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Il rifrattore acromatico Cauchoix, da 16 cm di apertura, acquisito dall'Osservatorio Astronomico del Collegio Romano nel 1825, è stato uno strumento fondamentale nella storia dell'astrofisica. Infatti nella seconda metà dell'800 Angelo Secchi, accoppiandolo col prisma obiettivo, lo utilizzò per ottenere la prima classificazione spettrale delle stelle. Installato su una nuova montatura equatoriale nel 1885 il telescopio è rimasto in servizio fino al 1980, quando fu smantellato. Recentemente abbiamo ritrovato il suo obiettivo di cui si erano perse le tracce per più di trent'anni. Questo ritrovamento ha permesso di ricostruire la configurazione meccanica e ottica dello strumento così come era al tempo di Secchi. Il telescopio è oggi esposto presso l'Osservatorio Astronomico di Roma a Monte Porzio Catone.

dalla Conferenza Nazionale dei Presidi di Scienze e Tecnologie e dalla Confindustria, è nato nel 2004 con l’obiettivo di incrementare il numero di immatricolazioni ai corsi di laurea in Chimica, Fisica, Matematica e Scienze dei materiali. Il nostro Ateneo partecipa al piano fin dal suo avvio per le aree di Fisica e Matematica. Nell’ambito del PLS in questi anni sono profondamente maturate le idee a riguardo delle problematiche relative all’orientamento e si è passati da una prospettiva di orientamento informativo a quella dell’orientamento formativo più profondamente connesso con la funzione educativa della Scuola e dell’Università e con la formazione dei docenti. Questo processo di maturazione è avvenuto sia a livello del coordinamento nazionale del progetto (MIUR, Conferenza dei Presidi), che a quello locale (Atenei, Dipartimenti, Scuole). Nel seguito illustrerò alcuni aspetti essenziali dello stato attuale del progetto in particolare per quanto riguarda l’area di Fisica, ulteriori dettagli potranno essere trovati nelle pagine web dedicate ai PLS di Matematica e Fisica

In a big town where the night sky is virtually invisible and if often only a virtual experience a telescope is the best channel for the real sky. Even a small telescope. Moon, planets, double stars and some deep sky objects become real objects viewed through an eyepiece or by means of modern CCD In the last few years, in the nice location of our Astrogarden, we did a lot of public outreach and educational activities using small telescopes. Our results show that these activities are very efficient in the broadening of understanding of astronomy and science with the public, in stimulating scientific interests with the young people and in developing useful skills in university students.

Angelo Secchi è universalmente ritenuto uno dei padri fondatori dell’Astrofisica per aver formulato la prima classificazione spettrale e grazie ai suoi studi sulla struttura dell’atmosfera e cromosfera solare. Per inquadrare il suo contributo alla fondazione della nuova scienza, illustreremo brevemente i contenuti dei suoi trattati: L’Unità delle Forze Fisiche, testo che delinea la sua visione scientifica, Le Stelle e Le Soleil, opere di contenuto propriamente astrofisico. A questi lavori vanno aggiunte le due memorie Sugli Spettri Prismatici delle Stelle Fisse e i contributi pubblicati nella letteratura scientifica nazionale ed internazionale dell’epoca.3

Many astronomical observatories where early astrophysical research was carried out have lost their original site or have changed their use. In Europe, the astrophysical observatories of Potsdam and Meudon are still used as astrophysical observatories, but their historical heritage (instruments, books and archives) are dispersed while the South Kensington Solar Observatory in London is no more extant, having being embodied in the buildings of the Science Museum. In Italy, the two different cases of Rome and Palermo observatories are here examined: the original site of the Collegio Romano Observatory, where fr. Angelo Secchi carried out his remarkable studies on stellar and solar spectroscopy, is now impossible to visit and its collections are splitted into two parts, one being kept at the Copernican and Astronomical Museum and the other one at the Monte Porzio Catone Observatory. The rooms of the Collegio Romano Observatory could be used for educational purposes, remarking the importance of recovering the original site and its historical importance. This has been done at the Palermo Observatory, still in use as an astrophysical observatory, where a historical museum has been installed in the original floor of the Observatory, keeping the instruments and the setting the nearest possible to their original arrangement.

