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Astrophysics in 2004 Publications of the Astronomical Society of the Pacific, 117:311–394, 2005 April ᭧ 2005. The Astronomical Society of the Pacific. All rights reserved. Printed in U.S.A. Invited Review Astrophysics in 2004 Virginia Trimble Department of Physics and Astronomy, University of California, Irvine, CA 92697-4575; [email protected] and Markus Aschwanden Lockheed Martin Advanced Technology Center, Solar and Astrophysics Lab, Organization ADBS, Building 252, 3251 Hanover Street, Palo Alto, CA 94304 Received and accepted 2005 January 24; published 2005 April 15 ABSTRACT. In this 14th edition of ApXX,1 we bring you the Sun (§ 2) and Stars (§ 4), the Moon and Planets (§ 3), a truly binary pulsar (§ 5), a kinematic apology (§ 6), the whole universe (§§ 7 and 8), reconsideration of old settled (§ 9) and unsettled (§ 10) issues, and some things that happen only on Earth, some indeed only in these reviews (§§ 10 and 11). 1. INTRODUCTION Monthly Notes of the Astronomical Society of South Africa, The sequence of events leading up to Ap04 is very much and Journal of the Royal Astronomical Society of Canada. the same as in previous years. We read some papers, take some notes, make some selections, and write. Somewhere along the way, with luck, we also think. 1.1. Up Section 2 was assembled using papers found on the Astro- physics Data System (ADS), maintained with support from Our assumption is that the more astronomers and the more NASA. These include Solar Physics, Geophysics Research Let- facilities they have, the better. Thus the following successful ters, Journal of Geophysical Research, Astroparticle Physics, launches, inaugurations, and such all count as good news: Acta Astronomica Sinica, Chinese Journal of Astronomy and (1) Messenger to Mercury on 3 August, (2) two Chinese mag- Astrophysics, Advances in Space Science,andSpace Science netospheric satellites in January and July, (3) a new Kavli Reviews, as well as those used for the other sections. Institute for Cosmological Physics at the University of Chicago, Used in compiling sections 3–13 were the issues that (4) the April decision of Russia to join ESA, (5) the beginning reached library shelves (or, increasingly, V. T.’s mailbox) be- of actual data collection by Gravity Probe B on 27 August, 4 tween 1 October 2003 and 30 September 2004 of Nature, months into the 13-month mission (and we can’t wait to hear Science, Physical Review Letters,theAstrophysical Journal what its catchy new name will be when it is declared a success), (plus Letters and Supplement Series), Monthly Notices of the in the way that Muses C became Hayabusa after its May 2003 Royal Astronomical Society, Astronomy and Astrophysics launch, (6) the launch of Rosetta on 2 March, (7) the increase (plus Reviews), Astronomical Journal, Acta Astronomica, Re- to 30% (in 2001) of US high school students taking physics, vista Mexicana de Astronom´aı y Astrof´sicaı , Astrophysics (8) the capture of comet dust by Stardust on 2 January (it is and Space Sciences, Astronomy Reports, Astronomy Letters, due back in 2006 with its bits of Comet Wild 2), (9) the 60 Astrofizica, Astronomische Nachrichten, Publications of the antennas of LOFAR in place in fall 2004, (10) Shenzhou 5, Astronomical Society of Japan, Journal of Astrophysics and which put a third country into manned space programs on 15 Astronomy, Bulletin of the Astronomical Society of India, October 2003, (11) the expanded Sudbury facility planned by Contributions of the Astronomical Observatory Skalnate the Canadian Foundation for Innovation, (12) Mars arrivals by Pleso, New Astronomy (plus Reviews), IAU Circulars, and, Nozumi (13 December), Beagle 2 (25 December), Spirit of course, Publications of the Astronomical Society of the (4 June), and Opportunity (24–25 June), (13) an upturn in Pacific. Journals read less systematically and irregularly cited numbers of graduate students enrolled in engineering, science, include Observatory, Journal of the American Association of etc., nicely, as usual, mirror imaging the state of the economy, Variable Star Observers, ESO Messenger, Astronomy and and (14) the participants in IAU Colloquium 196, who, contrary Geophysics, Mercury, New Scientist, Sky & Telescope, to forecasts by a peer review group, had clear weather to see the 2004 transit of Venus from the same location where Jer- 1 Astrophysics in 1991 to 2003 appeared in volumes 104–116 of PASP. emiah Horrocks had been the first to record seeing such an They are cited here as Ap91, etc. event in 1639. 