Astrophysics in 2003
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UC Irvine UC Irvine Previously Published Works Title Astrophysics in 2003 Permalink https://escholarship.org/uc/item/1tj090sf Journal Publications of the Astronomical Society of the Pacific, 116(817) ISSN 0004-6280 Authors Trimble, V Aschwanden, MJ Publication Date 2004-03-01 DOI 10.1086/383241 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, 116:187–265, 2004 March ᭧ 2004. The Astronomical Society of the Pacific. All rights reserved. Printed in U.S.A. Invited Review Astrophysics in 2003 Virginia Trimble Department of Physics and Astronomy, University of California, Irvine, CA 92697; and Astronomy Department, University of Maryland, College Park, MD 20742; [email protected] and Markus J. Aschwanden Lockheed Martin Advanced Technology Center, Solar and Astrophysics Laboratory, Organization ADBS, Building 252, 3251 Hanover Street, Palo Alto, CA 94304; [email protected] Received 2004 January 13; accepted 2004 January 13 ABSTRACT. Five coherent sections appear this year, addressing solar physics, cosmology (with WMAP highlights), gamma-ray bursters (and their association with Type Ia supernovae), extra-solar-system planets, and the formation and evolution of galaxies (from reionization to assemblage of Local Group galaxies). There are also eight incoherent sections that deal with other topics in stellar, galactic, and planetary astronomy and the people who study them. 1. INTRODUCTIONS for fun, without compulsive note-taking, were Observatory, Journal of the American Association of Variable Star Observ- Triskaidekaphobics may prefer not to read this installment ers, Astronomy and Geophysics, Mercury, New Scientist, Sky of ApXX, and their numbers may well be augmented even and Telescope, Monthly Notes of the Astronomical Society of before the introduction is over. This is, in fact, the 13th over- South Africa, and Journal of the Royal Astronomical Society view of 365.24 days of the astronomy and astrophysics liter- of Canada. ature. The earlier ones are cited here as Ap91, Ap92, …, Ap02 Do we ever cite ourselves? Well, now and then, but you are and appear in volumes 104–115 of PASP. The authors have supposed to be polite enough not to notice, and we promise to tried to read systematically the contents of about 30 journals do the same if you should ever indulge in self-citation. and other periodicals. Only about 10% of what has been read gets cited, and being cited is not always an unqualified 1.1. Lots of Launches compliment. Section 2 was assembled using papers found on the Astro- Up went: (1) Integral, a gamma-ray satellite on 17 October physics Data Service, maintained with support from NASA 2002; (2) GALEX, the galaxy evolution explorer satellite, the and including Solar Physics, Geophysics Research Letters, As- first designed to image most of the sky in ultraviolet and take troparticle Physics, Acta Astronomica Sinica, Chinese Journal spectra of much, on 28 April, with first images on 21 and 22 of Astronomy and Astrophysics, Journal of Geophysical Re- May; (3) Muses-C, which is supposed to hit asteroid 1998 SF36 search, as well as the journals scanned for the other sections. with a projectile and catch the dust, during the week of 8 May; Used in compiling sections 3–13 were the issues that reached (4) MOST (microvariability and oscillations of stars, the first library shelves between 1 October 2002 and 30 September 2003 Canadian astronomical satellite), which reached orbit on 30 of Nature, Physical Review Letters, Science,theAstrophysical June; (5) a coven of Mars missions, Mars Express, Beagle-2, Journal (plus Letters and Supplement Series), Monthly Notices Sprit, and Opportunity, in June and July; (6) SIRTF, the space of the Royal Astronomical Society, Astronomy and Astrophysics infrared telescope facility, on 25 August, with first images on (plus Reviews), Astronomical Journal, Acta Astronomica, Re- 1 September, and whether this was 2 days or 15 years late vista Mexicana Astronomı´a y Astrofı´sica, Astrophysics and depends on the point of view; (7) SMART-1, the first ESA Space Science, Astronomy Reports, Astronomy Letters, As- mission to the Moon on 27 September; (8) SORCE on 25 trofizica, Astronomische Nachrichten, New Astronomy, Journal January (a solar mission); and (9) the first Korean science of Astrophysics and Astronomy, Publications of the Astronom- satellite, carrying an ultraviolet astronomy instrument con- ical Society of Japan, Bulletin of the Astronomical Society of structed at the University of California, Berkeley, near the end India, Contributions of the Astronomical Observatory Skalnate of September. Pleso, IAU Circulars, and, of course, Publications of the As- On the ground, LIGO (the laser interferometric gravity ob- tronomical Society of the Pacific. Some of the journals read servatory) began a first science run; VIRGO (the European 187 This content downloaded from 128.200.104.165 on Wed, 18 Mar 2015 21:04:09 PM All use subject to JSTOR Terms and Conditions 188 TRIMBLE & ASCHWANDEN equivalent) expects