Gravitational waves (GWs) in general relativity are assumed to contain only tensorial polarization states, with generic metric theories of gravity also allowing for vector- and scalar-polarized GWs. Assuming an association between the gravitational-wave and electromagnetic transients GW190521 and ZTF19abanrhr, we find a preference for tensorial GWs with a log 10 Bayes factor of 21.6 (with respect to

The dominant radioactive energy source powering SN Ia light curves is expected to switch from the decay of 56 Co to 57 Co at very late epochs. We use archival Hubble Space Telescope images of SN1992A obtained more than 900 days after explosion to constrain its cobalt isotopic abundance ratio and compare it to the well-studied event SN2011fe. We confirm the 57 Co/ 56 Co ratio for SN2011fe of 0.026 ± 0

The Transiting Exoplanet Survey Satellite (TESS) is the first high-precision full-sky photometric survey in space. We extracted light curves from a magnitude limited set of stars and other stationary luminous objects from the TESS Full Frame Images using the MIT Quick Look Pipeline. Here, we describe the techniques used to create light curves.

In the Milky Way, older stars tend to have higher vertical velocity dispersions and comprise a thicker component of the stellar disk. Historically, this has been attributed to the gradual vertical heating of stellar orbits. A competing explanation suggests that stars may have formed in thicker disks at earlier times, inheriting the turbulent velocities of the gas in which they formed. As the gas velocity

We present the first Data Release (DR1) from the Hubble Space Telescope (HST) Ultraviolet Legacy Library of Young Stars as Essential Standards (ULLYSES) program, a Director’s Discretionary program devoting approximately 1000 HST orbits to the production of an ultraviolet spectroscopic library of young high- and low-mass stars in the local universe. The science products in this release are combined

We present light curves from a magnitude limited set of stars and other stationary luminous objects from the TESS Full Frame Images, as reduced by the MIT Quick Look Pipeline (QLP). Our light curves cover the full two-year TESS Primary Mission and include ∼14,770,000 and ∼9,600,000 individual light curve segments in the Southern and Northern ecliptic hemispheres, respectively. We describe the detrending

Little is known about the abundances of lanthanides in the Chemically Peculiar HgMn stars. Evidence is presented in this Note that they are not important absorbers in the classical HgMn stars μ Lep and β Scl. A fully consistent abundance analysis of lanthanides on a single temperature scale, using the same atomic data and including hyperfine structure for a larger number of HgMn stars is necessary

We report the delivery to the Mikulski Archive for Space Telescopes of target pixel and light curve files for up to 160,000 targets selected from full-frame images (FFI) for each TESS Northern hemisphere observing sector. The data include calibrated target pixels, simple aperture photometry flux time series, and presearch data conditioning corrected flux time series. These data provide TESS users with

The formation of Supermassive black holes (SMBHs) early in the universe challenges our understanding of black holes formation, since they appear to be well-established by several hundred millions of years after the big bang. Therefore, theories including direct-collapse black holes and times of super-Eddington accretion are utilized to explain the phenomenon. Quasars can be studied to help explain

Riemann solvers play a vital role in fluid dynamics simulations. Extreme cases, however, can generate artificially negative pressures and magnetic monopoles, destabilizing the solver. Here we couple the numerical scheme of Waagan that maintains positivity with the constrained transport method to solve the magnetohydrodynamics equations. This extends the applicability of the Waagan scheme to a wider

We present a fast velocity update for the drag-force solver described in Benítez-Llambay et al. for N species. This velocity update is valid when drag forces between N − 1 species are negligible, a regime of particular relevance to dust dynamics in gaseous protoplanetary disks. The complexity of the solution is ##IMG## [http://ej.iop.org/images/2515-5172/4/11/198/rnaasabc7beieqn1.gif] {${ \mathcal

Photometric B , V , R , and H α observations of the young open cluster M29 have been used to search for emission-line stars. Four stars with prominent H α emission are identified. One of these may be a Herbig AeBe star that shows significant variation in emission strength during the four-month observing interval.

