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Between Sun and Earth
  • Between Sun and Earth: timeline
  • In their own words: Robert Rosner
  • UCAR at 40
    Who We Are
    Introduction
    One Planet, One Atmosphere
    Between Sun and Earth
    Measuring and Modeling
    When Weather Matters Most
    Spreading the Word
    Knowledge for All
    Looking toward the Future
    UCAR at a Glance
    List of acronyms

    Robert Rosner is the William E. Wrather Distinguished Service Professor of astronomy and astrophysics, holding appointments as well in the physics department at the University of Chicago and the Enrico Fermi Institute. His research has involved analysis and modeling of solar and stellar observations and the study of fluid behavior in the laboratory and in space, especially in the context of stellar convection and stellar magnetic field generation. Rosner is a fellow of the American Physical Society. (Photo courtesy University of Chicago)

    Anyone visiting the High Altitude Observatory will immediately sense that HAO is different: it is much more akin to a university academic department than one would ordinarily expect of a research division at a national laboratory. I would like to comment on the justifications for maintaining (indeed, for celebrating) this difference at NCAR.

    Astrophysics as a distinct discipline—separate from astronomy—had its origins in the elucidation of visible light spectra from the Sun and stars. A number of the giants of 19th-century U.S. physics understood the tremendous potential importance of spectroscopy in revealing the fundamental nature of matter. Their work regarded the Sun as a representative astronomical object; relatively little attention was paid to the Sun in and of itself, or as the driver of activity within the solar system.

    With the advent of quantum mechanics in the 1920s, it became possible to connect observations of solar spectra to basic questions of physics. Two Harvard scientists central to the founding of HAO—Donald Menzel (director of the Harvard College Observatory) and his student Walter Orr Roberts—were in the thick of this kind of research in the late 1930s. As part of Menzel's drive to improve the observational prospects of this field, Harvard established HAO in Climax, Colorado. The coronal observations carried out at Climax have set the theme for much of the HAO science since.

    The tone of HAO science was also set early on by the connection to Harvard's astrophysical research. This view of solar science, which sees the Sun as an intrinsically interesting object, motivated most of HAO's expansion as part of NCAR. Fundamental work on radiative hydrodynamics, the solar wind, the solar dynamo, helioseismology, and (most recently) stellar activity all reflect this perspective on solar physics. HAO has played an important international role in solar physics; in certain important subfields of astrophysics, it is the primary U.S. institution.

    I contend that Walt Roberts's scientific motivation for joining HAO with NCAR—namely, investigating the terrestrial impacts of the Sun—was both extremely insightful and scientifically premature. Connections between solar activity and climatological or meteorological phenomena have proven extremely difficult and subtle to establish. It is only recently, with modern observational tools and analysis methods, that such connections are being established and Roberts's vision vindicated. With these successes, I predict that solar physics within HAO will experience yet more strongly the natural, and hopefully creative, tension between the basic and more applied sciences. The challenge for HAO will be to balance the historical pressure for excellence in basic solar science with the increasing pressures for practical relevance. (Of course, this tension between basic, unfettered research and applications-driven research pervades not just HAO but much of NCAR as well.)

    As the connections between solar physics and the atmospheric sciences grow stronger, and are placed on increasingly firmer quantitative grounds, I see HAO in a unique position to benefit both itself and the larger scientific community from the interplay between the fundamental and the practical aspects of the science. I therefore salute HAO and its scientists for what they have wrought, and I am excited about their future.

    UCAR at 40
    Who We Are
    Introduction
    One Planet, One Atmosphere
    Between Sun and Earth
    Measuring and Modeling
    When Weather Matters Most
    Spreading the Word
    Knowledge for All
    Looking toward the Future
    UCAR at a Glance
    List of acronyms


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    Last revised: Fri Jan 26 17:18:32 MST 2001