UC Irvine UC Irvine Previously Published Works Title Astrophysics in 2002 Permalink https://escholarship.org/uc/item/8rz4m3tt Journal Publications of the Astronomical Society of the Pacific, 115(807) ISSN 0004-6280 Authors Trimble, V Aschwanden, MJ Publication Date 2003 DOI 10.1086/374651 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, 115:514–591, 2003 May ᭧ 2003. The Astronomical Society of the Pacific. All rights reserved. Printed in U.S.A. Invited Review Astrophysics in 2002 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, Department L9-41, Building 252, 3251 Hanover Street, Palo Alto, CA 94304; [email protected] Received 2003 January 29; accepted 2003 January 29 ABSTRACT. This has been the Year of the Baryon. Some low temperature ones were seen at high redshift, some high temperature ones were seen at low redshift, and some cooling ones were (probably) reheated. Astronomers saw the back of the Sun (which is also made of baryons), a possible solution to the problem of ejection of material by Type II supernovae (in which neutrinos push out baryons), the production of R Coronae Borealis stars (previously-owned baryons), and perhaps found the missing satellite galaxies (whose failing is that they have no baryons). A few questions were left unanswered for next year, and an attempt is made to discuss these as well. 1. INTRODUCTION subscription, which magically reappeared a few months later), and Monthly Notices of the Astronomical Society of South Astrophysics in 2002 completes a round dozen in the series. Africa. The previous 11 reviews are cited here as Ap91, Ap92, etc., In accordance with the long-standing principle that our own to Ap01, and appear in volumes 104–114 of PASP. The game works are not to be regarded as highlights of the year, any plan has been more or less as usual. The authors read a good paragraphs containing citations to papers by V. Trimble should deal more than they take notes on and take notes on many be deemed to have been written by M. J. Aschwanden, and more papers than can be mentioned here. conversely (some of them actually were). Section 2 was assembled using papers found on the Astro- It was a year of ups and downs, especially for satellites, physics Data Service, maintained with support from NASA. HESSI,theHigh Energy Solar Spectroscopic Imager, after a The journals scanned for sections 3–13 were the issues that successful launch, became R (for Ramaty) HESSI when it reached library shelves between 1 October 2001 and 30 Sep- started collecting data in February 2002. The CASLEO 2.15 tember 2002 of Nature, Physical Review Letters, Science,the meter telescope is now the Jorge (pronounced, he insists, Astrophysical Journal (plus Letters and Supplement Series), George) Sahade telescope. A Cerenkov detector for high energy Monthly Notices of the Royal Astronomical Society, Astronomy cosmic rays is now operating in Namibia (Steenkamp 2002). and Astrophysics (plus Reviews), Astronomical Journal, Acta And ARCHEOPS (a balloon-borne device to look at the cosmic Astronomica, Revista Mexicana Astronomia y Astrofisica, As- trophysics and Space Science, Astronomy Reports, Astronomy microwave background) traveled from Karuna, Sweden, to Si- Letters, Astrofizica (happily back among the living), Astron- beria on 7 February 2002. This trip cannot (yet) be made by omische Nachrichten, New Astronomy, Journal of Astrophysics ship, but opening of a Northwest Passage (see the Earth section, and Astronomy, Publications of the Astronomical Society of § 11.3) must surely someday be followed by a Northeast Pas- Japan, Bulletin of the Astronomical Society of India, Baltic sage, though ships will probably still not be the best platform Astronomy, Contributions of the Astronomical Observatory for microwave telescopes. Skalnate Pleso, IAU Circulars, and, of course, Publications of Genesis lives at L1 and has been collecting solar wind since the Astronomical Society of the Pacific. Some of the journals November 2001. MAP lives at L2 and has been collecting we read for fun, without systematic note-taking, were Obser- cosmic microwave photons for about the same length of time. vatory (occasionally so much fun it should be rated PG for The LDEF (Long Duration Exposure Facility) lived in near Professorial Guidance suggested), Journal of the American As- Earth orbit for much longer than had been planned, since it sociation of Variable Star Observers, Astronomy and Geo- went up before the Challenger explosion and could not come physics, Mercury, Sky and Telescope (until they terminated our down until long after. Its much-battered surfaces collected 514 ASTROPHYSICS IN 2002 515 no measurable SIMPS (strongly interacting massive particles, also dissect our astronomical Sun into microsystems from in- Javorsek et al. 2002), but the implications