We present the results of MASTER Global Robotic Net optical observations of the region within the LIGO/Virgo S200219ac error-box, triggered during the O3 run. We observed 1124 square degrees inside the 3 σ error box during a half month. We present the identified optical transients found during this study, which are not related to gravitational waves, and briefly discuss the MASTER observation strategy

The archival IUE spectra of the late B giant HR 6990 are used to show that the absorption lines undergo large radial velocity variations in 2 spectra taken 4 months and 10 days apart. These large RV variations confirm that HR 6990 is a spectroscopic binary. The detection of strong lines of P ii , Ga ii , Ga iii and Hg ii show that the brightest member of the system, HR 6990 A, is not a normal late

Wolf 1130 is a triple system containing an ultramassive white dwarf (Wolf 1130B), an M subdwarf (Wolf 1130A) and a T8 subdwarf (Wolf 1130C). We set out to determine a precise mass for Wolf 1130B by phase-folding TESS photometry to the previously reported orbital period. Each orbit was fit for ellipsoidal, Doppler beaming, and thermal photometric variability. We found that the measured beaming amplitude

On mission sol 783 (at Martian solar longitude ( L S ) of 217°), Mars Science Laboratory's MastCam instrument imaged a faint glow, extending upwards from the horizon (Figure 1(a)). The images were acquired from 18:58 to 19:01 LTST, nearly an hour after sunset occurred at 18:05 LTST, providing an opportunity to examine illumination in the Martian sky around sunset. The radiance of the observed glow

The Supernova X-Ray Database was established a few years ago to make X-ray data on supernovae (SNe) publicly available via an elegant searchable web interface. The database has recently been updated to PhP7, had security updates done, and moved to a new server, ensuring its long-term stability. We urge astronomers to continue to download the data as needed for their work. Those with X-ray data on SNe

Herschel/SPIRE observations of Uranus are used to search for stratospheric hydrogen chloride (HCl) emission at 41.74 cm −1 . HCl was not detected and instead 3 σ upper limits were determined; <6.2 ppb (<2.0 × 10 14 molecules cm −2 ) for a 0.1 mbar step profile and <0.40 ppb (<1.2 × 10 14 molecules cm −2 ) for a 1 mbar step profile. HCl is expected to have an external source and these upper limits are

Large satellite constellations in low-Earth orbit seek to be the infrastructure for global broadband Internet and other telecommunication needs. We briefly review the impacts of satellite constellations on astronomy and show that the Internet service offered by these satellites will primarily target populations where it is unaffordable, not needed, or both. The harm done by tens to hundreds of thousands

Strong gravitational lensing is an ideal tool for mapping the distribution of dark matter and for testing the values of cosmological parameters. Forthcoming surveys such as Euclid and the Rubin Observatory Large Synoptic Telescope Survey should increase the number of known strong lensing systems significantly, with for example over 100,000 such systems predicted in the Euclid wide survey. In this short

The DESI Milky Way Survey (MWS) will observe ≥8 million stars between16 < r < 19 mag, supplemented by observations of brighter targets under poor observing conditions. The survey will permit an accurate determination of stellar kinematics and population gradients, characterize diffuse substructure in the thick disk and stellar halo, enable the discovery of extremely metal-poor stars and other rare

The Dark Energy Spectroscopic Instrument (DESI) will execute a nearly magnitude-limited survey of low redshift galaxies(0.05 ≤ z ≤ 0.4, median z ≈ 0.2). Clustering analyses of this Bright Galaxy Survey (BGS) will yield the most precise measurements to date of baryon acoustic oscillations and redshift-space distortions at low redshift. DESI BGS will comprise two target classes: (i) BRIGHT ( r < 19.5

I present the future approach distances and times of the stars Gliese 710 and R Cra run toward the future under a global galactic model with input parameters from the Gaia repositories. I found that the star Gliese 710 will approach the Sun closer than previously estimated. These results can confirm other calculations done to find the remarkable differences between the results of models with pre-Gaia

X-ray missions with microcalorimeter technology will resolve spectral features with unprecedented detail. In this work, we improve the H-like K α energies for elements between6 ≤ Z ≤ 30 for the release version of the spectral simulation code Cloudy to match laboratory energies. We update the ionization potential ( I ion ) for these elements and add a fourth-order polynomial to the level energy difference

Using deep machine learning we show that the internal velocities of galaxies can be retrieved from optical images trained using 4596 systems observed with the SDSS-MaNGA survey. Using only i -band images we show that the velocity dispersions and the rotational velocities of galaxies can be measured to an accuracy of 29 km s −1 and 69 km s −1 respectively, close to the resolution limit of the spectroscopic

The Doppler beaming amplitude of a M dwarf is amplified relative to a blackbody of the same temperature because of deep TiO absorption features in M dwarf spectra. A strong Na feature at 5890 Å coincides with the short wavelength cutoff of the Transiting Exoplanet Survey Satellite response function, which also increases the beaming amplitude. As a result, the Doppler beaming effect for a 3000 K object

