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In the context of current and future microwave surveys mainly dedicated to the accurate mapping of Cosmic Microwave Background (CMB), mm and sub-mm emissions from Solar System will represent a potential source of contamination as well as an opportunity for new Solar System studies. In particular, the forthcoming ESA Planck mission will be able to observe the point-like thermal emission from planets and some large asteroids as well as the diffused Zodiacal Light Emission (ZLE). After a brief introduction to the field, we focus on the identification of Solar System discrete objects in the Planck time ordered data.

This paper aims to describe the Pointing Reconstruction Model (PRM) and the prototype Star Tracker, which will be mounted on LSPE-Strip, a microwave Q- and W-band CMB telescope planned for installation at the \"Observatorio del Teide\" in Tenerife. The PRM integrates information on the instantaneous attitude provided by the telescope control system to determine the actual pointing direction and focal plane orientation of the telescope. It accounts for various non-idealities in the telescope setup, represented by eight configuration angles, which will be calibrated using the Star Tracker. Following the derivation of the PRM formalism and its implementation, we investigate the pointing errors caused by incorrect calibration of these configuration angles to validate the required 1 arcminute maximum systematic pointing error for the LSPE-Strip survey. This paper also describes the main structure and operations of the Star Tracker and presents the results of a campaign of actual sky observations conducted with a prototype. The results demonstrate a Star Tracker RMS accuracy of approximately 3 arcseconds, while systematic errors remain below 10 arcseconds. Based on these results, we analyzed the problem of reconstructing the PRM configuration angles. Two methods for intercalibrating the Star Tracker's pointing direction with respect to the focal plane's pointing direction were examined: (1) observations of planets and (2) observations of a drone carrying both an optical beacon and a radio beacon. In the first case, an intercalibration accuracy between 1/3 arcminute and 1 arcminute is achievable. In the second case, the expected intercalibration accuracy ranges from 0.25 arcminute to 1 arcminute.

We present new estimates of the brightness temperatures of Jupiter, Saturn, Uranus, and Neptune based on the measurements carried in 2009--2013 by PLANCK/LFI at 30, 44, and 70 GHz and released to the public in 2018. This work extends the results presented in the 2013 and 2015 PLANCK/LFI Calibration Papers, based on the data acquired in 2009--2011. PLANCK observed each planet up to eight times during the nominal mission. We processed time-ordered data from the 22 LFI radiometers to derive planet antenna temperatures for each planet and transit. We accounted for the beam shape, radiometer bandpasses, and several systematic effects. We compared our results with the results from the ninth year of WMAP, PLANCK/HFI observations, and existing data and models for planetary microwave emissivity. For Jupiter, we obtain Tb = 144.9, 159.8, 170.5 K (+/- 0.2 K at 1 sigma, with temperatures expressed using the Rayleigh-Jeans scale) at 30, 44 and 70 GHz, respectively, or equivalently a band averaged Planck temperature TbBA=144.7$, 160.3, 171.2 K in good agreement with WMAP and existing models. A slight excess at 30 GHz with respect to models is interpreted as an effect of synchrotron emission. Our measures for Saturn agree with the results from WMAP for rings Tb = 9.2 +/- 1.4, 12.6 +/- 2.3, 16.2 +/- 0.8 K, while for the disc we obtain Tb = 140.0 +/- 1.4, 147.2 +/- 1.2, 150.2 +/- 0.4 K, or equivalently a TbBA=139.7, 147.8, 151.0 K. Our measures for Uranus (Tb = 152 +/- 6, 145 +/- 3, 132.0 +/- 2 K, or TbBA=152, 145, 133 K and Neptune Tb = 154 +/- 11, 148 +/- 9, 128 +/- 3 K, or TbBA=154 , 149, 128 K) agree closely with WMAP and previous data in literature.

