Authors: O. Zamora, C. Abia, B. Plez, I. Domínguez and S. Cristallo
A&A 508, 909 (2009) Received 7 July 2009 / Accepted 17 September 2009
Keywords: stars: abundances, stars: chemically peculiar, stars: carbon, stars: AGB and post-AGB

Authors: J. Sánchez Almeida and K. Ichimoto
A&A 508, 963 (2009) Received 19 May 2009 / Accepted 17 September 2009
Keywords: Sun: magnetic fields, Sun: photosphere, sunspots

Authors: E. I??k and V. Holzwarth
A&A 508, 979 (2009) Received 3 July 2009 / Accepted 22 September 2009
Keywords: Sun: interior, Sun: magnetic fields, magnetohydrodynamics (MHD)

Authors: K. M. Schure, D. Kosenko, J. S. Kaastra, R. Keppens and J. Vink
A&A 508, 751 (2009) Received 14 May 2009 / Accepted 24 September 2009
Keywords: hydrodynamics, ISM: evolution, radiation mechanisms: thermal

Authors: K. Iwasaki and T. Tsuribe
A&A 508, 725 (2009) Received 1 July 2009 / Accepted 14 September 2009
Keywords: hydrodynamics, instabilities, ISM: kinematics and dynamics, ISM: structure, ISM: clouds

Authors: G. Vigeesh, S. S. Hasan and O. Steiner
A&A 508, 951 (2009) Received 8 May 2009 / Accepted 10 September 2009
Keywords: Sun: magnetic fields, Sun: photosphere, Sun: faculae, plages, magnetohydrodynamics (MHD), waves

Authors: R. Falewicz, P. Rudawy and M. Siarkowski
A&A 508, 971 (2009) Received 29 June 2009 / Accepted 18 September 2009
Keywords: Sun: chromosphere, Sun: corona, Sun: flares, Sun: magnetic fields, Sun: X-rays, gamma rays

Authors: A. S. M. Burgess, E. Moraux, J. Bouvier, C. Marmo, L. Albert and H. Bouy
A&A 508, 823 (2009) Received 7 May 2009 / Accepted 21 August 2009
Keywords: stars: formation, stars: low-mass, brown dwarfs, open clusters and associations: individual: IC 348, stars: luminosity function, mass function, infrared: stars

Authors: B. Parise, S. Leurini, P. Schilke, E. Roueff, S. Thorwirth and D. C. Lis
A&A 508, 737 (2009) Received 26 June 2009 / Accepted 18 September 2009
Keywords: astrochemistry, line: identification, line: formation, ISM: abundances, ISM: individual objects: Orion Bar, ISM: molecules

Authors: N. Gai, S. L. Bi, Y. K. Tang and L. H. Li
A&A 508, 849 (2009) Received 3 May 2009 / Accepted 18 September 2009
Keywords: stars: evolution, stars: interiors, stars: oscillations

Authors: S. De Grandi and S. Molendi
A&A 508, 565 (2009) Received 22 June 2009 / Accepted 27 August 2009
Keywords: X-rays: galaxies: clusters, galaxies: clusters: general, supernovae: general, galaxies: abundances, cooling flows, intergalactic medium

Authors: D. Barrado, M. Morales-Calderón, A. Palau, A. Bayo, I. de Gregorio-Monsalvo, C. Eiroa, N. Huélamo, H. Bouy, O. Morata and L. Schmidtobreick
A&A 508, 859 (2009) Received 4 April 2009 / Accepted 22 September 2009
Keywords: circumstellar matter, stars: formation, stars: low-mass, brown dwarfs, stars: pre-main sequence, infrared: stars

Authors: S. Kraus, K.-H. Hofmann, F. Malbet, A. Meilland, A. Natta, D. Schertl, P. Stee and G. Weigelt
A&A 508, 787 (2009) Received 26 July 2009 / Accepted 28 October 2009
Keywords: stars: pre-main-sequence, circumstellar matter, accretion, accretion disks, planetary systems: protoplanetary disks, planetary systems: formation, techniques: interferometric

Authors: M. Galametz, S. Madden, F. Galliano, S. Hony, F. Schuller, A. Beelen, G. Bendo, M. Sauvage, A. Lundgren and N. Billot
A&A 508, 645 (2009) Received 23 July 2009 / Accepted 28 September 2009
Keywords: galaxies: ISM, galaxies: dwarf, infrared: ISM, dust, extinction

Author: L. Belluzzi
A&A 508, 933 (2009) Received 21 July 2009 / Accepted 6 August 2009
Keywords: atomic processes, polarization, scattering, Sun: atmosphere

Recently some people have claimed that the Sun
is entering a new Maunder Minimum—a decades-long period
of few sunspots—and that this will cause the Earth's
atmosphere to cool.  The Sun is certainly quiet in 2008,
but this is the normal quiet of a minimum in the 11 year
sunspot cycle.  Clearly the tendency to interpret normal
variations as fundamental changes is not confined to the
global warming alarmists.

Carbon and oxygen are converted into nickel
in a white dwarf through a complex network of reactions.
The incremental changes tend to follow the series of atomic
nuclei that are multiples in composition of the helium
nucleus.  For this reason, large amounts of neon-20,
magnesium-24, silicon-28, and other elements with equal
and even numbers of protons and neutrons are created.  But
the reactions also tear down nuclei, creating many free
protons, neutrons, and helium nuclei that combine with
other atomic nuclei to produce elements and isotopes
that do not have equal numbers of protons and neutrons
or do not have an even number of protons or of
neutrons.  Because thermonuclear fusion disrupts
a white dwarf, the thermonuclear reactions in
a white dwarf  contribute to the rich variety
of chemical elements and isotopes we find throughout
the universe.

The structure of a brown dwarf is set by
degeneracy pressure.  Unlike a star, where the mass
sets both the radius and the photospheric temperature,
a brown dwarf has a radius and temperature that is nearly
independent of its mass.  All brown dwarfs are about
the same size as Jupiter.  The photospheric temperature
of a brown dwarf is set by its age, although the lifetime
of a brown dwarf is set by the mass.  Because the
low-mass brown dwarfs cool much faster than the
high-mass brown dwarfs, infrared surveys preferentially
find the more-massive brown dwarfs.

The most energetic supernovae are powered by gravitational potential energy.
Once a massive star consumes all of its thermonuclear fuel, it is unable to support
itself against its own gravity.  The core of such a star collapses to a neutron star.
The birth of a neutron star is heralded by a burst of neutrinos that blows apart
the remainder of the star.  We see this expanding debris as a supernova.

The Large Hadron Collider at CERN, a machine
that accelerates protons to very high energies and then
bangs them together, began operating on September 10, 2008.
Some believe this machine threatens Earth. They need not
worry, because the particle collisions created in this
machine occur daily when cosmic rays strike Earth's
atmosphere. Man can't yet rival nature's extremes.