We present observations of a powerful solar eruption, accompanied by an X8.2 solar flare, from NOAA Active Region 12673 on 2017 September 10 by the Solar Ultraviolet Imager (SUVI) on the GOES-16 spacecraft. SUVI is noteworthy for its relatively large field of view, which allows it to image solar phenomena to heights approaching 2 solar radii. These observations include the detection of an apparent current sheet associated with magnetic reconnection in the wake of the eruption and evidence of an extreme-ultraviolet wave at some of the largest heights ever reported. We discuss the acceleration of the nascent coronal mass ejection to approximately 2000 km/s at about 1.5 solar radii. We compare these observations with models of eruptions and eruption-related phenomena. We also describe the SUVI data and discuss how the scientific community can access SUVI observations of the event.

Spitzer Space Telescope imaging from the Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) reveals a previously unidentified low-latitude rich star cluster near l ¼ 31N3, b ¼ À0N1. Near-infrared JHK 0 photometry from the Wyoming Infrared Observatory indicates an extinction of A V ' 15 AE 3 mag for cluster members. Analysis of 13 CO features along the same sight line suggests a probable kinematic distance of 3.1-5.2 kpc. The new cluster has an angular diameter of $1-2 pc, a total magnitude corrected for extinction of m K 0 ¼ 2:1, and a luminosity of M K ' À10:3 at 3.1 kpc. In contrast to young massive Galactic clusters with ages less than 100 Myr, the new cluster has no significant radio emission. Comparison with theoretical K-band luminosity functions indicates an age of at least several gigayears and a mass of at least 10 5 M . Unlike known old open clusters, this new cluster lies in the inner Galaxy at R GC ' 6:1 kpc. We designate this object ''GLIMPSE-C01'' and present evidence that it is a Milky Way globular cluster passing through the Galactic disk. We also identify a region of star formation and fan-shaped outflows from young stellar objects in the same field as the cluster. The cluster's passage through the Galactic molecular layer may have triggered this star formation activity.

We present Atmospheric Imaging Assembly observations of a structure we interpret as a current sheet associated with an X4.9 flare and coronal mass ejection that occurred on 2014February25 in NOAA Active Region 11990. We characterize the properties of the current sheet, finding that the sheet remains on the order of a few thousand kilometers thick for much of the duration of the event and that its temperature generally ranged between 8 and 10 MK. We also note the presence of other phenomena believed to be associated with magnetic reconnection in current sheets, including supra-arcade downflows and shrinking loops. We estimate that the rate of reconnection during the event was M A ≈0.004-0.007, a value consistent with model predictions. We conclude with a discussion of the implications of this event for reconnection-based eruption models.

The four Solar Ultraviolet Imagers (SUVI) on board the Geostationary Operational Environmental Satellite (GOES)‐16 and GOES‐17 and the upcoming GOES‐T and GOES‐U weather satellites serve as National Oceanic and Atmospheric Administration's operational solar coronal imagers. These four identically designed solar Extreme UltraViolet instruments are similar in design and capability to the Solar Dynamics Observatory‐Atmospheric Imaging Assembly suite of solar telescopes, and are planned to operationally span two solar cycles or more, from 2017 through 2040. We present the concept of operations for the SUVI instruments, operational requirements, and constraints. The reader is also introduced to the instrument design, testing, and performance characteristics. Finally, the various data products are described along with their potential utility to the operational user or researcher.

We present ultraviolet, optical, near-infrared, Spitzer mid-infrared, and radio images of 14 radio-selected objects in M 33. These objects are thought to represent the youngest phase of star cluster formation. We have detected the majority of cluster candidates in M 33 at all wavelengths. From the near-IR images, we derived ages 2-10 Myr, K S -band extinctions (A K S ) of 0-1 mag, and stellar masses of 10 3 -10 4 M ⊙ . We have generated spectral energy distributions (SEDs) of each cluster from 0.1 µm to 160 µm. From these SEDs, we have modeled the dust emission around these star clusters to determine the dust masses (1-10 3 M ⊙ ) and temperatures (40-90 K) of the clusters' local interstellar medium. Extinctions derived from the JHK S , Hα, and UV images are similar to within a factor of 2 or 3. These results suggest that eleven of the fourteen radio-selected objects are optically-visible young star clusters with a surrounding H ii region, that two are background objects, possibly AGN, and that one is a Wolf-Rayet star with a surrounding H ii region.

The GOES-R series is the latest in a long line of American geostationary weather satellites operated by NOAA (National Oceanic and Atmospheric Administration). The Solar Ultraviolet Imager (SUVI) is an instrument onboard Geostationary Operational Environmental Satellites, GOES-R series, part of NOAA's (National Oceanic and Atmospheric Administration) space weather monitoring fleet. GOES-16 SUVI is in operation and the GOES-17 SUVI has completed initial calibrations.SUVI is a generalized Cassegrain telescope with a large field of view that employs multilayer coatings optimized to operate in six extreme ultraviolet (EUV) narrow bandpasses centered at 9.4, 13.1, 17.1, 19.5, 28.4 and 30.4 nm. The SUVI EUV line set provides the best comprehensive feature and dynamics information for revealing and correlating both the low coronal signatures of coronal mass ejections (CME) triggers (for example, flares) and the high coronal signatures of the actual CME. SUVI acquires full disk images in EUV band pass every few minutes and telemeters the data to the ground for digital processing. These data will enable NOAA to monitor solar activity and to issue accurate near real-time alerts when space weather may possibly affect the performance and reliability of space-borne and ground-based technological systems and human endeavors. This paper describes key design drivers in the development of SUVI, methods used in the autonomous on-orbit calibration of the instrument, and the automated monitoring of the health and safety of the instrument during operations.

In order to utilize solar imagery for real-time feature identification and large-scale data science investigations of solar structures, we need maps of the Sun where phenomena, or themes, are labeled. Since solar imagers produce observations every few minutes, it is not feasible to label all images by hand. Here, we compare three machine learning algorithms performing solar image classification using extreme ultraviolet and Hα images: a maximum likelihood model assuming a single normal probability distribution for each theme from Rigler et al. (2012), a maximum-likelihood model with an underlying Gaussian mixtures distribution, and a random forest model. We create a small database of expert-labeled maps to train and test these algorithms. Due to the ambiguity between the labels created by different experts, a collaborative labeling is used to include all inputs. We find the random forest algorithm performs the best amongst the three algorithms. The advantages of this algorithm are best highlighted in: comparison of outputs to hand-drawn maps; response to short-term variability; and tracking long-term changes on the Sun. Our work indicates that the next generation of solar image classification algorithms would benefit significantly from using spatial structure recognition, compared to only using spectral, pixel-by-pixel brightness distributions.

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