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The Survey of the MAgellanic Stellar History (SMASH; [1]) was designed to study in depth the two largest satellites of the Milky Way, the Magellanic Clouds. This survey, with the Dark Energy Camera (DECam; which is funded mainly by the US Department of Energy), mapped 480 square degrees (distributed over 2,400 square degrees in and around the Clouds) in five photometric bands (ugriz) down to magnitude ~24 in each band. All of the observations were released in SMASH DR2 [2] and are available via NOIRLab’s Astro Data Lab. Although the observations were collected during the period 2013–2016, the SMASH collaboration continues exploiting the rich dataset. We report here three new exciting results from the survey.

Understanding the evolutionary history of the Magellanic Clouds requires an in-depth exploration and characterization of the stellar content in their outer regions, which ultimately are key to tracing the epochs and nature of past interactions. We present new deep images of a shell-like over-density of stars in the outskirts of the Small Magellanic Cloud (SMC). The shell, also detected in photographic plates dating back to the fifties, is located at ~1.9 degr from the center of the SMC in the north-east direction.The structure and stellar content of this feature were studied with multi-band, optical data from the Survey of the MAgellanic Stellar History (SMASH) carried out with the Dark Energy Camera on the Blanco Telescope at Cerro Tololo Inter-American Observatory. We also investigate the kinematic of the stars in the shell using the Gaia Data Release 2. The shell is composed of a young population with an age ~ 150 Myr, with no contribution from an old population. Thus, it is hard to explain its origin as the remnant of a tidally disrupted stellar system. The spatial distribution of the young main-sequence stars shows a rich sub-structure, with a spiral arm-like feature emanating from the main shell and a separated small arc of young stars close to the globular cluster NGC 362. We find that the absolute g-band magnitude of the shell is M_{g,shell} = -10.78+/- 0.02, with a surface brightness of mu_{g,shell} = 25.81+/- 0.01 mag/arcsec^{2}. We have not found any evidence that this feature is of tidal origin or a bright part of a spiral arm-like structure. Instead, we suggest that the shell formed in a recent star formation event, likely triggered by an interaction with the Large Magellanic Cloud and/or the Milky Way, ~150 Myr ago., Comment: 16 pages, 14 figures, submitted to Astronomy & Astrophysics

The Nearby Magellanic Clouds system covers 180 square degrees on the sky. Much of it has been mapped across the electromagnetic spectrum at high angular resolution and sensitivity –X-ray (XMM-Newton), UV (UVIT), optical (SMASH), IR (VISTA, WISE, Spitzer, Herschel), radio (ATCA, ASKAP, MeerKAT). This provides us with an excellent dataset to explore the galaxy populations behind the stellar-rich Magellanic Clouds. We seek to identify and characterise AGN via machine learning algorithms on this exquisite data set. Our project focusses not on establishing sequences and distributions of common types of galaxies and active galactic nuclei (AGN), but seeks to identify extreme examples, building on the recent accidental discoveries of unique AGN.

We present a method to map the total intrinsic reddening of the Small Magellanic Cloud (SMC) via the analysis of spectral energy distributions (SEDs) of background galaxies covering the wavelength range 0.3-2.5 micron. Using the LePhare chi^2 minimisation SED-fitting routine and various samples of galaxies and/or quasi-stellar objects, we find that, only when we create reddening maps using objects with low levels of intrinsic reddening, the resulting maps are consistent with previous literature determinations i.e. regions such as the Bar and Wing show elevated levels of reddening compared to other regions in the SMC. We have tested the dependency on the adopted templates and find that theoretical templates imply significantly higher levels of reddening by up to 0.15 mag in E(B-V). A comparison with existing literature reddening maps -- based on the stellar components of the SMC -- shows a reasonable level of agreement, however significant discrepancies are also observed which could highlight appreciable levels of dust not accounted for in the stellar reddening maps and are likely attributable to the different tracers sampling different lengths along the line-of-sight dust column.

The One Thousand and One Magellanic Fields (1001MC) survey aims to measure the kinematics and elemental abundances of many different stellar populations that sample the history of formation and interaction of the Magellanic Clouds. The survey will collect spectra of about half a million stars with G < 19.5 magnitudes (Vega) distributed over an area of about 1000 square degrees and will provide an invaluable dataset for a wide range of scientific applications., Published in The Messenger vol. 175, pp. 54-57, March 2019.

