UC Irvine UC Irvine Previously Published Works Title Astrophysics in 1999 Permalink https://escholarship.org/uc/item/1jb99011 Journal Publications of the Astronomical Society of the Pacific, 112(770) ISSN 0004-6280 Authors Trimble, V Aschwanden, MJ Publication Date 2000 DOI 10.1086/316546 License https://creativecommons.org/licenses/by/4.0/ 4.0 Peer reviewed eScholarship.org Powered by the California Digital Library University of California PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC, 112:434È503, 2000 April ( 2000. The Astronomical Society of the PaciÐc. All rights reserved. Printed in U.S.A. Invited Review Astrophysics in 1999 VIRGINIA TRIMBLE Department of Astronomy, University of Maryland, College Park, MD 20742; and Department of Physics and Astronomy, University of California, Irvine, CA 92697 AND MARKUS J. ASCHWANDEN Lockheed Martin Advanced Technology Center, Solar and Astrophysics Laboratory, Department L941, Building 252, 3251 Hanover Street, Palo Alto, CA 94304 Received 1999 December 7; accepted 1999 December 7 ABSTRACT. The year 1999 saw the arrival of a star with three planets, a universe with three parameters, and a solar corona that could be heated at least three ways. In addition, there were at least three papers on every question that has ever been asked in astrophysics, from ““ Will the Universe expand forever? ÏÏ to ““ Does mantle convection occur in one or two layers? ÏÏ The answers generally were, ““ Yes,ÏÏ ““ No,ÏÏ and ““ None of the above,ÏÏ to each of the questions. The authors have done their best to organize the richness around centers deÐned by objects, methods, and madnesses. 1. INTRODUCTION 1.1. Hale You hold in your (real or virtual) hands the successor to You might feel this heading should be ““ Hail,ÏÏ but we ““ Astrophysics in 1991, 1992 ÏÏ and so forth, cited below as have in mind George Ellery, who started so many astrono- Ap91, Ap92, etc., and appearing somewhere near the begin- mical entities which still Ñourish (and see also Ap98, ° 10.8, nings of volumes 104 to 111 of PASP. In accordance with on the ““ tale ÏÏ of Comet Hale-Bopp). The American astrono- the policy that allows the old century and millennium to mical community welcomed something like 150 new Ph.D.s, end on 31 December 1999, ““ Astrophysics in 1999 ÏÏ clearly roughly a third of the world total. This number has crept ends a decade of reviews. Accordingly, we have taken some very slowly up over the past decades, but, in a strong con- liberties with the format, dismissing a great many impor- verse trend, the number of American astronomers applying tant, but long-standing, questions with a single answer, pro- for membership in the International Astronomical Union in vided by a single paper. Not always the Ðrst, or the last, or 1999 was about 85, down from 182 in 1987. even the most correct, but one that has the sound of a horn Happy anniversaries were celebrated by the American blowing at midnight. Astronomical Society and the American Physical Society The journals scanned were the issues that reached the (both 100 in 1999), the Astronomical Journal (with pub- library shelves between 1998 October 1 and 1999 Septem- lication at the beginning of Volume 117 of the papers from ber 30 of Nature, Physical Review L etters, Science, the an AAS session honoring its 150th), and the public planet- Astrophysical Journal (plus L etters and Supplement Series), arium, the Ðrst of which was built by Zeiss in Munich in Monthly Notices of the Royal Astronomical Society, 1924 and opened in 1925. It may or may not be a coin- Astronomy and Astrophysics (plus Supplements and cidence that a number of planetarium refurbishments are in Reviews), Solar Physics, Acta Astronomica, Revista Mexi- progress or just completed, including the Adler (Chicago), cana Astronomia y AstroÐsica, Astrophysics and Space Hayden (New York), Griffith (Los Angeles), and Stone- Science, Astronomy Reports, Astronomy L etters, AstroÐzica, henge (Salisbury). Mt. Stromlo Observatory also turned 75 Astronomische Nachrichten, Journal of Astrophysics and in 1999. If you want to spell out the full acronym, MSSSO, Astronomy, Publications of the Astronomical Society of it is essential to keep in mind that, because it is a dry Japan, Bulletin of the Astronomical Society of India, Baltic country, there is only one Siding Spring, but several Obser- Astronomy, New Astronomy, IAU Circulars, the solar vatories. physics portions of Astroparticle Physics, Journal of Geo- Inauguration and/or Ðrst light (not always in that order) physical Research, and Geophysical Research L etters, and, came for Subaru, Gemini North, the Ðrst mirror of the Very of course, Publications of the Astronomical Society of the Large Telescope (now called Antu; the others will be PaciÐc. Kueyen, Melinal, and Yepun), the Sudbury Neutrino 434 ASTROPHYSICS IN 1999 435 Observatory (well, perhaps not quite light), the new (single) Rosino, Patrick Fleming, Irving Segal, William Mesrobian, mirror of the (formerly) Multi-Mirror Telescope, and Barry Lasker, G. Edward Langer, Thomas