We present EOS, a procedure for determining the Outgoing Longwave Radiation (OLR) and top-of-atmosphere (TOA) albedo for a wide range of conditions expected to be present in the atmospheres of rocky planets with temperate conditions. EOS is based on HELIOS and HELIOS-K, which are novel and publicly available atmospheric radiative transfer (RT) codes optimized for fast calculations with GPU processors. These codes were originally developed for the study of giant planets. In this paper we present an adaptation for applications to terrestrial-type, habitable planets, adding specific physical recipes for the gas opacity and vertical structure of the atmosphere. To test the reliability of the procedure we assessed the impact of changing line opacity profile, continuum opacity model, atmospheric lapse rate and tropopause position prescriptions on the OLR and the TOA albedo. The results obtained with EOS are in line with those of other RT codes running on traditional CPU processors, while being at least one order of magnitude faster. The adoption of OLR and TOA albedo data generated with EOS in a zonal and seasonal climate model correctly reproduce the fluxes of the present-day Earth measured by the CERES spacecraft. The results of this study disclose the possibility to incorporate fast RT calculations in climate models aimed at characterizing the atmospheres of habitable exoplanets.

This article aims to highlight the impact for ground based astronomical observations in different windows of the electromagnetic spectrum coming from the deployment of fleets of telecommunications satellites. A particular attention is given to the problem of crowding of circumterrestrial space by medium/small size orbiting objects. Depending on their altitude and surface reflectivity, their contribution to the sky brightness is not negligible for professional ground based observations. With the huge amount of about 50,000 new artificial satellites for telecommunications planned to be launched in Medium and Low Earth Orbit, the mean density of artificial objects will be of >1 satellite for square sky degree; this will inevitably harm professional astronomical images leaving trails on them. Only one of these project, Starlink@SpaceX's, authorized by US Federal Communication Commission, plans to deploy about 42,000 not geostationary satellites, which will shine in sky after sunset and before sun dawn. Satellites will be observed in deep field images and particularly negative for scientific large area images used to search for Near Earth Objects, predicting and, eventually, avoiding possible impact events. Serious concerns are also common to other wavelengths eligible for ground based investigation, in particular for radio-astronomy, whose detectors are already saturated by the ubiquitous irradiation of satellites communication from Space stations as well as from the ground. The risk of running into the \"Kessler syndrome\" is also noteworthy. Understanding the risk for astronomical community, a set of actions are proposed in this paper to mitigate and contain the most dangerous effects arising from such changes in the population of small satellites. A dedicate strategy for urgent intervention to safeguard and protect each astronomical band observable from the ground is outlined.

Despite decades of scientific research on the subject, the climate of the first 1.5 Gyr of Mars history has not been fully understood yet. Especially challenging is the need to reconcile the presence of liquid water for extended periods of time on the martian surface with the comparatively low insolation received by the planet, a problem which is known as the Faint Young Sun (FYS) Paradox. In this paper we use ESTM, a latitudinal energy balance model with enhanced prescriptions for meridional heat diffusion, and the radiative transfer code EOS to investigate how seasonal variations of temperature can give rise to local conditions which are conductive to liquid water runoffs. We include the effects of the martian dichotomy, a northern ocean with either 150 or 550 m of Global Equivalent Layer (GEL) and simplified CO\\(_2\\) or H\\(_2\\)O clouds. We find that 1.3-to-2.0 bar CO\\(_2\\)-dominated atmospheres can produce seasonal thaws due to inefficient heat redistribution, provided that the eccentricity and the obliquity of the planet are sufficiently different from zero. We also studied the impact of different values for the argument of perihelion. When local favorable conditions exist, they nearly always persist for \\(>15\\%\\) of the martian year. These results are obtained without the need for additional greenhouse gases (e.g. H\\(_2\\), CH\\(_4\\)) or transient heat-injecting phenomena (e.g. asteroid impacts, volcanic eruptions). Moderate amounts (0.1 to 1\\%) of CH\\(_4\\) significantly widens the parameter space region in which seasonal thaws are possible.