first twitches in spring 2004. And the Polar the solar gravitational deflection angle of a graviton is equal Cap Observatory, which had been intended for a site near the to the light deflection angle (Ragusa & Ce´leri 2003). What north magnetic pole (unfortunately not located with the USA), about the gravitational constant? Wait for next year; the latest is to be replaced by several portable antennas that will operate seismic solar model is sensitive to Newton’s constant (Lopes first in Alaska and then in Canada. & Silk 2003), as well as to supersymmetric dark matter (Lopes et al. 2002b, 2002a). Does the Sun shine by pp or CNO nuclear 1.2. Holding Their Own fusion? New neutrino experiments set upper limits of 7.3% to Cassini returned its first Image of Saturn to the Jet Propulsion the fraction of energy that the Sun produces via the competing Laboratory about 1 November. Nozumi is still en route to Mars, CNO cycle, which is an order-of-magnitude improvement over but after a succession of problems may not be able to maneuver previous limits (Bahcall et al. 2003). Is the solar diameter con- effectively or return data. Rosetta, the comet mission whose stant? According to the analysis in the variation of f-mode delayed launch made its original destination impossible, is now global oscillations, there is no evidence that the Sun shrinks expected to head for Churymov-Gerasimanko in 2004. Star- (Antia 2003), while apparent variations are in phase or anti- dust, a comet sample return mission, set out in February 1999 phase with the solar cycle (Delmas & Laclare 2002; Noe¨l 2002) and should encounter its target, 81P/WILD2, in January 2004. or have a period of 515 days (Reis-Neto et al. 2003). Is the solar rotation constant? The equatorial rotation rate with a mean ע The comet has begun to display a dust tail, which is probably p a good thing. ofP 26.929 0.015 has been found not to vary over the SOHO, at age eight, has survived another glitch by using last 34 years (Haneychuk et al. 2003), but studies over longer its backup antenna to return data. Gravity Probe B (once called times find variations with an approximate 179 year cycle (Ja- the Stanford gyroscope experiment) is currently scheduled for varaiah 2003). The rotation rate of individual spot groups is a 2004 launch on a Delta rocket (which is either about a year found to increase with their age (Sivaraman et al. 2003) and or about 20 years late). there is a solar-cycle-related variation (Altrock 2003). Also, the mean photospheric magnetic field did not vary over the last 30 years (Kotov et al. 2002), although the high-frequency mean 1.3. Lots of Losses noise spectral density varies significantly (Chaplin et al. 2003). Down came, most notoriously, the Columbia shuttle on 1 Answers to these fundamental questions became possible only February 2002. BeppoSAX was returned deliberately to Earth because the solar interior quantities have been measured with (lest it return on its own someplace where it didn’t have an unprecedented accuracy: the adiabatic sound speed can be in- invitation) about 1 April, and Galileo immolated itself some- ferred to better than a few parts in 104, which becomes a serious where deep in the Jovian atmosphere on 21 September. Pioneer challenge to theoretical solar standard models (Boothroyd & 10 is still headed outward, but its last word, from 83 AU on Sackmann 2003). The largest uncertainties reside in the abun- 22 January, included no news of having reached the heliopause. dance of heavy elements, because the inversion from helio- Ground-based entities in various states of temporary or per- seismic data is ill-conditioned (Antia & Chitre 2002), but the manent suspension include (1) VERITAS (an ultra-high-energy new CNO reaction rates (Bahcall et al. 2003) might provide cosmic-ray detector), whose intended site is of importance to better abundance limits using the constraints of the total solar Native Americans; (2) closures of groups by the Max Planck luminosity. Society, including the radio astronomy program at Bonn; (3) the Gran Sasso underground laboratory, most of whose ex- periments were closed at the end of May (only temporarily, 2.1.2. Neutrino Mixing Holds Up we trust), including the construction of the solar neutrino fa- After the long-sought solution of the solar neutrino problem cility, Borexino, because of a possible fluid leak into the local reported last year (see Ap02), we are particularly eager to see water supply; (4) Mount Stromlo Observatory, which lost much a corroboration of the “noble-breaking” results. The theoretical of its library, shop facilities, and archives, and some of its interpretation of the neutrino phenomenology is currently being telescopes (including the Great Melbourne, which had recently investigated in the context of two-, three-, and four-neutrino completed the MACHO project) to wildfires on 18 January; mixing, from atmosphericnm oscillations, with the Kamioka and (5) all of humanity, though not perhaps for a century or Liquid Scintillator Antineutrino Detector (KamLAND), the so (Rees 2003).