The first permanent magnetic observatory in Italy was built in 1858 by Pietro Angelo Secchi, a Jesuit priest who made significant contributions in a wide variety of scientific fields, ranging from astronomy to astrophysics and meteorology. In this paper we consider his studies in geomagnetism, which have never been adequately addressed in the literature. We mainly focus on the creation of the magnetic observatory on the roof of the church of Sant'Ignazio, adjacent to the pontifical university, known as the Collegio Romano. From 1859 onwards, systematic monitoring of the geomagnetic field was conducted in the Collegio Romano Observatory, for long the only one of its kind in Italy. We also look at the magnetic instruments installed in the observatory, which were the most advanced for the time, as well as scientific studies conducted there in its early years.

Nelle pagine che seguono proponiamo una selezione di testi scritti dopo la morte di Angelo Secchi dai suoi estimatori, che possono aiutare a comprenderne meglio la figura scientifica ed umana. Come abbiamo visto nel precedente saggio di Rita Fioravanti, la bibliografia secchiana è immensa: non solo per il numero dei lavori scientifici, tecnici e didattici prodotti dal nostro scienziato, ma anche per la quantità di testi che fanno a lui riferimento.

Nonostante sia comunemente ritenuto da diversi studiosi (e.g. Meloni et al. 1997) che la fondazione del primo osservatorio magnetico in Italia risalga al 1880, in realtà la priorità spetta ad Angelo Secchi che a partire dal 1853 realizzò al Collegio Romano una stazione geomagnetica permanente. Nel seguito approfondiremo l’attività di Secchi nel campo della ricerca sul magnetismo terrestre. Dopo una descrizione della strumentazione magnetica allestita al Collegio Romano, mostreremo come egli avviò un sistematico lavoro di monitoraggio del campo geomagnetico e fu molto attento alla ricerca delle sue correlazioni con i fenomeni elettrici atmosferici. Concluderemo illustrando brevemente le misure ottenute a Roma in occasione della grande tempesta magnetica del 1859 passata alla storia come “Episodio di Carrington”.

On 1 Sep 1859 near the center of the solar disk the first-ever registered flare was detected in enhanced continuum emission in optical wavelengths (white light) by Carrington and Hodson. Moreover, it is the first-ever registered solar-geomagnetic event, which marked the beginning of space weather science. The Carrington flare produced a coronal mass ejection which after 17 hours triggered a giant geomagnetic storm. We present an analysis of this event performed on the basis of new historic geomagnetic data that we found in Italy (Rome) and geomagnetic data registered in Russia (St. Petersburg, Yekaterinburg, Barnaul, Nerchinsk). The value of the extreme magnetic disturbance registered on September 2, 1859 in Rome (~3000 nT) is the largest among the registered by other observatories. These observations are important in studying the Carrington solar-terrestrial event, since magnetic readings in all other world-wide observatories, except Colaba, went off scale. Variations of H-component registered at the Russian and Italian observatories are in very good accordance. In contrast to Colaba observations disturbances registered in all considered stations, including Rome, are positive, which is typical for auroral oval zone. During the severe magnetic disturbance, which is associated with the Carrington flare, its current system showed the character of a strongly asymmetric circuit that connected the partial ring current in the equatorial atmosphere to the current jet in the auroral zone, which was much shifted to the south relatively to it‟s usual location. It is supported by observation of an outstanding event in Rome - a spectacular aurora borealis in forms of streamers and columns of light. INTRODUCTION