311 312 TRIMBLE & ASCHWANDEN 1.2. Down stellar photometer in mid December, (2) the American Terres- Conversely, losses of things, at any stage from preliminary trial Planet Finder and European Darwin (devices for direct budgets, to launches, to planned and unplanned mission ter- imaging) remain on the books at year’s end for deployment minations count as bad news, Sadly, a few entities appear in somewhere around 2020, and Eddington had slipped back into both the previous subsection and this one, including (1) No- the queue at midyear (though with its goal peculiarly described zumi,whichflew on past Mars in October, unable to stop, as “measuring the frequency of omitted light” Nature 429, 698), (2) Beagle 2, which never phoned home after leaving its Con- (3) RHESSI and INTEGRAL received special issues of appro- estoga wagon-equivalent (but leaving much ill feeling on all priate journals (ApJ Letters 595, No. 2, and A&A 411, No. 1, sides, e.g., Nature, 430, 954), and (3) Contour (a briefly “up” respectively), (3) Operations at the Gran Sasso Lab are slowly in August 2002) has now been understood to have died in three being restored to normal, but, in mid-May, Borexino was still separate pieces after overheating by exhaust gases and melting. on hold, and the Gallium Neutrino Observatory gone for good; And some other losses: (1) SWAS collected its last (sub- imagine all those wasted neutrinos who devoted their lives to millimeter) data on 23 July, (2) Midori II, an Earth-observation reaching terrestrial experiments, only to find no one waiting probe began to observe Earth from very close up on 31 October, for them. How many neutrinos? Well, just about all the solar B8 ones we had been expecting, according to S. N. Ahmed et (3) STIS, the Space Telescope Imaging Spectrograph on (cu- 7 riously) the Space Telescope closed up shop during the summer, al. (Physical Review Letters 92, 1813), and for the Be , proton- to be followed most of us very much fear by the entire HST proton, CNO, and other neutrino fluxes, we will just have to within the next couple of years, (4) SNOE,theStudent Nitro- possess our souls in patience. A next-generation neutrino ex- Oxide Explorer, ceased Exploring (atmospheric composition, periment is back in the plans in Japan after personal interven- we think, rather than students) on 13 December 2003 after a tion by Nobel Prize winner Masatoshi Koshiba (Nature 429, mission of 5 years and 290 days. It was allowed to burn up 746). Well, isn’t that what Nobel Prizes are for? on re-entry and so is presumably now part of the atmosphere is so assiduously explored. (5) Eddington, a high-precision pho- 1.4. Astronomers’ Ups and Downs tometric mission designed to looked for planetary transits and There were undoubtedly several hundred new ones, world- quivering stars has been removed from the ESA queue; various wide, receiving Ph.D.’s, including the first mainstream astron- NASA plans for investigations of “deep space” have also been omy Ph.D. from the University of California, Irvine, to Dr. delayed or worse, (6) Genesis, after collecting solar wind par- Tammy Bosler for work on the use of the infrared calcium ticles for months on end, returned to Earth on 8 September infrared triplet feature as an abundance indicator for stellar unfortunately at about 193 miles per hour (an upside-down population studies. accelerometer having failed to initiate parachute deployment), The losses were perhaps not quite so many, because there and they were picking bits of it out of the desert floor for were not so many Ph.D.’s given in 1950 or thereabouts, and weeks, (7) Los Alamos National Lab, closed for security con- again we note only one: Dr. Janet Mattei, long-time director 238 cerns, and so unable to assemble the required quantity of Pu of the American Association of Variable Star Observers and pellets to power an upcoming Pluto mission (carrying Pluto- an irreplaceable bridge between the amateur and professional nium to Pluto may or may not make you think of carrying communities. coals to Newcastle, which is, however, now a net importer), Two new concepts appear in Ap04, somewhere between up (8) Biosphere II, closing for lack of funding, fresh air, enthu- and down: The Garrison Keillor paper, proposal, or whatever, siasm, and so forth, (9) the Cambridge primate center, with meaning (like his joke book), pretty good, and the green dot, planning suspended at the beginning of calendar 2004 (the a symbol of surprise placed next to a few dozen papers during primates were probably not asked), (9) the New York WE-6 the elder author’s initial note-taking. All green dot papers have numbers, from which one had for one’s entire life been able been cited somewhere in the following pages. to learn upcoming weather and “At the tone, the time will be…” (New Yorker, 12 April, p. 29), ceased to operate on 24 March 2. THE SUN (the California equivalent disappeared long ago), and (10) one less Ph.D.-level physicist, because the University of Constance 2.1. The Solar Interior (Germany) took back that of J. H. Schoen for “undignified 2.1.1.
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