This is the online edition of In the Beginning: Compelling Evidence for Creation and the Flood
(7th Edition) by Dr. Walt Brown. The online version of the book is designed to be read online.
A PDF version or hardbound print version may be ordered.
Copyright © 1995–2008, Center for Scientific Creation. All rights reserved.
Click here to order the hardbound print edition of this online book.
Summarized below are the hard-to-explain details which any satisfactory theory for the origin of comets should largely explain.
Formation Mechanism. Experimentally verified explanations are needed for how comets formed and acquired water, dust particles of various sizes, and many chemicals.
Ice on Moon and Mercury. Large amounts of water ice are in permanently shadowed craters near the poles of the Moon, and probably on planet Mercury.
Crystalline Dust. Comet dust is primarily crystalline.
Near-Parabolic Comets. Most near-parabolic comets falling toward the Sun are doing so for the first time. [See Figure 147.]
Random Perihelion Directions. Comet perihelions are scattered on all sides of the Sun.
No Incoming Hyperbolic Orbits. Although a few comets leave the solar system on hyperbolic orbits, no incoming hyperbolic comets are known. That is, no comets are known to come from outside the solar system.
Small Perihelions. Perihelions of long-period comets are concentrated near the Sun, in the 1–3 AU range, not randomly scattered over a larger range.
Orbit Directions and Inclinations. About half the long-period comets have retrograde orbits (orbit in a direction opposite to the planets), whereas all planets, and almost all short-period comets, are prograde. Short-period comets have orbital planes near Earth’s orbital plane, while long-period comets have orbital planes inclined at all angles.
Two Separate Populations. Long-period comets are quite different from short-period comets. Even millions of years and many gravitational interactions with planets would rarely change one kind into the other.
Jupiter’s Family. Jupiter recently collected a large family of comets, each with a surprisingly short life expectancy of about 12,000 years.27 How did this happen? [See Figure 145 on page 264.]
High Loss Rates of Comets. Comets are being destroyed, diminished, or expelled from the solar system at rates that place difficult constraints on some theories.
Composition. Comets are primarily water, silicate dust (such as olivine), carbon dioxide, sodium, and many combinations of hydrogen, carbon, oxygen, and nitrogen. They contain limestone, clays, and some compounds found in or produced by life, such as methane.
Heavy Hydrogen. The high concentration of heavy hydrogen in comets means comets did not come from today’s known hydrogen sources—in or beyond the solar system.
Small Comets. What can explain the strange characteristics of small comets, including their abundance and proximity to Earth, but not to Mars? Small comets have never been seen impacting Mars.
Missing Meteorites. Meteor streams are associated with comets and have similar orbits. Meteorites are concentrated in Earth’s topmost sedimentary layers, so they must have fallen recently, after most sediments were deposited.55 [See “Shallow Meteorites” on page 36.] Comets may have arrived recently as well.
Recent Meteor Streams. As comets disintegrate, their dust particles form meteor streams which orbit the Sun. After about 10,000 years, solar radiation should segregate particles by size. Because little segregation has occurred, meteor streams, and therefore comets, must be recent. [See “Poynting-Robertson Effect” on page 38.]
Crater Ages. Are the ages of Earth’s impact craters consistent with each comet theory?