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37
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Introduction
Additional affiliations
September 2012 - November 2012
October 2005 - December 2015
September 2010 - October 2012
Publications
Publications (37)
Orbiting space objects have become in the last decade a major nuisance impacting ground astronomy and orbiting space assets, from observatories to satellites and space stations. In particular with the rise of the satellite population in Low Earth Orbits, space objects are becoming an even bigger threat and a strong problem to astronomical observati...
Orbiting space objects have become in the last decade a major nuisance impacting ground astronomy and orbiting space assets, from observatories to satellites and space stations. In particular with the rise of the satellite population in Low Earth Orbits (LEOs), space objects are becoming an even bigger threat and a strong problem to astronomical ob...
Maneuvering a spacecraft in the cislunar space is a complex problem, since it is highly perturbed by the gravitational influence of both the Earth and the Moon, and possibly also the Sun. Trajectories minimizing the needed fuel are generally preferred in order to decrease the mass of the payload. A classical method to constrain maneuvers is mathema...
The increasing amount of space debris poses a significant threat to operational satellites and space-based services. This article updates the community on the current status of the development of ATLAS, a tracking radar that is part of the EUSST network and aims to detect space objects in low Earth orbits. This article focuses on the latest activit...
The growing population of man-made objects with the build up of mega-constellations not only increases the potential danger to all space vehicles and in-space infrastructures (including space observatories), but above all poses a serious threat to astronomy and dark skies. Monitoring of this population requires precise satellite characterization, w...
As part of the Portuguese Space Surveillance and Tracking (SST) program, a tracking radar and a double Wide Field of View Telescope system (4.3{\deg} x 2.3{\deg}) are being installed at the Pampilhosa da Serra Space Observatory (PASO) in the centre of continental Portugal, complementing an already installed deployable optical sensor for MEO and GEO...
The ever increasing dependence of modern societies in space based services results in a rising number of objects in orbit which grows the probability of collisions between them. The increase in space debris is a threat to space assets, space based-operations and led to a common effort to develop programs for dealing with it. As part of the Portugue...
The Electron Proton and Alpha Monitor (EPAM) onboard the Advanced Composition Explorer (ACE) spacecraft detected a Solar Energetic Particle Event (SEP) on 2015 October 29. The EPAM telescopes detected near relativistic electrons, and protons with energies above 1 GeV. Although no statistically significant enhancement in the count rates of neutron m...
On 2017 September 10, the neutron detectors on the Earth's surface detected the second Ground Level Enhancement (GLE) of the solar cycle 24. This GLE was associated with a beam-like near relativistic electron event seen by the Electron, Proton, and Alpha Monitor (EPAM) particle instrument in the Advanced Composition Explorer (ACE). All the electron...
Astrotourism and related citizen science activities are becoming a major trend of a sustainable, high-quality tourism segment, core elements to the protection of Dark skies in many countries. In the Summer of 2020, in the middle of COVID pandemics, we started an initiative to train young students - Cyber-Cosmos - using an Unistellar eVscope, a smar...
O período entre 2018 e 2022 mostrou-nos que o problema dos incêndios à escala global não está a diminuir, antes pelo contrário. Parece que as consequências das alterações climáticas já estão a afectar a ocorrência de incêndios florestais em várias partes do Mundo, de uma forma que só esperaríamos que acontecesse vários anos mais tarde. Em muitos pa...
The increase in space debris is a threat to space assets, space based-operations and led to a common effort to develop programs for dealing with this increase. As part of the Portuguese Space Surveillance and Tracking (SST) project, led by the Portuguese Ministry of Defense (MoD), the Instituto de Telecomunica\c{c}\~oes (IT) is developing rAdio TeL...
Astrotourism and related citizen science activities are becoming a major trend of a sustainable, high-quality tourism segment, core elements to the protection of Dark skies in many countries. In the Summer of 2020, in the middle of COVID pandemics, we started an initiative to train young students - Cyber-Cosmos - using an Unistellar eVscope, a smar...
Radio astronomy and Space Infrastructures in the Azores have a great scientific and industrial interest because they benefit from a unique geographical location in the middle of the North Atlantic allowing a vast improvement in the sky coverage. This fact obviously has a very high added value for: i) the establishment of space tracking and communic...
As part of the Portuguese Space Surveillance and Tracking (SST) System, two new Wide Field of View (2.3deg x 2.3deg) small aperture (30cm) telescopes will be deployed in 2021, at the Pampilhosa da Serra Space Observatory (PASO), located in the center of the continental Portuguese territory, in the heart of a certified Dark Sky area. These optical s...
ATLAS is the first Portuguese radar system that aims to detect space debris. The article introduces the system and provides a brief description of its capabilities. The system is capable of synthesizing arbitrary amplitude modulated pulse shapes with a resolution of 10 ns. Given that degree of freedom we decided to test an amplitude modulated chirp...
Radio astronomy and Space Infrastructures in the Azores have a great scientific and industrial interest because they benefit from a unique geographical location in the middle of the North Atlantic allowing a vast improvement in the sky coverage. This fact obviously has a very high added value for: i) the establishment of space tracking and communic...
