• Publications
  • Influence
Deuterium in the Galactic Centre as a result of recent infall of low-metallicity gas
It is concluded that the observed Galactic Centre deuterium is cosmological, with an abundance reduced by stellar processing and mixing, and that there is no significant Galactic source ofDeuterium.
Size and albedo of Kuiper belt object 55636 from a stellar occultation
Observations of a multi-chord stellar occultation by KBO 55636, which occurred on 9 October 2009, find that it has a mean radius of 143 ± 5 km and a geometric albedo of in the V photometric band, which establishes that KBO55636 is smaller than previously thought and that, like its parent body, it is highly reflective.
Limb Spicules from the Ground and from Space
We amassed statistics for quiet-sun chromosphere spicules at the limb using ground-based observations from the Swedish 1-m Solar Telescope on La Palma and simultaneously from NASA’s Transition Region
Changes in Pluto’s Atmosphere: 1988-2006
The 2006 June 12 occultation of the star P384.2 (2UCAC 26039859) by Pluto was observed from five sites in southeastern Australia with high-speed imaging photometers that produced time-series CCD
Short-Period Waves That Heat the Corona Detected at the 1999 Eclipse
As a part of a study of the cause of solar coronal heating, we searched for high-frequency (∼ 1 Hz) intensity oscillations in coronal loops in the [Fe xiv] coronal green line. We summarize results
High-frequency oscillations in the corona observed at the 1983 eclipse
We detected excess oscillatory power at 0.25–2.0 Hz in a coronal loop in the 1983 Indonesian total solar eclipse. In this second-generation experiment enlarging upon the work of Pasachoff and Landman
The recent expansion of Pluto's atmosphere
Observations at a variety of visible and infrared wavelengths of an occultation of a star by Pluto in August 2002 reveal evidence for extinction in Pluto's atmosphere and show that it has indeed changed, having expanded rather than collapsed, since 1988.
Charon's radius and atmospheric constraints from observations of a stellar occultation
Multiple-station observations of a stellar occultation by Charon are reported and results seem to be consistent with collisional formation for the Pluto–Charon system in which the precursor objects may have been differentiated, and they leave open the possibility of atmospheric retention by the largest objects in the outer Solar System.
Molecular Line Observations and Chemical Modelling of Edge Cloud 2
Edge Cloud 2 (EC2) is a molecular cloud, about 35 pc in size, with one of the largest galactocentric distances known to exist in the Milky Way. We present observations of a peak CO emission region in
High-frequency coronal oscillations and coronal heating
At the 1980 total solar eclipse, we searched for high-frequency (0.1–2 Hz) oscillations in the intensity of the 5303-Å coronal green line, as a test of predictions of theories of coronal heating via