but plausible, evidence that the Babylonian (Sumerian) Zodiac was first formulated at the time when the Sun was located in the Pleiades (see the figure below) during the Vernal equinox.
This occurred around 2300 BC. The Pleiades are called in Sumerian "MUL.MUL" or the "star of stars" and stands at the head of their Zodiac, so it is reasonable to infer that the zodiac was established around that time.
It is interesting that the book of Job 38:31-32 mentions three constellations: Orion, Pleiades, and The Bear. The Bear, of course, marks the North Star. Pleiades and Orion are in the Sumerian Zodiac, with Pleiades in the prominent position. This fact may indicate that Job, as well as the Sumerian Zodiac date to around 2,000-2,500 BC. By the time of the Babylonian Zodiac (around 500 BC), the Earth's precession has put Aries, which heads the Babylonian Zodiac, in the principal position, and both Pleiades and Orion are omitted from the Zodiac. The twelve signs of the Babylonian zodiac are still used today.
Astrologers use the Babylonian zodiac, without adjustment for the earth's precession. This is called the tropical zodiac and is headed by Aries, which is associated with March 21-April 20. The sidereal zodiac follows the earth's precession. By the turn of the calendar in 1 AD the equinox entered the Pisces constellation, and currently (2,000 AD) the equinox is at the trailing edge of Pisces and moving towards Aquarius.
The following illustration shows the sidereal zodiac with the 2010 calendar. The Vernal equinox occurs on March 20.
The following is another depiction of the Ecliptic and the location of the Vernal Equinox between 4000 BC and 2500 AD.
Date of Jesus' Crucifixion
One consequence of the extreme precision of astronomical calculations is that it is possible to determine with good precision the exact appearance of the heavens at any particular date. The maximum positional error for the solar system and fixed stars between 2,000 BC and 2,000 AD is about 20 seconds in time and a few arc-seconds in position. Readily available astronomy programs, such as Starry Night, can compute positions and movements for any time in this range on a home computer, with a variety of display options.
Frederick A. Larson used astronomy software to investigate the events surrounding Jesus' birth and death. The documentary dvd Bethlehem Star presents the conclusions that he came to in this investigation. I found the discussion of Jesus' crucifixion to be particularly interesting. Larson (with others) argues that there was a lunar eclipse on the day of Jesus' crucifixion based on the reference to a "blood moon" in Acts 2:20, and that the crucifixion occurred on a Friday that was also the time of the Jewish Passover celebration. This leads to the conclusion that Jesus' Crucifixion occurred on April 3, 33 AD, a date that is arrived at by a number of lines of argument, from the time of Isaac Newton to the present -- see the Wikipedia article on the Crucifixion of Jesus. Astronomy programs confirm that a lunar eclipse occurred on this date at about 3 PM and that it was visible in Jerusalem for about 30 minutes after sunset. Larson also notes that on this date, at the time of the eclipse, the Sun was located in Aries, in the vicinity of the constellation's heart (or liver?), and draws some interesting conclusions from this.
The following is the calendar for 33 AD. The Vernal equinox fell on March 20, and the crucifixion was on Friday, April 3, just before passover celebration on that year, that same evening. There was a lunar eclipse at 3 PM that afternoon, the end of which was visible at Jerusalem for about 30 minutes after Sunset, and appeared as a "blood moon" mentioned by the Apostle Peter in Acts 2:20. On this date the Sun was in or near the heart of Aries.
1, The width of the Moon is about 29.5 to 33.5 arc-minutes. The width of the Sun is about 31.6 to 32.7 arc-minutes. During a full solar eclipse the Sun's corona is visible over the entire perimeter. It remains complete for only a few seconds.
2. Earth's rotation will cause a star on the Ecliptic to move about 1 arc-minute in 4 seconds, so precise measurements of absolute position were exceedingly difficult and required accurate and reliable clocks, which did not exist until after Harrison's invention of the regulator clock. Tycho Brahe achieved accuracies of 0.5 arc-minutes in relative (star to star) position measurements averaged over a number of observations.
3. Parallax measurements using large baselines require very precise clocks. Cesium atomic clocks (accuracy ??) are used for ???
Direct measurement of Astronomical Distances by Parallax. Parallax is the direct geometric measurement of changes in the direction of a stellar object when viewed at the extremes of a very long baseline. The first parallax measurements were done in the 1800s to measure the distance to the nearest stars. The accuracy and practical maximum distance that can be measured in this way depends on the length of the baseline and the precision of the angular measurement. The most accurate positioning at present is done in radio frequency astronomy using the Very Long Baseline Interferometer (VLBI) antenna arrays which receive signals from widely separated locations on the Earth. Of course the measurements depend on stellar objects that have suitable coherent radiations in these frequencies. The potential accuracy of current and planned VLBA precision is 10-6 arcseconds which equates to direct distance measurements out to 25 million lightyears. Recently, the galaxy NGC 4258 was measured at 23.5x 106 lightyears ± 7%, based on direct geometric triangulation. According to NASA, VLBI Radio Interferometry is hundreds of times more detailed than the Hubble Space Telescope and the dedicated Hipparcos parallax-measuring satellite.
The Goddard Space Flight Center VLBI Summary says "VLBI is a geometric technique: it measures the time difference between the arrival at two Earth-based antennas of a radio wavefront emitted by a distant quasar. Using large numbers of time difference measurements from many quasars observed with a global network of antennas, VLBI determines the inertial reference frame defined by the quasars and simultaneously the precise positions of the antennas. Because the time difference measurements are precise to a few picoseconds, VLBI determines the relative positions of the antennas to a few millimeters and the quasar positions to fractions of a milliarcsecond. Since the antennas are fixed to the Earth, their locations track the instantaneous orientation of the Earth in the inertial reference frame."
Reference on various cosmological models and computer simulations.