Re: Why YEC?

From: Allen Roy (
Date: Wed Aug 22 2001 - 15:14:54 EDT

  • Next message: William T. Yates: "Re: Numbers an "historian"?"

    From: Todd S. Greene <>
    > At my website I have archived a discussion in which the YECs (one a
    > preacher and on an applied physics professor) put forward the
    > YEC-honored argument that "evolutionists have no explanation for
    > short-term comets." Seeing the promotion of this blatant error, I
    > immediately pointed out that not only do astronomers (not evolutionists)
    > have a good, reasonable explanation for short-term comets (the Kuiper
    > Belt), but they have had this explanation since the early 1950s (i.e.,
    > for at least 35 years), and -- even worse for their YEC argument -- this
    > explanation had been getting empirical verification, due to advances in
    > astronomical instrumentation -- beginning in 1992.

    Here is an interesting abstract concerning comets and the Kuiper Belt which
    indicates a lack of explanation for short-term comets. It was supplied to
    me by a YEC astronomy professor.

    Title: Why we need detailed visible-range spectral data on Kuiper belt
    Authors: Busarev, V. V.
    Affiliation: AA(Sternberg State Astronomical Institute, Moscow University)
    Journal: American Astronomical Society Meeting 198, #70.05
    Publication Date: 05/2001
    Origin: AAS
    Abstract Copyright: (c) 2001: American Astronomical Society
    Bibliographic Code: 2001AAS...198.7005B


    Our understanding of Kuiper belt objects (KBOs)' nature may be based on two
    general scenarios of their origin. First, they could result
    from early accretional phases of the Solar System ``in situ". Then they are
    probably the most primitive and unprocessed bodies among known and should be
    mostly icy, with a very low content of silicate component. Second, a
    considerable portion of them (if not a majority) might have been thrown by
    Jupiter and other giant planets from their zones of accumulation. If so,
    they could include much more silicates (possibly up to 40%). To check the
    suppositions we need high-resolution visible and near-infrared spectral data
    on Centaurs (as possible `fugitives' from the Kuiper belt) and the KBOs.
    Because of faintness of the objects their physicochemical properties remain
    still little-known. Visible-range observations of the bodies by means of a
    spacecraft approaching to the belt could much help in solving the problem.

    Visible-infrared spectrophotometric observations of the objects showed a
    considerable diversity among them (Jewitt D. & J. Luu, 1998, Astron. J.,
    115, 1667-1670). It hints at a diversity in content of their matter.
    Spectral features of ices could not probably dominate in the visible range
    spectra of silicate-bearing KBOs. Reflectance spectra of principal gases'
    frosts are mainly flat and featureless in the range (Wagner J. K. et al.,
    1987, Icarus, 69, 14-28). Besides, silicates of KBOs are probably oxidized
    and hydrated to a high extent. Highly hydrated main-belt C-class asteroids
    have absorption bands at 0.43 and 0.6-0.8 microns (up to about 5%) (Vilas F.
    & M. J. Gaffey, 1989, Science, 246, 790-792 and
    Vilas F. et al., 1993, Icarus, 102, 225-231). Similar spectral features
    attributed to oxidized and hydrated silicates were also found on many M- and
    S-asteroids (e. g., Busarev V. V., 2001, LPSC XXXII, abstract 1927). The
    absorption bands are interpreted as caused by electronic processes in a bulk
    of oxidized silicates and hydrated clay minerals including structural
    OH-groups. Thus, the absorption features may be considered as indicators of
    a presence of oxidized and/or hydrated silicates on a solid body regardless
    of its position in the Solar System. For these reasons we have started
    visible-range spectroscopic observations of Centaurs and the KBOs on Russian
    6-m telescope

    This archive was generated by hypermail 2b29 : Wed Aug 22 2001 - 15:16:28 EDT