Currently, space debris represents a threat for satellites and space-based operations, both in-orbit and during the launching process. The yearly increase in space debris represents a serious concern to major space agencies leading to the development of dedicated space programs to deal with this issue. Ground-based radars can detect Earth orbiting...
Currently, space debris represents a threat for satellites and space-based operations, both in-orbit and during the launching process. The yearly increase in space debris represents a serious concern to major space agencies leading to the development of dedicated space programs to deal with this issue. Ground-based radars can detect Earth orbiting...
sDOPPLER is a funded project aimed to provide training in STEM for students and teachers, using robotics in non-formal education. In the Mozambican context, it also works as a lobby in order to accelerate important curricula changes that must be achieved, so that schools can put aside the theoretical approach they use and adopt new forms of teachin...
A general architecture for collection and processing of water resources data, in terms of quality and quantity, is presented and discussed. The proposed architecture includes the sensing of physical and chemical water parameters, data communications, and high levels of information processing, namely machine learning. The architecture adopts an Inte...
As the largest radio telescope in the world, the Square Kilometre Array (SKA) will lead the next generation of radio astronomy. The feats of engineering required to construct the telescope array will be matched only by the techniques developed to exploit the rich scientific value of the data. To drive forward the development of efficient and accura...
This white book stems from the contributions presented at the Portuguese SKA Days, held on the 6th and 7th February 2018 with the presence of the SKA Deputy Director General Alistair McPherson and the SKA Science Director Robert Braun. This initiative was held to promote the Square Kilometer Array (SKA) - the world's largest radio telescope - among...
As the largest radio telescope in the world, the Square Kilometre Array (SKA) will lead the next generation of radio astronomy. The feats of engineering required to construct the telescope array will be matched only by the techniques developed to exploit the rich scientific value of the data. To drive forward the development of efficient and accura...
The detailed knowledge of the Milky Way radio emission is important to characterize galactic foregrounds masking extragalactic and cosmological signals. The update of the global sky models describing radio emissions over a very large spectral band requires high sensitivity experiments capable of observing large sky areas with long integration times...
Background
We describe the design, the construction and performance of a narrow band ortho-mode transducer, currently used in the 5 GHz polarimetric receiver of the Galactic Emission Mapping project. ResultsThe ortho-mode transducer was designed to achieve a high degree of transmission within the 400 MHz of the GEM band around the 5 GHz (4.8–5.2 GH...
The Mozambique Radio Astronomy Observatory (MRAO) will be a first milestone
towards development of radioastronomy in Mozambique. Development of MRAO will
constitute a preparation step towards participation in the upcoming Africa VLBI
Network and the Square Kilometer Array project. The MRAO first antenna is
planned to serve as a capacitation and tra...
The paper describes the project, implementation and test of a C-band (5GHz)
Low Noise Amplifier (LNA) using new low noise Pseudomorphic High Electron
Mobility Transistors (pHEMTS) from Avago. The amplifier was developed to be
used as a cost effective solution in a receiver chain for Galactic Emission
Mapping (GEM-P) project in Portugal with the obj...
In the context of the Galactic Emission Mapping, a new receiver at 5GHz was developed to characterize the galactic foreground to the Cosmic Microwave Background Radiation. This is a 5GHz super heterodyne polarimeter with double down conversion, with a high gain IF chain using the latest RF technology working at 600MHz central frequency that feeds a...
The international Galactic Emission Mapping project aims to map and characterize the polarization field of the Milky Way. In Portugal it will cartograph the C-band sky polarized emission of the Northern Hemisphere and provide templates for map calibration and foreground control of microwave space probes like ESA Planck Surveyor mission. The receive...
not required Comment: not published
In the context of the Galactic Emission Mapping collaboration, a galactic survey at 5GHz is in preparation to properly characterize the galactic foreground to the Cosmic Microwave Background Radiation (CMBR). For the North sky survey, a new receiver is being developed. This 5GHz heterodyne polarimeter has a high gain IF (intermediate frequency) cha...
In the context of the Galactic Emission Mapping collaboration, a new receiver at 5GHz is being developed to characterize the galactic foreground to the Cosmic Microwave Background Radiation.. This is a 5GHz heterodyne polarimeter with a high gain IF chain using the latest RF technology working at 600MHz central frequency that feeds a four channel d...
In the context of the new era of Cosmic Microwave Background Polarization (CMBP) experiments, it is important to have reliable templates of the polarized foregrounds contaminating the CMBP. This is specially true for the for the Planck Surveyor Mission (ESA, 2007) and for the near-future B-mode polarization probes. The Galactic Emission Mapping col...
The Galactic Emission Mapping collaboration is proceeding towards the survey of the polarized emission at 5GHz of the whole sky from antennas located in Portugal -covering the North Hemisphere -and Brazil -covering the South Hemisphere. The obtained maps will be used in the subtraction and component separation of the galactic foreground emission to...