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		Black Holes Black Holes (BHs) describe the ultimate state of sufficiently compressed matter of arbitrary mass: mini ( 10¹⁵g), midi, and maxi ( 10³⁴g). The literature talks of more than 10² of identified (maxi) BHs, both of stellar mass (10^{1 ± 0.5} Msun, in X-ray binaries), and of galactic mass (supermassive, 10^{7.5 ± 2}Msun, in the nuclei of galaxies). Yet there are hurdles to BH formation, such as centrifugal, radiative, and nuclear detonative - hence BHs are likely very rare - and what has been proposed is too variable and has too strong winds, and too hard a spectrum for an accreting BH. It conforms much better with a dense accretion disk, either around a neutron star, or the central part of a galactic disk. Search for references 159, 206, 209, 225, 229, 230, 247, 260, 267, 268. Critical Thoughts on Cosmology (.ps version) Jürgen Ehlers - and the fate of the black-hole spacetimes (.ps version)

		Cosmic Rays Cosmic Rays (CRs) are the relativistic particles, both hadrons and leptons, which flood the disk of our Milky-Way Galaxy and probably equally so its halo - though not the SMC - with ion energies from below rest energy all the way up to 10^20.5eV, a macroscopic quantity. They are H- and He-deficient. Whereas most of them are trapped by the disk's magnetic fields for some 10⁷ years, those above some 10¹⁹eV cross the disk in only 10^2.5yr, and therefore consume almost 1% of the total power of the CR sources. Some 20% of the CRs above 10²⁰eV are repeaters, i.e. arrive repeatedly from the same direction (within 1^o). In my understanding, they are all boosted by the indented and corotating magnetosphere of a Galactic neutron star, probably a suffocated pulsar (of age 10^6.4yr. This population may well be identical with the sources of the gamma-ray bursts. Search for references 78, 192, 216, 230, 247, 253, 266. Cosmic Rays and Gamma-Ray Bursts (.ps version) ISM, Cosmic Rays, and the Shape of the Heliosphere (.pdf version)

		Gamma-Ray Bursts Earth is hit daily by some three gamma-ray bursts, almost isotropically from all directions, of durations between ms and hour but centred on 1s. Temporal fine structure reaches down below ms, reminiscent of neutron-star sources. Each two bursts have different, mostly composite light curves, with subbursts of exponentially decaying hardness. Afterglows have broadband, whitish spectra, reminiscent of light echoes, and fade as broken power laws during many months, with redshifted emission and absorption lines, predominantly from iron. For distances of a few 10²pc, their energetics conform with neutron-star sources during spasmodic accretion. Their relativistic redshifts are reminiscent of SS 433, and the 5 repeaters among them look like the nearest of them. None of the tentative 'identifications' with (faint) galaxies at cosmic distances is without serious problems. Search for references 194, 201, 216, 230, 233, 243, 266, 269. Corresponding articles: Gamma-Ray Bursts: their Sources Cosmic Rays and Gamma-Ray Bursts (.pdf version) The Local-Galactic interpretation of the Gamma-Ray Bursts

		Jet Sources Jet sources are ubiquitous in the sky, driven by (1) active galactic nuclei (AGN), by (2) (mostly binary) neutron stars, (3) (binary) forming white dwarfs, and by (4) (all?) newly forming stars (YSOs). Here I classify the BHCs as (binary) neutron stars surrounded by heavy accretion disks, see "Black Holes". The jets can be thinner than 1% in angle, sided, and expand superluminally. They never branch, blow cocoons, and can have several successive seeming heads. For all of them, my understanding of their formation (since 1980) is the generation of extremely relativistic e^±-pair plasma in magnetospheric reconnections - like on the Sun - whose buoyant escape along the density gradient, viz. the spin axis, rams two antipodal channels through which subsequent generations escape in the form of an ordered, mono-energetic ExB-drift w.r.t. inherited toroidal B-fields, and perpendicular (Hall) E-fields in equi-partition. Search for references 101, 102, 207, 229, 230, 246, 247, 253; Cf. M. Livio in Nature 417, 125 (2002) for the 'general' opinion. The Physics of E x B Drifting Jets, The Astrophysical Jets (.pdf version), The Astrophysical Jets (long version) (.pdf version), Black Holes Cannot Blow Jets (.pdf version)

		Massive Stars For many years, stars have been thought to weigh less than 90 Msun, probably even less than 60 Msun. In present years, the estimate has gone up to several 10² Msun, based largely on Eddington's luminosity criterion: M / Msun L / LEdd(Msun), LEdd(Msun) = 10^4.5 Lsun. But as pointed out by Nir Shaviv (Ap.J. 532, L137), Rayleigh-Taylor instabilities can reduce a star's atmospheric blanketing capability considerably. Another possible oversight is the presence of a neutron star plus (heavy) accretion disk in the system, even around a seemingly single star, to be inferred from the (radio and X-ray) wings of its spectrum, and from the occurrence of large outbursts on short timescales (compared with the star's thermal timescale). The stellar luminosity function of the Local Group terminates sharply at 10⁷ Lsun; among the few best-studied cases of extreme mass is Eta Carinae, which may be a triple-star system involving component masses of 40 Msun. Search for references 242, 247.

