Search Publications
Turbulence in the Inner Solar Wind Determined from Frequency Fluctuations of the Downlink Signals from the ULYSSES and GALILEO Spacecraft
Plettemeier, D.; Bird, M. K.; Efimov, A. I. +2 more
The results of several sets of measurements of the frequency of radio signals during coronal-sounding experiments carried out from 1991 to 2000 using the ULYSSES and GALILEO spacecraft are presented and analyzed. The S-band signals (carrier frequency f = 2295 MHz) were received at the three 70-m widely spaced ground stations of the NASA Deep Space…
The 3-D shaping of NGC 6741: A massive, fast-evolving Planetary Nebula at the recombination-reionization edge
Sabbadin, F.; Turatto, M.; Cappellaro, E. +2 more
We infer the gas kinematics, diagnostics and ionic radial profiles, distance and central star parameters, nebular photo-ionization model, spatial structure and evolutionary phase of the Planetary Nebula NGC 6741 by means of long-slit ESO NTT+EMMI high-resolution spectra at nine position angles, reduced and analysed according to the tomographic and…
The proper motion of the Magellanic Clouds: The UCAC2-Hipparcos inconsistency
Momany, Y.; Zaggia, S.
Using the USNO CCD Astrograph all-sky Catalog (UCAC2), we measure the mean proper motion of the two Magellanic Clouds. Appropriately-selected LMC populations show a proper motion <µα,µδ>≃(+0.84,+4.32) that is significantly higher, in <µδ>, than currently accepted Hipparcos-like values; <µα,µδ>≃(+1.94…
Determination of confusion noise for far-infrared measurements
Lemke, D.; Klaas, U.; Kiss, Cs.
We present a detailed assessment of the far-infrared confusion noise imposed on measurements with the ISOPHOT far-infrared detectors and cameras aboard the ISO satellite. We provide confusion noise values for all measurement configurations and observing modes of ISOPHOT in the 90 µm ≤ λ ≤ 200 µm wavelength range. Based on these results…
CLASS B0631+519: last of the Cosmic Lens All-Sky Survey lenses
Pearson, T. J.; McKean, J. P.; Blandford, R. D. +13 more
We report on the discovery of the new gravitational lens system CLASS B0631+519. Imaging with the Very Large Array, the Multi-Element Radio-Linked Interferometer Network (MERLIN) and the Very Long Baseline Array (VLBA) reveals a doubly imaged flat-spectrum radio core, a doubly imaged steep-spectrum radio lobe and possible quadruply imaged emission…
Out of the darkness: the infrared afterglow of the INTEGRAL burst GRB 040422 observed with the VLT
Covino, S.; D'Avanzo, P.; Campana, S. +15 more
Investigating the EGRET-radio galaxies link with INTEGRAL: The case of 3EG J1621+8203 and NGC 6251
Guainazzi, M.; Grenier, I. A.; Grandi, P. +10 more
The analysis of an INTEGRAL AO2 observation of the error contours of the EGRET source 3EG J1621+8203 is presented. The only source found inside the error contours for energies between 20 and 30 keV at 5σ detection significance is the FR I radio galaxy NGC 6251. This supports the identification of NGC 6251 with 3EG J1621+8203. The observed flux is …
Photographic observations of solar system bodies at the Engelhardt astronomical observatory
Rizvanov, N.; Nefedjev, Ju.
We describe a large database of photographic observations of Solar System bodies obtained at the Engelhadt Astronomical Observatory (EnAO). We give a brief description of the methods of observations and the accuracy of their reduction with the PPM and Tycho-2 catalogues. The photographic positions of the major planets, except Jupiter, are in the s…
Proper Motion of the Irradiated Jet HH 399 in the Trifid Nebula
Yusef-Zadeh, F.; Wardle, M.; Biretta, J.
HH 399 is one of the first Herbig-Haro flows recognized to be irradiated by the UV radiation of the massive O7.5 star in the Trifid Nebula. We present the proper motion of the first irradiated jet, based on two epochs of Hubble Space Telescope (HST) observations of HH 399 separated by nearly 5 yr, using Hα and [S II] line filters. High proper moti…
The Beagle 2 stereo camera system
Coates, A. J.; Josset, J. -L.; Pillinger, C. T. +6 more
The stereo camera system (SCS) was designed to provide wide-angle multi-spectral stereo imaging of the Beagle 2 landing site. Based on the Space-X micro-cameras, the primary objective was to construct a digital elevation model of the area in reach of the lander's robot arm. The SCS technical specifications and scientific objectives are described; …