The Large Scale Polarization Explorer (LSPE) project, funded by the Italian Space Agency (ASI), includes the development of LSPE-Strip, a ground-based radio telescope for observing Cosmic Microwave Background (CMB) anisotropies. LSPE-Strip, nearing its construction phase, will operate from the Teide Observatory in Tenerife, employing 49 coherent polarimeters at 43 GHz to deliver critical data on CMB anisotropies and 6 channels at 95 GHz as atmospheric monitor. On-site characterization of such advanced instruments is crucial to detect possible systematic effects, such as gain fluctuations, beam distortions, and pointing errors, that can compromise performance by introducing spurious polarizations or radiation collection from unintended directions. To address these challenges, a drone-mounted Q-band test source for on-site characterization of LSPE-Strip's polarimeter array was developed. Modern Unmanned Aerial Vehicles (UAVs) offer a flexible approach for antenna pattern measurements, yet their use in high-frequency radio astronomy is not consolidated practice. In October 2022, a UAV-based measurement campaign was conducted with the TFGI instrument on the second QUIJOTE telescope in Tenerife, in collaboration with the Instituto de Astrofisica de Canarias. This pioneering effort aimed to validate UAV-based beam characterization methods and assess QUIJOTE's performance under operational conditions. Preliminary results demonstrated high measurement accuracy, leveraging QUIJOTE's dual-receiver configuration for beam validation. These findings provide valuable insights for optimizing UAV systems in preparation for LSPE-Strip's future characterization.

In the context of current and future microwave surveys mainly dedicated to the accurate mapping of Cosmic Microwave Background (CMB), mm and sub-mm emissions from Solar System will represent a potential source of contamination as well as an opportunity for new Solar System studies. In particular, the forthcoming ESA Planck mission will be able to observe the point-like thermal emission from planets and some large asteroids as well as the diffused Zodiacal Light Emission (ZLE). After a brief introduction to the field, we focus on the identification of Solar System discrete objects in the Planck time ordered data.

We report on time series photometry of the faint Neptune irregular satellite Neso. Observations in the V, R, and I pass-bands were performed in photometric conditions at the Cerro Paranal observatory using the instrument FORS2, in the night of July 15th, 2010. Astrometry and photometry derived from these observations are presented here. The time coverage of about six hours does not allow to construct a light curve and derive a meaningful rotational period. However, we could derive new estimates of apparent magnitudes obtaining R=25.2 pm 0.2 mag in agreement with Brozovic, Jacobson, Sheppard (2011), and also V=25.6 pm 0.3 mag, and I=24.5 pm 0.3. In this way we could derive for the first time Neso colors, V-I=1.0 pm 0.4 mag, R-I=0.7 pm 0.4 mag and V-R=0.3 pm 0.4 mag. We compared those colors with those in Peixinho, Delsanti, Doressoundiram (2015). The color R-I appears to be slightly redder than the typical values for Centaurs and KBOs, the color V-I is in nice agreement with both populations. The large error-bars prevents from assigning Neso to any of the reference classes, just looking at Neso colors, although the data seem to suggest that we can rule out its membership in classes of resonant objects or Plutinos.

Both Centaurs and trans-Neptunian objects (TNOs) are minor bodies found in the outer Solar System. Centaurs are a transient population that moves between the orbits of Jupiter and Neptune, and they probably diffused out of the TNOs. TNOs move mainly beyond Neptune. Some of these objects display episodic cometary behaviour; a few percent of them are known to host binary companions. Here, we study the light-curves of two Centaurs -2060 Chiron (1977 UB) and 10199 Chariklo (1997 CU26)- and three TNOs -38628 Huya (2000 EB173), 28978 Ixion (2001 KX76), and 90482 Orcus (2004 DW)- and the colours of the Centaurs and Huya. Precise, ~1%, R-band absolute CCD photometry of these minor bodies acquired between 2006 and 2011 is presented; the new data are used to investigate the rotation rate of these objects. The colours of the Centaurs and Huya are determined using BVRI photometry. The point spread function of the five minor bodies is analysed, searching for signs of a coma or close companions. Astrometry is also discussed. A periodogram analysis of the light-curves of these objects gives the following rotational periods: 5.5+-0.4 h for Chiron, 7.0+-0.6 h for Chariklo, 4.45+-0.07 h for Huya, 12.4+-0.3 h for Ixion, and 11.9+-0.5 h for Orcus. The colour indices of Chiron are found to be B-V=0.53+-0.05, V-R=0.37+-0.08, and R-I=0.36+-0.15. The values computed for Chariklo are V-R=0.62+-0.07 and R-I=0.61+-0.07. For Huya, we find V-R=0.58+-0.09 and R-I=0.64+-0.20. We find very low levels of cometary activity (if any) and no sign of close or wide binary companions for these minor bodies.