The 32 Ori moving group was discovered almost a decade ago and despite the fact that it represents thefirst northern, young (~20 Myr) stellar aggregate within 100 pc of the Sun, a comprehensive characterisationof the stellar content of the group has yet to be performed. We hereby present the first large-scalespectroscopic survey for new (predominantly low-mass K- and M-type) members of the 32 Ori moving groupafter combining kinematic and photometric data to select candidate members with Galactic space motionand positions in colour-magnitude space consistent with group membership. Final memberships are assignedon the basis of a combination of radial velocity, Hα emission and Li absorption diagnostics. Weidentify ~25 new members, thereby increasing the number of known 32 Ori moving group members by a factorof ~3. Finally, we demonstrate consistent ages for the group based on isochronal fitting in thecolour-magnitude diagram and the location of the Li depletion boundary. This consistency suggests thatthe group is essentially coeval with the Beta Pictoris moving group with an age in the range 20-25 Myr.In the era of SPHERE, GPI, ALMA, etc. this group therefore represents a benchmark region for direct-imagingstudies of circumstellar disc evolution (especially during the epoch of terrestrial planet formation) and,of course, extrasolar planets.

In this contribution I will discuss fundamental stellar parameters as determined from young star clusters; specifically those with ages less than or approximately equal to that of the Pleiades. I will focus primarily on the use of stellar evolutionary models to determine the ages and masses of stars, as well as discuss the limitations of such models using a combination of both young clusters and eclipsing binary systems. In addition, I will also highlight a few interesting recent results from large on-going spectroscopic surveys (specifically Gaia-ESO and APOGEE/IN-SYNC) which are continuing to challenge our understanding of the formation and early evolutionary stages of young clusters., Comment: 11 pages, Proceedings of the 19th Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun, 2016, Uppsala, Sweden, G. A. Feiden ed

The vesicular stomatitis virus phosphoprotein, NS, was the subject of this investigation. Multiple forms of NS protein were identified in Piry infected cells. These multiple species were demonstrated to be related by comparative peptide mapping under conditions of complete or partial digestion. Furthermore, kinetic studies revealed that one of the NS forms (NSᵢ) could be converted into a mature NS form (NSᵥ) by a covalent post-translational modification. The nature of this modification was investigated using inhibitors of both phosphorylation and acetylation. NS protein isolated from cells infected with the Indiana serotype was structurally characterized by a variety of techniques including enzymatic digestion, chemical cleavage and partial acid hydrolysis. The observations presented here indicate that NS exists under denaturing conditions as a monomer and is post-translationally modified by multisite phosphorylation. NS isolated from infected cells appears to be phosphorylated toward the amino terminus of the polypeptide primarily in one large tryptic peptide. Monospecific antisera were raised against SDS-polyacrylamide gel purified Indiana virion proteins. These sera were used to investigate viral protein aggregates in both virions and infected cells. In particular it was demonstrated that a protein kinase activity capable of in vitro phosphorylation of NS protein could be identified in immunoprecipitates of NS protein. The significance of these findings with respect to other published observations is discussed. Doctor of Philosophy (PhD)

The current status of and motivation for the 4MOST survey strategy, as developed by the Consortium science team, are presented here. Key elements of the strategy are described, such as sky coverage, number of visits and total exposure times in different parts of the sky, and how to deal with different observing conditions. The task of organising the strategy is not simple, with many different surveys that have vastly different target brightnesses and densities, sample completeness levels, and signal-to-noise requirements. We introduce here a number of concepts that we will use to ensure all surveys are optimised. Astronomers who are planning to submit a Participating Survey proposal are strongly encouraged to read this article and any relevant 4MOST Survey articles in this issue of The Messenger such that they can optimally complement and benefit from the planned surveys of the 4MOST Consortium., Published in The Messenger vol. 175, pp. 17-21, March 2019.

The 4MOST instrument is a multi-object spectrograph that will address Galactic and extragalactic science cases simultaneously by observing targets from a large number of different surveys within each science exposure. This parallel mode of operation and the survey nature of 4MOST require some distinct 4MOST- specific operational features within the overall operations model of ESO. The main feature is that the 4MOST Consortium will deliver, not only the instrument, but also contractual services to the user community, which is why 4MOST is also described as a facility. This white paper concentrates on information particularly useful to answering the forthcoming Call for Letters of Intent., Published in The Messenger vol. 175, pp. 12-16, March 2019.

We introduce the 4-metre Multi-Object Spectroscopic Telescope (4MOST), a new high-multiplex, wide-field spectroscopic survey facility under development for the four-metre-class Visible and Infrared Survey Telescope for Astronomy (VISTA) at Paranal. Its key specifications are: a large field of view (FoV) of 4.2 square degrees and a high multiplex capability, with 1624 fibres feeding two low-resolution spectrographs (R = λ/Δλ ~ 6500), and 812 fibres transferring light to the high-resolution spectrograph (R ~ 20 000). After a description of the instrument and its expected performance, a short overview is given of its operational scheme and planned 4MOST Consortium science; these aspects are covered in more detail in other articles in this edition of The Messenger. Finally, the processes, schedules, and policies concerning the selection of ESO Community Surveys are presented, commencing with a singular opportunity to submit Letters of Intent for Public Surveys during the first five years of 4MOST operations., Published in The Messenger vol. 175, pp. 3-11, March 2019.