The Italian national project Piano Lauree Scientifiche (PLS) is addressed to high school students in order to promote their interest in physics and science with the aim of increasing professional vocations and enrollments in scientific faculties. In the PLS framework, at Roma Tre University we developed an itinerant educational laboratory based on meteorites analysis by means of a portable kit. The activity is performed at school and the students are directly involved in the study of meteorite features and in measurements of physical properties of the samples. Students are intriguingly introduced in the scientific method working together in acquisition and analysis of data, and writing a final report. Lessons and laboratories were developed in collaboration between researchers and high school teachers. Thanks to their multidisciplinary character the activities represent an excellent tool for stimulating the interest in different fields of science as astronomy, physics, geology and biology. From a collection of meteorite samples we developed portable kits for a use in the schools. Siderite sections are dried by means of an evaporator, to prepare the samples for a protective coating. Thin sections of meteorite samples are also available for polarized light analysis. In our laboratory a set of instruments enables a multiparametric study of meteorites for both scientific and educational purposes. A 200-1000x microscope and a stereomicroscope are suited to the visual investigation of geological and structural features of meteorite samples. An UV/Vis/NIR spectrophotometer with integrating sphere enables transmission, absorbance and reflectance analysis; coupled with a cryostat, such instrumentation can reproduce thermodynamic conditions similar to the ones in the space. With the aim of such equipment intriguing hands-on activities and scientific researches can be performed on meteorite samples by means of non-destructive methods.

Nell’ultimo secolo e in particolare negli ultimi decenni l’Astronomia ha attraversato una fase di grande sviluppo che ha rivoluzionato la visione del Cosmo. Oggi il numero di studiosi di astrofisica è comparabile col numero degli astronomi che hanno operato nel corso di tutta la storia dell’umanità. La mole di informazione scientifica sugli oggetti celesti attualmente disponibile in tutte le bande dello spettro elettromagnetico è talmente grande da costituire ormai un vero e proprio Universo digitale a disposizione di tutti attraverso i progetti Virtual Observatory promossi da diverse agenzie internazionali. Una forte esigenza di maggiore consapevolezza del Cosmo emerge oggi più che mai dalla società, in particolare dal mondo della formazione e della scuola. Per questi motivi l’anno 2009, quattrocentesimo anniversario delle prime osservazioni al telescopio di Galileo, con le quali ha avuto idealmente inizio l’avventura della Scienza moderna, è stato proclamato Anno Internazionale dell’Astronomia (International Year of Astronomy - IYA2009) [ con il motto “L’Universo, a te scoprirlo”. Gli obiettivi IYA2009 possono essere brevemente così riassunti: - Diffondere più ampiamente la conoscenza scientifica; - Promuovere l’accesso alle nuove conoscenze e alle osservazioni astronomiche; - Rafforzare le comunità astronomiche nei paesi in via di sviluppo; - Promuovere la formazione scientifica formale ed informale; - Presentare un’immagine moderna della Scienza e degli scienziati; - Facilitare la nascita di nuove reti scientifiche, didattiche, amatoriali; - Migliorare la rappresentatività delle donne nelle carriere scientifiche; - Salvaguardare il patrimonio culturale rappresentato dai luoghi astronomici di interesse storico; - Sensibilizzare il pubblico sull’impoverimento culturale causato dall’inquinamento luminoso che nei paesi più sviluppati ha cancellato la visione del cielo stellato. Tutti questi temi costituiscono opportunità per la formazione dei più giovani, per l’educazione permanente degli adulti (Long Life Learning) e per la diffusione del sapere scientifico nell’attuale società della conoscenza . Un discorso sulla figura di Angelo Secchi si colloca pienamente sul solco di questi obiettivi in quanto egli ha avuto una profonda consapevolezza del complesso cammino della Scienza e del ruolo l’Astronomia svolge nella società.

Negli anni più recenti è emersa una forte esigenza di collaborazione didattica tra la scuola ed il mondo della ricerca, finaTizzataa lla formazione scientifica ed alla promozione dell'interessee della motivazione dei giovani verso le scienze. A livello europeo, sono numerosi i progetti significativi che riguardano sia la Fisica sia le altre Scienze Naturali. Molte di queste esperienze sono progettate erealizzate in collaborazione tra docenti delle scuole e delle università, studiosi degli enti di ricerca e comunicatori che operano nei musei scientifici. Tia queste iniziative si inseriscono i campi scuola residenzlali di Fisica organizzati ogni anno dall'Università Roma Tie al Museo del Balì. Lesperienza dei Campi Scuola, rivolta agli studenti del quarto o del quinto anno della scuola secondaria superiore, è stata awiata nel 2007 nel contesto del Progetto Nazionale Lauree Scientifiche

