The NASA/DLR Stratospheric Observatory for Infrared Astronomy (SOFIA), a 2.5-meter infrared telescope on board a Boeing 747-SP, will conduct 0.3 - 1,600 μm photometric, spectroscopic, and imaging observations from altitudes as high as 45,000 ft., where the average atmospheric transmission is greater than 80 percent. SOFIA's first light cameras and spectrometers, as well as future generations of instruments, will make important contributions to the characterization of the physical properties of exoplanets. Our analysis shows that optical and near-infrared photometric and spectrophotometric follow-up observations during planetary transits and eclipses will be feasible with SOFIA's instrumentation, in particular the HIPO-FLITECAM optical/NIR instruments. The airborne-based platform has unique advantages in comparison to ground- and space-based observatories in this field of research which we will outline here. Furthermore we will present two exemplary science cases, that will be conducted in SOFIA's cycle 1.

Recent theoretical studies on Traveling Interplanetary Phenomena (TIP) and their relation or presumed relation to their solar origins will be reviewed. An attempt is made to outline the theoretical studies in the context of mathematical methods and physical processes. The following alternative approaches are examined: analytical vs. numerical methods; magnetohydrodynamics vs. hydrodynamics; processes with or without dissipation; continuum (macroscopic) vs. the kinetic (microscopic) approach. In particular, the flare-generated interplanetary shocks are used as examples to illustrate these theoretical studies within the context of TIP. Some emphasis will be placed on MHD wave propagation through the inner corona and its maturity to a fully-developed interplanetary shock. Further, their propagation and the disturbing effects on the solar wind will be considered. Cases concerning the classification and characteristics of blast-produced shocks and long-lasting ejecta are also discussed in the context of numerical simulations.

This paper reviews the links currently envisaged for a mission of duration 3½ years, with estimates of the precision of each link.

The results of a spectrum synthesis analysis of elemental abundances derived from the high-resolution CCD-spectrograms of the SMC red supergiant stars PMMR23 and PMMR39 (stars 23 & 39 in the catalogue Prevot et al. 1983) are presented. The abundances of 35 elements in the atmosphere of PMMR23 have been obtained. Elements with atomic numbers Z<56 are deficient with respect to the solar abundances. The mean underabundance is about –0.7 dex. The abundances of elements heavier than barium are close to the solar value. In the case of PMMR23, the atmosphere is enriched in elements heavier than barium which show abundances close to the solar value. These abundances can be explained as a combination of r- and s-processes. In PMMR39, all the 20 studied elements present abundances deficient with respect to solar values The abundances of 31 elements with Z>30 are determined in the atmosphere of Arcturus.

We give a brief overview of where we stand with respect to some old and new questions bearing on how massive stars evolve and end their lifetime. We focus on the following key points that are further discussed by other contributions during this conference: convection, mass losses, rotation, magnetic field and multiplicity. For purpose of clarity, each of these processes are discussed on its own but we have to keep in mind that they are all interacting between them offering a large variety of outputs, some of them still to be discovered.

We give here a detailed description of the latest INPOP planetary ephemerides INPOP20a. We test the sensitivity of the Sun oblateness determination obtained with INPOP to different models for the Sun core rotation. We also present new evaluations of possible GRT violations with the PPN parameters β, γ and . With a new method for selecting acceptable alternative ephemerides we provide conservative limits of about 7.16 × 10-5 and 7.49 × 10-5 for β-1 and γ-1 respectively using the present day planetary data samples. We also present simulations of Bepi-Colombo range tracking data and their impact on planetary ephemeris construction. We show that the use of future BC range observations should improve these estimates, in particular γ. Finally, interesting perspectives for the detection of the Sun core rotation seem to be reachable thanks to the BC mission and its accurate range measurements in the GRT frame.

New developments in surface flux transport modeling and theory of flux transport dynamos have given rise to the notion that certain large active regions with anomalous properties (location, tilt angle and/or Hale/non-Hale character) may have a major impact on the course of solar activity in subsequent years, impacting also on the amplitude of the following solar cycles. Here we discuss our current understanding of the role of such “rogue” active regions in cycle-to-cycle variations of solar activity.

The kinematics and dynamics of prominence eruptions are reviewed and different phases of the eruption are identified. The properties of the equation of motion in these phases are shown. The morphology of the prominence prior and during the eruption is described and the implications to the MHD description of the process are discussed.

High dispersion spectra in the visible range were obtained for field Be Stars in both hemispheres. As Be Stars form a class of Main Sequence fast rotators, we are intended to test how their chemical composition can be affected by rotation.

It is shown that the absorption due to a circumstellar shell containing solid silicon carbide particles can very nicely explain the observed strong violet opacity in stars in which the carbon to oxygen ratio is > 1. It has been shown by Friedemann and Gilman that solid SiC particles can form in the cooler outer layers of such stars. Thermal re-emission from SiC particles is predicted to be in the 10–13 μ region and recent infrared observations by Hackwell show an emission band in this region, thereby strongly supporting the SiC suggestion. It is also shown that the opacity due to C3 pseudo-continuum is not adequate to explain the observed violet opacity.

It is suggested that the vibrational bands of C3 and SiC2 molecules should be among the major opacity sources in the infrared spectra of the late N-type carbon stars and some of the observed bands may be, at least in part, due to these molecules. The frequencies of their isotopic species have been calculated and attempts should be made to observe these bands.

