Royal Institute and Observatory of the Spanish Navy

About: Royal Institute and Observatory of the Spanish Navy is a facility organization based out in San Fernando, Spain. It is known for research contribution in the topics: Gamma-ray burst & Magnetic anomaly. The organization has 50 authors who have published 106 publications receiving 2565 citations. The organization is also known as: Instituto y Observatorio de Marina de San Fernando.

On Periodic Polar Orbits in the Artificial Satellite Problem

Abstract: We compute periodic orbits in the Artificial Satellite Theory. We fix our attention on the Earth case where we considered a zonal gravitational model for the potential. In a rotating frame attached to the Earth we have found sixteen polar orbits that are periodic after different number of revolutions. The altitude of each orbit remains almost constant and varies from about 263 km for the sixteen-revolutions orbit to about 35,830 km for the one-revolution orbit. All the orbits are linearly stable and their period is exactly 24 hours.

Monitoring the Solar Radius from the Royal Observatory of the Spanish Navy since 1773

Abstract: The solar diameter has been monitored at the Royal Observatory of the Spanish Navy (today the Real Instituto y Observatorio de la Armada: ROA) almost continuously since its creation in 1753 (i.e. during the past 250 years). After a painstaking effort to collect data in the historical archive of this institution, we present here the data of the solar semidiameter from 1773 to 2006, making up an extensive new database for solar-radius measurements, which can be considered. We have calculated the solar semidiameter from the transit times registered by the observers (except for values of the solar radius from the modern Danjon astrolabe, which were published by ROA). These data were analysed to reveal any significant long-term trends, but no such trends were found. Therefore, the data sample confirms the constancy of the solar diameter during the past 250 years (approximately) within instrumental and methodological limits. Moreover, no relationship between solar radius and the new sunspot-number index has been found from measurements of the ROA. Finally, the mean value for the solar semidiameter (with one standard deviation) calculated from the observations made in the ROA (1773 – 2006), after applying corrections for refraction and diffraction, is equal to $958.87^{\prime\prime}\pm1.77^{\prime\prime}$ .

The Calar Alto lunar occultation program: update and new results

Abstract: We present an update of the lunar occultation program which is routinely carried out in the near-IR at the Calar Alto Observatory. A total of 350 events were recorded since our last report (Fors et al. 2004). In the course of eight runs we have observed, among others, late-type giants, T-Tauri stars, and infrared sources. Noteworthy was a passage of the Moon close to the galactic center, which produced a large number of events during just a few hours in July 2004. Results include the determinations of the angular diameter of RZ Ari, and the projected separations and brightness ratios for one triple and 13 binary stars, almost all of which representing first time detections. Projected separations range from 0. '' 09 to 0. '' 007. We provide a quantitative analysis of the performance achieved in our observations in terms of angular resolution and sensitivity, which reach about 0. '' 003 and K � 8.5mag, respectively. We also present a statistical discussion of our sample, and in particular of the frequency of detection of binaries among field stars.

A GPS calibration trip experience between ROA and PTB

Abstract: For a GPS calibration campaign between ROA and PTB a GTR50 time and frequency transfer receiver from ROA was chosen. The operation performance of GTR50 type receivers has been validated in long term operation during the last years. The travelling GTR50 was also tested in a sequence of shutdowns and restarts to detect time jumps and malfunctions just after the restart and during the following days of operation.