The Scale of the Universe
In April 1920, Harlow Shapley and Heber D. Curtis first debated The Scale of the Universe in the main auditorium of Smithsonian's Natural History Museum in Washington, DC. In April 1996, Sidney van den Bergh and Gustav A. Tammann again debated "The Scale of the Universe" in the same auditorium. The 1996 debate centered on the recent controversies surrounding the determinations of Hubble's constant - the expansion rate of the Universe. This single number, named for astronomer Edwin Hubble, parametrizes the size and age of our Universe. Interpreting recent observational results from space borne and ground based telescopes, two large camps emerged backing different values of Hubble's constant. At the 1996 Scale of the Universe debate, champions for each camp outlined their arguments.
Debate Proceedings: Six published papers from the 1996 debate
which appeared in the 1996 December Publications of the Astronomical
Society of the Pacific. Included are the two introductory talks, an opening
by the organizers, and a closing by the moderator.
The Scale of the Universe Debate in 1996 by Bonnell, Nemiroff & Goldstein
The Scale of the Universe: A Curtain-Raiser in Four Acts and Four Morals by Owen Gingerich
H_0: The Incredible Shrinking Constant, 1925-1975 by Virginia Trimble
The Hubble Constant: A Discourse by Gustav A. Tammann
The Extragalactic Distance Scale by Sidney van den Bergh
Is H_0 Well Defined? by John N. Bahcall
About the 1996 Debate: Background information about the 1996 is
The Program distributed at the 1996 Scale of the Universe Debate. The program includes an introduction, the schedule of events, and a brief profile of all the program participants.
Images from the debate.
Comments about the debate. Comments from people who attended.
Historical Background: In addition to Trimble's and Gingerich's
historical introductions listed above, below find papers published involving
Edwin Hubble and his role in the determination of the constant
that bears his name:
A Relation Between Distance and Radial Velocity Among Extra-Galactic Nebulae published in 1929 by Edwin Hubble
The Large Radial Velocity of N.G.C. 7619 by M. L. Humason
Edwin Hubble 1889-1953 an obituary by Allan Sandage
Edwin Powell Hubble, Biographical Memoirs by N. U. Mayall
Scientific Background: Below find links and lists intended for students, educators, and the generally inquisitive.
Edwin Hubble Discovers the Universe an Astronomy Picture of the Day about Edwin Hubble
M100 and the Expanding Universe an APOD about the modern quest to determine Hubble's constant. Follow the links to find out more.
Hubble at the 100-inch Hooker Telescope from Mount Wilson Observatories On-Line Archives
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