		SS 433 SS 433, the 433^rd entry in the 1977 catalogue of variable stars by Stephenson and Sanduleak, has made many headlines ever since its presentation at the 1978 Texas Symposium on Relativistic Astrophysics held in Munich. It combines the properties of (i) a compact, high-mass Galactic X-ray binary involving an ejecting neutron star (or BHC), (ii) a bipolar flow mapped -- spatially and spectrally -- on length scales between 10^13.7cm(d/3Kpc) and 10^20.3cm, at frequencies ranging from radio all the way up to hard X-rays, in interaction with (iii) the 10⁴yr old SN shell W50 which is thought to have given birth to the central neutron star, and with (iv) periodic variabilities of the emissions with the orbital period P = (13.0820 ± 0.03)d, precessional period P_prec = (164.0 ± 4)d, and with several beat periods of the two, including nodding at P_nodd = (2P^-1 + P_prec ^-1)^-1, plus correlated stochastic variabilities down to 5 min. So far unique are its two sets of periodically blue- and redshifted optical and X-ray emission lines from highly ionized H, He, Fe, Ni, Mg, Ca, Si, S, Ar, and Ne. Many properties of the system are controversial, such as its distance, masses, energetics, orientation, composition, jet speed, mode of precession, and mode of jet formation, leading to various discrepancies which go away when one replaces Milgrom's assumption -- of an orderly precessing heavy jet substance in straight-line motion -- by relativistically escaping pair plasma which drags along channel-wall material at transrelativistic speeds, like 'bullets', from the pierced, interacting windzone of the active binary system. Search for references 107, 184, 207, 216, 217, 230, 247.

		Supernova Explosions Following Shklovskii (1962), supernova (SN) explosions of massive stars (M 5 Msun) tend to be treated as strong shock waves, like (thin-walled) pressure bombs, instead of as (thick-walled) splinter bombs, with a Hubble-flow velocity distribution of more than 10⁴ magnetized filaments. Core collapses of supergiant stars with {He, H} in their envelopes give rise to SNe of (spectral) type {I, II}, and the compactness of their envelopes influences the subclassifications {a, b, c, d, ... and P, L, b, n, ...} for {red, blue} progenitors (with their {shallower, deeper} potential wells). Ever since 1976, I am convinced that SNe are driven by the spin energy of the collapsing core which is transiently transferred to a 'magnetic spring' that propels the innermost mantle, and subsequently decays into a relativistic cavity, both leptons and hadrons. Under expansion, this extremely relativistic piston completes the launch, and gives rise to a UV flash when it crosses the photosphere, locally on the timescale of a ms but reaching us on the timescale of minutes. Search for references 77, 174, 216, 230, 242, 247, 264. Supernovae, their functioning, lightcurves, and remnants.(pdf. version)
		Tunguska 1908 The largest catastrophe reported by mankind was the flattening, and partial incineration, of some 10^3.3 Km² of trees at 7.15 a.m. on June 30 1908 in the Siberian taiga, slightly north of the river Stony Tunguska. It has been interpreted as caused by the impact of some heavy celestial body, either a stony asteroid, or (part of) an icy cometary nucleus. Against these interpretations speak (i) the absence of any secured debris, (ii) the almost radial treefall pattern with its five centers, and islands of survival, which is guided by the valleys, (iii) the 'telegraph poles', displaced root stumps, and heavy rocks near the epicenter, (iv) the heat felt in the faces of eyewitnesses (at 70 Km distance), (v) the four bright nights straddling the event, (vi) the reported chemical and isotopic anomalies which are reminiscent of outgassings, and (vii) its preferred geographical location, centered on the 250 Myr-old Kulikovskii crater, on several intersecting faultlines, and at extremes of the Siberian Moho, heat-flow, and magnetic-anomaly isohypses, not far from the craton's center. In view of the rareness of impact damages (at given energy) compared with tectonic damages - some 3% - I favour its interpretation as a (supersonic) ejection of some 10 Mton of natural gas, i.e. the present-day formation of a kimberlite. Search for references 226, 227, 236, 237, 249. Also: The 1908 Tunguska catastrophe: An alternative explanation (.pdf version), Tunguska (1908) and its relevance for comet/asteroid impact statistics (.pdf version), www.science-explorer.de/tunguska02.htm.
		The Hearts of the Plants Plants absorb ground water from the soil via capillary and osmotic suction, and force it up into their branches and leaves, again via these two types of forces. This nutritional supply - to heights which can reach 140 m (for redwoods, and eucalypti) - requires a reverse osmosis (for the available osmotic concentrations) which has been found to be exerted near the inner edge of the cortex of young rootlets, in their root-hair zone, when the sap enters the central cylinder, through the cylindrical sheet of endodermis and pericycle cells. Here beat the hearts of the plants, and dilute the incoming, osmotically pressurized stream by injecting pure water through hundreds of desmotubuli per cell wall - the membrane-crossing tubes of vacuoles connecting neighbouring cells - forced by embracing actin spirals with their attached myosin-VIII motors. They build up the well-known, time-variable root pressure (of 10 bar) which pushes the sap, allows roots to penetrate into the (rocky) ground, and drives guttation. Search for references 204, 217, 234, 247, 250. The water circuit of the plants: do plants have hearts?
		Quantization Classical and quantal systems are more analogous to each other than is commonly made evident, due to historical notation. The structure of fundamental physics is much more universal and elegant than is widely noticed. Search for references 256. Fundamental Physics (.pdf version)