68 citations · 268 across the 12 of their papers we have counts for
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Parallaxes of southern extremely cool objects III: 118 L \& T dwarfs
R. L. Smart, B. Bucciarelli, H. R. A. Jones +17
We present new results from the Parallaxes of Southern Extremely Cool dwarfs program to measure parallaxes, proper motions and multi-epoch photometry of L and early T dwarfs. The o…
42 Years of Continuous Observations of the Solar Diameter from 1974 to 2015
Alexandre H. Andrei, Sergio C. Boscardin, Jucira L. Penna +2
Several group in the World followed the solar diameter with dedicated instruments, namely solar astrolabes, since 1974. Their data have been gathered in several observing stations…
The solar diameter series of the CCD Solar Astrolabe of the Observatório Nacional in Rio de Janeiro measured during cycle 23
Costantino Sigismondi, Sergio Calderari Boscardin, Alexandre Humberto Andrei +3
The interest on the solar diameter variations has been primary since the scientific revolution for different reasons: first the elliptical orbits found by Kepler in 1609 was confir…
Parallaxes of Southern Extremely Cool objects (PARSEC) II: Spectroscopic Follow-up and Parallaxes of 52 Targets
F. Marocco, A. H. Andrei, R. L. Smart +8
We present near-infrared spectroscopy for 52 ultracool dwarfs, including two newly discovered late-M dwarfs, one new late-M subdwarf candidate, three new L and four new T dwarfs. W…
NPARSEC: NTT Parallaxes of Southern Extremely Cool objects. Goals, targets, procedures and first results
R. L. Smart, C. G. Tinney, B. Bucciarelli +21
The discovery and subsequent detailed study of T dwarfs has provided many surprises and pushed the physics and modeling of cool atmospheres in unpredicted directions. Distance is a…
Development and first year of results from the heliometer of Observatorio Nacional
Alexandre H. Andrei, Victor A. D'Avila, Eugenio Reis Neto +5
Recent research on global climate changes points to three distinct sources of climate disturbance: anthropogenic; natural changes in the oceans and atmosphere; and irregularities i…