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We present proper-motion measurements and long-slit spectroscopy of the Mg  ii nebula around η Carinae obtained with the Wide Field Camera 3 and Space Telescope Imaging Spectrograph (STIS) aboard the Hubble Space Telescope. Detailed kinematics of the Mg  ii -emitting material constrain the geometry and history of mass-loss from η Car, and provide estimated ejection dates, assuming linear, ballistic motions. These measurements show that the neutral gas immediately outside the Homunculus – i.e. material into which the Homunculus is now expanding – was expelled over several decades prior to the Great Eruption, thus representing unshocked pre-eruption stellar wind. Material outside the Homunculus is therefore not part of a Hubble-like flow from the Great Eruption itself. This result discriminates between versions of merger-in-a-triple models for η Car. The STIS spectrum of Mg  ii -emitting gas along the projected outflow axis displays radial velocities consistent with bipolar expansion, redshifted several hundred km s−1 towards the northwest, similarly blueshifted towards the southeast, and with low internal velocity dispersion. The η Car system was therefore losing mass in a relatively fast, low-density polar wind for several decades that probably traces the critical inspiral phase preceding a merger event. [ABSTRACT FROM AUTHOR]

We present proper motion measurements of the oxygen-rich ejecta of the LMC supernova remnant N132D using two epochs of Hubble Space Telescope Advanced Camera for Surveys data spanning 16 years. The proper motions of 120 individual knots of oxygen-rich gas were measured and used to calculate a center of expansion (CoE) of α = 5h25m01.ˢ71 and δ = −69°38′41.″64 (J2000) with a 1 σ uncertainty of 2.″90. This new CoE measurement is 9.″2 and 10.″8 from two previous CoE estimates based on the geometry of the optically emitting ejecta. We also derive an explosion age of 2770 ± 500 yr, which is consistent with recent age estimates of ≈2500 yr made from 3D ejecta reconstructions. We verified our estimates of the CoE and age using a new automated procedure that detected and tracked the proper motions of 137 knots, with 73 knots that overlap with the visually identified knots. We find that the proper motions of the ejecta are still ballistic, despite the remnant's age, and are consistent with the notion that the ejecta are expanding into an interstellar medium cavity. Evidence for explosion asymmetry from the parent supernova is also observed. Using the visually measured proper motion measurements and corresponding CoE and age, we compare N132D to other supernova remnants with proper motion ejecta studies. [ABSTRACT FROM AUTHOR]

We present a detailed analysis of the protostellar outflow activity in the massive star-forming region NGC 3324, as revealed by new Early Release Observations (EROs) from the James Webb Space Telescope (JWST). Emission from numerous outflows is revealed in narrow-band images of hydrogen Paschen α (Paα) and molecular hydrogen. In particular, we report the discovery of 24 previously unknown outflows based on their H2 emission. We find three candidate driving sources for these H2 flows in published catalogues of young stellar objects (YSOs), and we identify 15 infrared point sources in the new JWST images as potential driving protostars. We also identify several Herbig–Haro (HH) objects in Paα images from JWST ; most are confirmed as jets based on their proper motions measured in a comparison with previous Hubble Space Telescope (HST) Hα images. This confirmed all previous HST -identified HH jets and candidate jets, and revealed seven new HH objects. The unprecedented capabilities of JWST allow the direct comparison of atomic and molecular outflow components at comparable angular resolution. Future observations will allow quantitative analysis of the excitation, mass-loss rates, and velocities of these new flows. As a relatively modest region of massive star formation (larger than Orion but smaller than starburst clusters), NGC 3324 offers a preview of what star formation studies with JWST may provide. [ABSTRACT FROM AUTHOR]

We present new proper-motion measurements of optically emitting oxygen-rich knots of supernova remnant 1E 0102.2-7219 (E0102), which are used to estimate the remnant's center of expansion and age. Four epochs of high-resolution Hubble Space Telescope images spanning 19 yr were retrieved and analyzed. We found a robust center of expansion of α = 1h04m02.ˢ48 and δ = −72°01′53.″92 (J2000) with 1σ uncertainty of 1.″77 using 45 knots from images obtained with the Advanced Camera for Surveys using the F475W filter in 2003 and 2013 having the highest signal-to-noise ratio. We also estimate an upper limit explosion age of 1738 ± 175 yr by selecting the knots with the highest proper motions and these knots are assumed to be the least decelerated. We find evidence of an asymmetry in the proper motions of the knots as a function of position angle. We conclude that these asymmetries were most likely caused by interaction between E0102's original supernova blast wave and an inhomogeneous surrounding environment, as opposed to intrinsic explosion asymmetry. The observed nonhomologous expansion suggests that the use of a free expansion model inaccurately offsets the center of expansion and leads to an overestimated explosion age. We discuss our findings as they compare to previous age and center of expansion estimates of E0102, as well as their relevance to a recently identified candidate central compact object. [ABSTRACT FROM AUTHOR]

We present the first images of the nebula around η Carinae obtained with the Wide Field Camera 3 (WFC3) onboard the Hubble Space Telescope (HST), including an ultraviolet (UV) image in the F280N filter that traces Mg  ii  emission, plus contemporaneous imaging in the F336W, F658N, and F126N filters that trace near-UV continuum, [N  ii ], and [Fe  ii ], respectively. The F336W and F658N images are consistent with previous images in these filters, and F126N shows that for the most part, [Fe  ii ] λ12567 traces clumpy shocked gas seen in [N  ii ]. The F280N image, however, reveals Mg  ii  emission from structures that have not been seen in any previous line or continuum images of η Carinae. This image shows diffuse Mg  ii  emission immediately outside the bipolar Homunculus nebula in all directions, but with the strongest emission concentrated over the poles. The diffuse structure with prominent radial streaks, plus an anticorrelation with ionized tracers of clumpy shocked gas, leads us to suggest that this is primarily Mg  ii  resonant scattering from unshocked, neutral atomic gas. We discuss the implied structure and geometry of the Mg  ii  emission, and its relation to the Homunculus lobes and various other complex nebular structures. An order of magnitude estimate of the neutral gas mass traced by Mg  ii  is 0.02 M⊙, with a corresponding kinetic energy around 1047 erg. This may provide important constraints on polar mass-loss in the early phases of the great eruption. We argue that the Mg  ii  line may be an excellent tracer of significant reservoirs of freely expanding, unshocked, and otherwise invisible neutral atomic gas in a variety of stellar outflows. [ABSTRACT FROM AUTHOR]

We present a comprehensive study of phase curves and secondary eclipses in the Kepler data set using all data from 16 quarters that were available in 2013-2014. Our sample consists of 20 confirmed planets with Rp > 4 Re, P < 10 d, Vmag < 15. Here we derive their temperatures and albedos, with an eye toward constraining models for the formation and evolution of such planets. Where there was overlap our results confirm parameters derived by previous studies, whereas we present new results for Kepler 1b-8b, 12b-15b, 17b, 40b, 41b, 43b, 44b, 76b, 77b, and 412b derived in a consistent manner. We also present light-curve analyses for Kepler 91b and Kepler 74b, which both show extra dimmings at times other than from the expected primary and secondary eclipses. Corrected for thermal emission, we find most of the massive planets from our sample to be low in albedo (<0.1) with a few having higher albedo (>0.1). [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM PUBLISHER]