The Oriented World Globe (or Parallel Globe) is a common terrestrial globe whose axis is inclined with respect to horizontal plane at an angle equal to the latitude of the site (for Roma approximately 42°) and oriented along the meridian. I this way the axis will point towards North Celestial Pole, N.P. (Fig. 1) and will result parallel to the terrestrial axis. Placing the line of the meridian of the site represented on the globe map in coincidence with the true local meridian, the globe will show in real time the pattern of illumination of the Earth’s surface and its diurnal and seasonal variations. Since the terrestrial radius is negligible respect to the Earth-Sun distance, with good approximation we can consider the globe to be placed in the centre of the Celestial Sphere. Nevertheless such a Ptolemaic view, the globe turns out to be an ideal tool for a modern interdisciplinary teaching and meaningful learning of Astronomy, Geometry, Mathematics, Physics and Natural Sciences. For this reason small oriented world globe are commonly used in educational activities at school. The globe located in the centre of the Chiostro garden of the Physics Department E. Amaldi has been designed following the criteria recently proposed in the field of Architecture (Bozic et al. 2005) on the possible direct educational role of the indoor and outdoor spaces of schools and universities when these are arranged according to the principles of hands-on experiments.

The main lines of a collaboration developed at the Universities of Bologna, Milano-Bicocca, Napoli, Roma-Tre, Roma-Sapienza, Torino will be presented. The research continues the National Project F21 (“Teaching and learning pathways in Physics for the 21th century, in both ‘formal’ and ‘informal’ education”, 2004-2007), coordinated by P. Guidoni, whose objective was to improve and to refine a model for physics teaching, able to support understanding and motivation since early descriptive approaches to progressively more formal ones - including quantitative competence in selected themes of classical physics and non trivial understanding of modern physics insights. The collaborative work will be discussed according to: a) its theoretical framework; b) the basic research choices that are orienteering studies aimed at addressing school problems in designing long (K-13) conceptual paths for physics understanding in interaction with mathematics and other subject matters (cross- curricula); c) the open problems, hypotheses and strategic lines characterizing the current development of the research. Particular emphasis will be given to the research approach we chose to address the problem of reconstructing the whole curriculum (K-13). And we propose, at the end, to re-think, revise and unify coherently the existent materials on the basis of some fundamental “Framing Ideas" of physical knowledge. Such ideas – SPACE, TIME, MATTER, STATE, PROCESS, INTERACTION – should act as basic, structuring categories whose meaning variance in the development of physics reflects the link between the growth of physical knowledge and the change of its transverse connections and internal organization. The development of the framing ideas, of their relationships, and of their effective structuring role, will be pursued and analyzed according to two privileged “Longitudinal Leading Themes”, in turn acting as central attractors in the progressive articulation of the physics competence: a) Physical Objects (material systems, fields, particles,...) and their Interactions; b) Space-time relationships (movement, propagation, transformations...).

Un insegnamento della fisica che attinga anche a modalità non formali può svolgere un ruolo chiave nella formazione dei futuri fisici e, in prospettiva, sulla percezione che la società ha della fisica. Tra gli elementi che caratterizzano l’apprendimento non formale, assume grande evidenza la centralità dell’aspetto sociale e cooperativo, che si fonda sulla qualità della relazione umana e sulla condivisione di spazi e tempi poco strutturati in un contesto adeguato. Viene qui presentata e discussa un’esperienza fondata su questi elementi, svolta nella primavera del 2007: un Campo Scuola di Fisica realizzato presso il Museo del Balì e inserito nel contesto del Progetto Lauree Scientifiche del Collegio Didattico di Fisica dell’Università Roma Tre.

In occasione dell'Anno Internazionale dell'Astronomia, viene discusso il ruolo di questa scienza nell'ambito dell'insegnamento significativo delle scienze naturali della matematice e della fisica e presentata un'ampia panoramica delle risorse educative attualmente disponibili. Sono anche illustrate alcune attività didattiche non formali svolte in collaborazione tra università, scuola e strutture museali.

