Search Publications
Discovery of Far-Infrared Pure Rotational Transitions of CH+ in NGC 7027
Barlow, M. J.; Cernicharo, J.; González-Alfonso, E. +4 more
We report the discovery of the rotational spectrum of CH+ in the Infrared Space Observatory Long Wavelength Spectrometer (LWS) spectrum of the planetary nebula NGC 7027. The identification relies on a 1996 reanalysis of the LWS spectrum by Liu et al. and on new LWS data. The strong line at 179.62 µm (coinciding with the 212
WFPC2 Observations of the Carina Dwarf Spheroidal Galaxy.
Mighell, Kenneth J.
We present our analysis of Hubble Space Telescope Wide Field Planetary Camera 2 observations in F555W (∼V) and F814W (∼I) of the Carina dwarf spheroidal galaxy. The resulting V vs V-I color-magnitude diagrams reach V≈27.1 mag. The reddening of Carina is estimated to be E(V-I)=0.08±0.02 mag. A new estimate of the distance modulus of Carina, (m - M)…
The Asymmetric Radio Remnant of SN 1987A
Gaensler, B. M.; Manchester, R. N.; Staveley-Smith, L. +3 more
We present seven years of radio observations of SN 1987A made with the Australia Telescope Compact Array. At 1.4, 2.4, 4.8, and 8.6 GHz, the flux density of the radio remnant has increased monotonically since emission was redetected 1200 days after the explosion. On day 3200, the remnant was expanding at 2800 +/- 400 km s-1, which we in…
HST/GHRS Observations of the Compact Slow Ejecta of Eta Carinae
Humphreys, R. M.; Balick, B.; Davidson, Kris +6 more
We report spectroscopic observations of eta Car and adjacent gas with an unprecedented combination of spatial and spectral resolution, 0.1 arcsec x 0.1 Angstroms. Radial velocities show that the bright objects C and D, 0.2 arcsec from the star, are slow equatorial ejecta. The narrow emission lines which fluctuate in the spectrum of the core region…
Globular cluster orbits based on Hipparcos proper motions
Tucholke, H. -J.; Brosche, P.; Odenkirchen, M. +1 more
We present and analyse space motions and orbits for a sample of 15 galactic globular clusters. The absolute proper motions of these clusters have been determined with respect to reference stars of the new Hipparcos system. Orbital integrations in two model potentials for the Galaxy are considered.
The sample shows a mean rotation near 40 km s…Solar wind stream interfaces in corotating interaction regions: SWICS/Ulysses results
Wimmer-Schweingruber, Robert F.; von Steiger, Rudolf; Paerli, Raoul
Motivated by the well-known differences in charge state and even elemental composition of the slow solar wind as compared to high-speed streams, we have analyzed observations made by the Solar Wind Ion Composition Spectrometer (SWICS)/Ulysses mass spectrometer of the series of corotating interaction regions (CIRs) encountered by Ulysses in 1992/19…
HST and Infrared Images of the Circumstellar Environment of the Cool Hypergiant IRC + 10420
Smith, Nathan; Humphreys, Roberta M.; Davidson, Kris +6 more
We present HST WFPC2 and ground-based infrared images of the very evolved, luminous OH/IR star IRC+10420. The HST optical images reveal an amazingly complex environment, with one or more distant reflection shells probably ejected during the star's previous red supergiant stage plus numerous features within two arcseconds of the star including cond…
Hubble Space Telescope Observations of Two Dynamically Young Elliptical Galaxies
Whitmore, Bradley C.; Fall, S. Michael; Miller, Bryan W. +1 more
High-resolution images of the candidate dynamically young ellipticals NGC 1700 and NGC 3610 have been obtained with the WFPC2 of the Hubble Space Telescope. NGC 1700 contains approximately a dozen dust clouds arranged in a chaotic distribution near the center of the galaxy, suggestive of a merger or accretion event. NGC 3610 contains a remarkably …
Separate Lightcurves of Pluto and Charon
Buie, Marc W.; Wasserman, Lawrence H.; Tholen, David J.
We present new Hubble Space Telescope observations of the Pluto-Charon system taken with WFPC1 (PC6) between 1992 May 21 and 1993 August 18. Our observations consist of 52 images with the F555W filter and 8 images in the F439W filter. From these data we extracted individual lightcurves, phase coefficients, and colors for Pluto and Charon. These li…
A massive black hole at the centre of the quiescent galaxy M32
van der Marel, Roeland P.; Rix, Hans-Walter; de Zeeuw, P. Tim +1 more
Massive black holes are thought to reside at the centres of many galaxies1,2, where they power quasars and active galactic nuclei. But most galaxies are quiescent, indicating that any central massive black hole present will be starved of fuel and therefore detectable only through its gravitational influence on the motions of the surroun…