Ogburn, NODO, the largest liquid mirror telescope. CHARA heli- William Blitzstein, Gerhard Herzberg, Heinrich Eichhorn, coptered the Ðrst of its telescopes to Mt. Wilson on January Ken Willcox, Rebecca Elson, Arne Slettebak, Boris Gar- 22, and the Green Bank Telescope is coming along. Indeed, Ðnkel, Margaret Russell Edmondson (elected a patron in a photograph stapled into NRAO Newsletter No. 81, it posthumously), Richard A. White, Oscar Monnig, Cornelis looks very much as if it were trying to scratch its head. Zwaan, Arthur Hoag, Paris Pishmish, Sidney Kastner, Reaching out into space, the reasonably happy Ñiers were Daniel Magnes Popper, Dorothy N. Davis Locanthi, and the Submillimeter W ave Astronomy Satellite (SW AS,on5 Henry W. Spreitzer. Special friends from abroad who December 1998), Deep Space 1 (October 1998), the Far departed during the year included Carlos Jaschek and Wil- Ultraviolet Spectroscopic Explorer (FUSE, June 1999), and helmina Iwanowska. the X-ray satellite Chandra (formerly AXAF) in late July of 1999. Carrying on with Ðrm upper lips were Cassini (swinging past Venus and Earth with its nuclear power source still 2. SOLAR PHYSICS intact), Galileo (safed through most of a Ñy-by of Europa, The almighty electronic search engine of the Astrophysics but back on the ether), NEAR (irresistibly, NEAR miss, Data System (ADS) reveals to us in a split second over 1000 which misÐred on 20 December 1998; but it passed close papers that have been published during the time frame of enough to Eros to measure its mass and size, and it gets 1998 OctoberÈ1999 September on solar topics. A speciÐed another chance to pass NEARer next year). And the Hubble search according to various subÐelds of solar physics Deep Field South joined its northern predecessor as a reveals a breakdown of the forefront interests (Table 1). In source of curious faint things for the whole community. the following we summarize the highlights in each subÐeld Our younger-sister publication, the Astrophysical in the same order. The total number of solar publications is Journal, acquired a new editor under far happier circum- somewhat less than the sum of items given in Table 1 stances than those attending the changing-of-the-guard at (because of the many overlaps), but the percentages should New England Journal of Medicine (Angell 1999). approximately reÑect the relative weight of activities in each Ðeld. 1.2. Farewell Surely the saddest of the institutional departures was that 2.1. The Musical Art of Solar Helioseismology of the Royal Greenwich Observatory, which closed its fourth and last set of doors on 31 October 1998. The Like the celebrated cellist Yoyo Ma exploring all kinds of National Radio Astronomy Observatory 140 foot corre- magic internal resonances of his musical instrument, solar lated its last fringes on 17 June 1999. Kitt Peak National helioseismologists continue to develop new acoustic sound- Observatory closed its 0.9 meter reÑector andcoude feed. ing techniques to probe the convective and radiative zones Mostly it needs to be fed money, and catering arrangements of the solar interior. The art of full-disk helioseismology has could conceivably be made. also been dubbed ““ repetitive music and the question of gap Above the atmosphere, MIR still orbits, but no one now Ðlling ÏÏ (Fossat et al. 1999), something that J. S. Bach mas- lives there. ROSAT did its last X-ray astronomy on 23 tered ingeniously 300 years ago. October 1998. And some missions were still-born, or nearly The accuracy of ““ global helioseismology ÏÏ is contin- so. A successful launch of ABRIXAS (an all-sky X-ray uously reÐned, providing crucial constraints on the helium survey instrument) was followed by battery failure. W IRE abundance (27.3%È27.7%, Brun et al. 1998; 24.8% ^ 0.2%, (the W ide-Field Infrared Explorer) also rose on schedule, in Richard et al. 1998, Basu,Dappen, & Nayfonov 1999b), the March, but lost the coolant essential for infrared sensitivity. inversion of the radial density structure of the solar/stellar Its 2A tracker telescope is, however, being used for very high interior, or the solar age (4.66 ^ 0.11 Gyr, Dziembowski et precision study of rapid variability of bright stars. Zhamya al. 1999). Deviations from standard solar models have 2.5 went to a watery PaciÐc grave on February 5. And recently been employed to derive anomalous solar energy winner of the ““ bad publicity award ÏÏ for 1999 was the Mars losses by the Primako† emission of axions (Schlattl et al. Climate Observer. Well launched on 10 December 1998, it 1999; Cebrian et al. 1999). failed the math part of its SAT and self-destructed in late Increased e†ort was spent on the inversion of the September. ““ tachocline ÏÏ (Hujeirat & Yorke 1998), a thin zone at the Colleagues who left us during the year (in the order in base of the convection zone which exhibits a high radial which the news was received) included American Astrono- gradient of the rotation rate, having a width of \ 0.05 mical Society members William Markowitz, Leonida (Corbard et al.