Roma, 22-25 ottobre 2008

In the "Astro-Scienze" project selected topics of astronomy and astrophysics play a fundamental role in stimulating the pupils’ interest in all the scientific disciplines. The activities were jointly designed by university and school teachers and were monitored through questionnaires that contained both open and closed type questions. The quantitative analysis of the pupils’ answers to the closed questions, reported here, indicates that the project responded to the pupils’ inner motivations, which are widely considered to be of great importance for meaningful learning.

We mainly concentrate on the analysis of the high resolution observations of V1974 Cyg (about 140 spectra), which cover 200 days and 330 days of its post-outburst evolution in the SWP and LWP cameras, respectively, at a resolution of about 25km/s. The tables contain, in a sequence, the IUE camera and image number, the date of the observation, and the measured radial velocities in km/s. The laboratory vacuum wavelengths of the transitions considered are indicated. The labels "p" and "d" refer, respectively, to the principal and the diffuse-enhanced absorption systems. Blanks mean that no reliable radial velocity measurements could be obtained.

The World Space Observatory Project is a new space mission concept, grown out the needs of the Astronomical community to have access to the part of the electromagnetic spectrum where all known physics can be studied on all possible time scales: the Ultraviolet range. The physical diagnostics in this domain supply a richness of new experimental data unmatched by any other wavelength range, for the studies of the Universe. As WSO/UV has been driven by the needs of scientists from many different countries, a new implementation model was needed to bring theWorld Space Observatory to reality. The WSO/UV consists of a single Ultraviolet Telescope in orbit, incorporating a primary mirror of 1.7 m diameter feeding a UV spectrograph and UV Imagers.

We carry out an analysis of the Mg II 2796.34 Angstrom emission line in RS CVn stars and make a comparison with the normal stars studied in a previous paper ( Paper I). The sample of RS CVn stars consists of 34 objects with known HIPPARCOS parallaxes and observed at high resolution with IUE. We confirm that RS CVn stars tend to possess wider Mg II. lines than normal stars having the same absolute visual magnitude. However, we could not find any correlation between the logarithmic line width log W-o and the absolute visual magnitude M-V (the Wilson-Bappu relationship) for these active stars, contrary to the case of normal stars addressed in Paper I. On the contrary, we find that a strong correlation exists in the (M-V, log L-MgII) plane (L-MgII is the absolute flux in the line). In this plane, normal and RS CVn stars are distributed along two nearly parallel straight lines with RS CVn stars being systematically brighter by approximate to1 dex. Such a diagram provides an interesting tool to discriminate active from normal stars. We finally analyse the distribution of RS CVn and of normal stars in the (log L-MgII, log W-o) plane, and find a strong linear correlation for normal stars, which can be used for distance determinations.

We report a detailed study about the ripple correction and absolute calibration of IUE high resolution spectra processed with NEWSIPS (i.e. the IUE Final Archive processing scheme). The analysis, based on very many spectra obtained with the SWP, LWP and LWR cameras, shows that the empirical positions of the blaze peaks vary in a way which does not depend only on the spectrograph's optics, but also on the camera's spatial response. This latter has been successfully parametrized as a function of the camera head temperature for the SWP camera and of the observing date for the LWP and LWR cameras. The performance of the ripple correction algorithms so obtained represent an important improvement over the ones adopted for IUESIPS. The ripple corrected high resolution spectra were then used to derive a new high resolution absolute calibration, which is accurate to within 3-4%, all over the spectral range covered by the IUE cameras.

In this paper we study in detail the variability of the symbiotic nova AG Peg in the IUE range during the period 1978-1995. We find that the luminosity of the hot component decreased steadily from about 1850 L. in 1978 to 430 L. in 1995 while its effective temperature remained nearly constant, 86500 +/- 1300 degrees K. At the same time, the mass loss rate decreased by a factor of 4-5 although the ejection velocity remained constant. The observed fainting of both the narrow and the broad emission lines is ascribed to the decrease of the luminosity and ionizing flux from the hot source. The narrow emission lines and the long wavelength UV continuum show periodic variations arising from a dense and asymmetric nebular region associated with the cool star. Radial velocity variations of the narrow lines indicate that this region is receding from the center of mass of the system, and support the presence of the ablation tail suggested by Penston and Alien (1985). No periodic flux variations are seen in the short wavelength ultraviolet continuum and in the broad emission lines, which are both formed in the fast wind from the hot component.

