Related papers: The Heliometer of Rio de Janeiro in Operation - 20…
Started its regular, daily operational phase in 2011 and installed in 2009 by the occasion of the Symp264 in the XXVII IAU GA at Rio de Janeiro, the results so far obtained show that the Heliometer of the Observatorio Nacional fulfilled its…
Out of the three quantities that characterize the state of an isolated gaseous body: pressure, temperature and volume the radius is the only one directly measurable for the Sun, what is specially true in the optical window and for ground…
Monitoring the micro-variations of the solar diameter helps to better understand local and secular trends of solar activity and Earth climate. The instant measurements with the Reflecting Heliometer of Observatorio Nacional in Rio de…
The heliometer of Fraunhofer in Koenigsberg (1824) is a refractor in which the lens is split into two halves to which is applied a linear displacement along the cut. Later in 1890s a variation of the heliometer has been realized in…
This work presents the development and construction of the Heliometer of the Observat\'orio Nacional/MCTI. This instrument is designed to monitor changes on the solar diameter with the accuracy of the next-generation solar satellites. A…
Recent research on global climate changes points to three distinct sources of climate disturbance: anthropogenic; natural changes in the oceans and atmosphere; and irregularities in the solar cycles. One of the most direct ways to survey an…
The solar astrolabe at Observatorio Nacional has been doing a series of solar semidiameter measurements, extending from 1998 up to 2009, to a total of 21640 observations of the Sun. Using the data series it was established the solar radius…
From 1998 to 2003 the CCD Solar Astrolabe of the Observatorio Nacional in Rio de Janeiro made more than 20000 observations of the Solar Semidiameter. In the present work similar corrections for the observational results of 2002 and 2003…
This work has aimed to analyze the 1998 to 2000 campaign of solar diameter surveying. The employed instrument was a Danjon astrolabe, at the Observat\'orio Nacional campus, and specially modified for the solar observations. During the time…
From 1997 the Observatorio Nacional has been observing the Sun with an astrolabe in order to study variations on the solar semi-diameter. Till now more than 20.000 observations were done. The observations taken in the year of 2001 were…
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 confirmed in the case of the Earth, and after the intrinsic solar…
The Astronomical Observatory of the University of Coimbra has a huge collection of solar images, acquired daily since 1926. From the beginning, only spectroheliograms in the CaiiK line has been recorded, and since 1989 in the H_alpha line…
Robo-AO is the first autonomous laser adaptive optics system and science instrument operating on sky. With minimal human oversight, the system robotically executes large scale surveys, monitors long-term astrophysical dynamics and…
The prototype Robo-AO system at the Palomar Observatory 1.5-m telescope is the world's first fully automated laser adaptive optics instrument. Scientific operations commenced in June 2012 and more than 12,000 observations have since been…
At Pic du Midi observatory we carry out a solar survey with images of the photosphere, prominences and corona. This survey, named CLIMSO (CLIch\'es Multiples du SOleil), is in the following spectral lines: Fe XIII corona (1.075 micron),…
We present an analysis of polarimetric observations of standard stars performed over the period of more than three years with the RINGO3 polarimeter mounted on the Liverpool Telescope. The main objective was to determine the instrumental…
Full-disk spectroheliograms have been taken in Coimbra on a daily basis since 1926 in the Ca II K-line (K1 and K3). Later, in 1989, with the upgrade of the equipment it was possible to start the observations in the H-alpha line. The…
The X-Ray Telescope (XRT) onboard the Hinode satellite, launched 23 September 2006 by the Japanese Aerospace Exploration Agency (JAXA) is a joint mission between Japan, the United States, and the United Kingdom to study the solar corona. In…
The calibration of weather radar for detecting meteorological phenomena has advanced rapidly, aiming to enhance accuracy. Utilizing an unmanned aerial vehicle (UAV) equipped with a suspended metal sphere introduces an efficient calibration…
HERA is a highly-redundant transit interferometer with 14\,m-diameter parabolic dish elements. We exploit the fact that the Galactic centre transits through the main beam of the telescope to attempt a conventional self-calibration approach…