for their (non)- side to outside, such as micropores (Lites et al. 2002), the contribution to dark (?) matter are infinitely model dependent. microstructure of solar magnetic fields (Sanchez-Almeida MINISAT was launched in April 1997 and completed op- 2001), and coronal microflares (Shimizu et al. 2002), or propose eration in April 1999. We’re embarassed at having missed it a reconnection and microscale (RAM) mission (Bookbinder et completely until workshop proceedings were published (Gi- al. 2002). menez 2001). It was a Spanish mission that mapped diffuse ˚ emission at 300–1050 A and monitored sources at 10–100 keV. 2.1. Solar Neutrinos and WIMPs The European Space Agency decided in May not to carry on with Venus Explorer, but kept GAIA (an astrometric mis- There are good and bad news in solar neutrino physics. The sion) and Solar Orbiter (which, we think, is probably supposed good news: Raymond Davis, Jr., deservedly, was awarded the 37 to orbit the Sun) in their queue. GAIA has an estimated launch 2002 Noble Prize in Physics for his 40-year-long Cl solar date in 2012 and may have to work very hard, since the Amer- neutrino measurements. The bad news: On November 12, 2001, ican precursor, FAME (the AM part stands for Astrometric about 60% of the photomultipliers used for the Super-Ka- Mapping) has slipped from budgets and the German precursor miokande detector were destroyed in an accident that happened DIVA has slipped to 2007–2008 at the earliest. as a chain reaction following the implosion of a faulty pho- Pioneer 10 can no longer be counted upon to call home, but tomultiplier. On the bright side, the solar neutrino problem has 30 years after its March 1972 launch, it responded when called. been pretty much settled by the Sudbury Neutrino Observatory 8 The Very Large Telescope began operation with two-to-four (SNO) experiment, from which a B neutrino flux of 86Ϫ2 Ϫ1 cm s was inferred (Ahmad 10 # (0.99 ע 8-meter mirrors in an interferometric mode, and adaptive optics F(B)p (5.44 with a laser guide star began at Keck on 23 December 2001. et al. 2001), which agrees well with the predictions of the best We have not come up with a good enough remark about the standard solar models and is consistent with the trinity of the Laser of Bethlehem to bother but would be grateful for electronic, muonic, and tauonic neutrinos. This boron neutrino suggestions. flux constrains also the metallicity of the accretion of our proto- And some good things came down during the year, which solar cloud, which can be tested now with p-mode oscillation counts as bad news. These include EUVE (Extreme Ultraviolet data, yielding an upper limit of ≈2 solar masses of iron, or Explorer), with atmospheric re-entry on 30/31 January 2002, ≈40 solar masses of meteoric material (Winnick et al. 2002). and BeppoSAX on 30 April 2002. HETE-I and SAC-B returned A still unknown property of solar neutrinos is their magnetic to Earth in early April 2002, still locked face to face, without moment. If they have a nonzero magnetic moment, variability having ever done any of the science for which they were in- of the neutrino flux by an inhomogeneous magnetic field in tended. Contour (COMet Nuclear TOUR) broke into three the solar interior could result. Recent histogram analysis of pieces as it was being boosted out of near Earth orbit in August GALLEX-GNO and SAGE data indicates that the solar neu- 2002. Apparently all three pieces went off in roughly the right trino flux, in the energy range of gallium experiments, varies direction. on a timescale of weeks. A “resonance statistic”, which takes Yohkoh, the Japanese solar satellite, was lost on 13 December the depth dependence of the internal rotation rate into account, 2001 because an erroneous command was uploaded by acci- yields strong evidence that modulation of the neutrino flux is dent. Well, you might think, surely no one would load a “self- occurring in the convection zone, and no evidence that mod- destruct” command on purpose; but remember what happened ulation is occurring in the radiative zone (Sturrock & Weber to the Compton Gamma Ray Observatory (CGRO) not so very 2002). long ago. Even more exotic, helioseismology can now be used to infer They are still launching rockets at Baikonur, Kazhakstan, the presence of dark matter in the solar neighborhood. If weakly from whence Sputnik went up in 1957, but the intention is for interacting massive particles (WIMPs) accumulate in the center it to wind down by 2005. Saddest of all, the paper version of of the Sun, they transfer additional energy from the solar core Astronomy and Astrophysics Abstracts, successor to Astron- and change the luminosity of the Sun up to ≈0.1%, which is omische Jahresberichte, founded in 1898, has ceased to exist, now within the reach of helioseismic detection.