We present the results of an extensive campaign of coordinated X-ray (ROSAT) and UV (IUE) observations of the symbiotic star AG Dra during a long period of quiescence (1990-1993) followed by two optical outbursts in 1994 and 1995. The hot component (i.e. X-ray emitting compact object) turns out to be very luminous during the quiescent phase: (9.5+/-1.5)*10^36 (D/2.5 kpc)^2 erg/s. This suggests that the compact object is burning hydrogen-rich matter on its surface even in the quiescent (as defined optically) state at a rate of (3.2+/-0.5)*10^-8 (D/2.5 kpc)^2 M_sun/yr. Assuming a steady state, i.e. burning at precisely the accretion supply rate, this high rate suggests a Roche lobe filling cool companion though Bondi-Hoyle accretion from the companion wind cannot be excluded. We have discovered a remarkable decrease of the X-ray flux during both optical maxima. In the UV these events were characterized by a large increase of the emission line and continuum fluxes. The anticorrelation of X-ray/UV flux and optical brightness evolution is very likely due to a temperature decrease of the hot component which could be the result of an increased mass transfer to the burning compact object, causing it to slowly expand to about twice its original size during each optical outburst., accepted for publ. in A&A, 17 pages incl. 5 Figs

We present the first Fourier Transform Spectrograph near-IR spectrum (0.95-2.5 mu m) of eta Car observed at CFHT in January 1987 with a resolution of 40-100 km s(-1). We have identified lines of H I (Paschen, Brackett series), He I, Fe II, [Fe III, [N I] with complex structures. At the time of these observations eta Car was in a low excitation phase characterized by a general weakening of the hydrogen lines, and with the He I lambda 1082.9 nm line much weaker than in 1990-91.

Following a previous study by Altamore et al. (1982, Paper I) of the ultraviolet spectrum of KQ Pup, and the spectral Atlas of this star by Altamore et al. (1991, Paper II), we analyze coude and CAT CES optical spectra of the object observed during 1969-1984, and compare with IUE data obtained in 1979. Besides the M-star photospheric absorptions, the optical spectrum shows sharp emissions of [S II], [Cu II], [Fe II], Fe II, and [Ni II]. They probably arise in an intermediate region of the M-star wind ionized by the hot star radiation, where also the P Cygni UV lines of ionized metals are formed. The region is more extended and closer to the M-star near periastron passage. The earlier Balmer lines present a double peaked emission with a sharp central absorption which in 1979 and 1983 appears double suggesting the presence of streams or clouds of matter in the system environment. The redshifted emission component disappears in the higher series members, giving rise to an inverse P Cygni profile. Some Balmer lines display very broad absorption components which are identified as the density broadened hot star photospheric lines. He I is probably present with a rotationally broadened absorption at 3819 angstrom largely hidden by the rich M-star spectrum. In the UV the resonance lines and the excited lines of the doubly ionized metals are broad and redshifted by about +37 km s-1 with respect to the M-star radial velocity, implying line formation in opaque and turbulent matter flowing near and towards the surface of the hot star. From the blue-IR colour indices and the 2200 angstrom interstellar band we derive for KQ Pup a colour excess of E(B-V) = 0.14 +/- 0.03. The ultraviolet to infrared energy distribution appears bimodal with the hot component dominating below about 3600 angstrom and the M star above 4000 angstrom. We have fitted the dereddened energy distribution with a combination of a 30 000 K black body and of a M-supergiant spectrum (alpha-Ori), and derived for KQ Pup a distance at 1400 +/- 200 pc. At this distance the hot component results a slightly underluminous BOV star with a radius of 4.35R.. The mass ratio of the components of the binary system seems to be close to unity. We propose for KQ Pup a binary model with a highly mass losing cool supergiant primary and an unevolved early-type secondary. The optical and UV emission lines are formed in the regions of the cool star wind which are ionized by the hot star radiation. A shock is probably produced near the hot star by the interaction of the cool star wind with the hot star wind. Instabilities probably occur near the shock which produce cool clouds from the M-star wind, which may penetrate the hot star wind and be accreted.