I Zw 1 is a well-known narrow-line quasar with very strong Fe II emission. High S/N spectra obtained with the HST FOS show a remarkably rich emission-line spectrum. The C III*λ1176 line is clearly detected in emission for the first time in AGNs. This line arises from radiative decay to the 2s2p3Pº0,1,2 metastable levels of C III. The observed flux is ~ 50 times larger than expected from collisional excitation or dielectronic recombination in photoionized gas. The most plausible mechanism for the large enhancement in the C III* λ1176 flux is resonance scattering of continuum photons by C III* ions. This mechanism requires large velocity gradients (~ 1000 km s−1) within each emitting cloud in the BLR. Such large velocity gradients can be induced by forces external to the gas in the BLR clouds, such as tidal disruption, or radiation pressure.

A narrow-band translator and filter system has been constructed for the Parkes Multibeam receiver. This brief note outlines the characteristics of the system and indicates the range of new projects that will be possible in studies of the Magellanic Clouds.

The conclusion by Maeder et al.(1980) that the strong gradient in NR/NWR results from the effect of metal content on the rate of mass loss is reconsidered. We suggest that the above gradient simply reflects a simi lar gradient in the progenitor stars, although effects of metallicity cannot be excluded.

As part of an on-going study of radio transients in Epoch 1 (2017–2019) of the Very Large Array Sky Survey (VLASS), we have discovered a sample of 0.2 < z < 3.2 active galactic nuclei (AGN) selected in the optical/infrared that have recently brightened dramatically in the radio. These sources would have previously been classified as radio-quiet based on upper limits from the Faint Images of the Radio Sky at Twenty-centimeters (FIRST; 1993-2011) survey; however, they are now consistent with radio-loud quasars. We present a quasi-simultaneous, multi-band (1–18 GHz) VLA follow-up campaign of our sample of AGN with extreme radio variability. We conclude that the radio properties are most consistent with AGN that have recently launched jets within the past few decades, potentially making them among the youngest radio AGN known.

We present results of the analysis of spectroscopic time-series observations of the roAp star HD 24712 obtained at the phase of magnetic maximum. As in previous investigations of roAp stars we found that only lines of the rare-earth elements (REE) show RV pulsational variations. These pulsations in HD 24712 are characterised by gradual phase shifts between RV curves of different REE. The same pulsations of HD 24712 were observed in 2001, giving strong evidence for the stability of the pulsational mechanism in this star. NLTE calculations of Nd line depth formation in stratified atmosphere of HD 24712 allowed us to study the pulsational phase distribution with optical depth, providing strong evidence for a running wave, propagating outward with nearly constant RV amplitude.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

The BIPM/IAU Joint Committee on relativity for space-time reference systems and metrology (JCR) has worked in collaboration with the IAU Working Group on relativity for celestial mechanics and astrometry (RCMA) on the problems of astronomical relativistic space-time reference frames and the RCMA has proposed to the IAU a consistent framework for defining the barycentric and geocentric celestial reference systems at the first post-Newtonian level. Because new clock technology and space missions will necessitate the application of this framework for time and frequency measurements in the solar system, practical resolutions are proposed by the JCR to the IAU to allow a consistent treatment of these measurements. The paper outlines the conclusions of the work which resulted in the proposed IAU resolutions.

Many areas of extragalactic research will greatly benefit from observations with a very large telescope. We concentrate, here, on four of them as illustrative examples:

First we briefly discuss the study of the absorption lines in quasar spectra.

In the second section we suggest the possibility of doing serendipity large field imaging during high spectral resolution exposures on point sources.

In sections 3 and 4 we discuss two topics which have long been recognized as important drivers for the construction of very large telescopes, the determination of the nature of the missing mass, and the study of elliptical galaxies.

Carignan et al. (C06, 2006, ApJ, 641, L109) recently presented an extended HI rotation curve (RC) of M31, using single dish observations from the 100m Effelsberg and Green Bank telescopes. These data were obtained along the semi-major axis of the approaching half of the M31 HI disk and showed a flat RC at large radius, which extends up to ~35 kpc (using D = 780 kpc). The kinematical analysis of M31 is pursued here and new deep 21cm observations obtained at the Dominion Radio Astrophysical Observatory (DRAO) are presented. A tilted-ring model is fitted to a new HI velocity field, allowing the derivation of the position angle P.A. and inclination i as a function of radius. We concentrate on the approaching half of the disk in order to compare our new results with those from C06. It is shown that the disk warping of M31 does not severely contaminate the kinematics of the neutral gas. As a consequence, the RC from C06 is in very good agreement with the new derived RC.

Debris disks are usually thought to be gas-poor, the gas being dissipated by accretion or evaporation during the protoplanetary phase. HD141569A is a 5 Myr old star harboring a famous debris disk, with multiple rings and spiral features. I present here the first PdBI maps of the 12CO(2−1), 13CO(2−1) gas and dust emission at 1.3 mm in this disk. The analysis reveals there is still a large amount of (primordial) gas extending out to 250 AU, i.e. inside the rings observed in scattered light. HD141569A is thus a hybrid disk with a huge debris component, where dust has evolved and is produced by collisions, with a large remnant reservoir of gas.

The dynamic transient gamma-ray sky is revealing many interesting results, largely due to findings by Fermi and Swift. The list includes new twists on gamma-ray bursts (GRBs), a GeV flare from a symbiotic star, GeV flares from the Crab Nebula, high-energy emission from novae and supernovae, and, within the last year, a new type of object discovered by Swift—a jetted tidal disruption event. In this review we present highlights of these exciting discoveries. A new mission concept called Lobster is also described; it would monitor the X-ray sky at order-of-magnitude higher sensitivity than current missions can.