DESI will precisely constrain cosmic expansion and the growth of structure by collecting ∼35 million redshifts across ∼80% of cosmic history and one third of the sky to study Baryon Acoustic Oscillations (BAO) and Redshift Space Distortions (RSD). We present a preliminary target selection for an Emission Line Galaxy (ELG) sample, which will comprise about half of all DESI tracers. The selection consists

The DESI survey will observe more than 8 million candidate luminous red galaxies (LRGs) in the redshift range0.3 < z < 1.0. Here we present a preliminary version of the DESI LRG target section developed using Legacy Surveys Data Release 8 g , r , z and W 1 photometry. This selection yields a sample with a uniform surface density of ∼600 deg −2 and very low predicted stellar contamination and redshift

A model of the brightness of the “visorsat” Starlink spacecraft is presented based on published information on the engineering design and 80 observations of individual visorsats. Comments are offered on the implications of this model on the visibility of visorsat spacecraft across the sky.

Detectors that use HgCdTe exhibit Count Rate Non-Linearity (CRNL), where the integrated photon-generated charge in a pixel has an undesirable variation with photon arrival rate, at fixed delivered photon dose. Correcting for this is essential to meet the science goals of the Roman Space Telescope. The CRNL effect is distinct from signal-level-dependent (but photon-rate-independent) nonlinearity. We

The DESI survey will measure large-scale structure using quasars as direct tracers of dark matter in the redshift range0.9 < z < 2.1 and using quasar Ly α forests at z > 2.1. We present two methods to select candidate quasars for DESI based on imaging in three optical ( g , r , z ) and two infrared ( W 1, W 2) bands. The first method uses traditional color cuts and the second utilizes a machine-learning

We describe here a layered approach to the robust determination of the broad characteristics of the asteroseismic signal from red-giant stars. No single stringent test can exclude all false results. The use of multiple, weak tests not only provides robust results but also avoids over-constraining the parameter space.

This paper presents classification spectroscopy of 6 cataclysmic variables obtained with the Liverpool Telescope. These objects were discovered and identified as likely dwarf novae by the Gaia Alerts or ASAS-SN transient surveys.

We present preliminary results of a submillimeter spectral line survey of a strongly lensed dusty star-forming galaxy (DSFG) at z ∼ 2, near the peak epoch of cosmic star formation. We use data from the Submillimeter Array, which recently completed a systems upgrade that substantially increased the instantaneous bandwidth. Focusing on the brightest spectral lines of CO and atomic carbon, we characterize

We announce here the public availability of a catalog of ν ∼ 3 GHz Quick Look observations from the first epoch of the Very Large Array Sky Survey. The catalog consists of three distinct and linkable tables, namely (a) the detected radio components, (b) the host identifications with total source properties for single-component, and close double/triple radio sources (angular separations of <10″), and

We use a stacking method to study the radial light profiles of luminous red galaxies (LRGs) at redshift ∼0.62 and ∼0.25, out to a radial range of 200 kpc. We do not find noticeable evolution of the profiles at the two redshifts. The LRG profiles appear to be well approximated by a single Sérsic profile, although some excess light can be seen outside 60 kpc. We quantify the excess light by measuring

We present the results of deep narrowband imaging of two nested shells around the blue supergiant ALS 19653, which confirm that the outer shell is physically associated with the star.

AE Aqr objects are a class of cataclysmic variable stars in which the rapidly rotating magnetosphere of the white dwarf (WD) primary centrifugally expels most infalling gas before it can accrete onto the WD. The expulsion of the accretion flow via this “magnetic propeller” extracts angular momentum from the WD and produces large-amplitude, aperiodic flares in optical photometry. The eponymous AE Aqr

55 Cancri e is an ultra-short period transiting Super-Earth observed by TESS in Sector 21. Using this photometry, we measure the occultation depth in the TESS bandpass, leveraging the precise transit light curve and comparing multiple detrending methods. We measure the occultation depth to be (15.0 ± 4.8) ppm—a staggeringly small change in brightness, yet one detected by TESS in just a single sector

We use the 1D stellar evolution code MESA to run select models at one solar mass at near zero metallicity to examine the effect of a lack of catalysts for CNO burning on the evolution of these models. We find that for metallicities below 10 −10 ##IMG## [http://ej.iop.org/images/2515-5172/4/9/172/rnaasabbc0eieqn1.gif] {${Z}_{\odot }$} a loop occurs on the HR diagram as the star evolves off the main

We analyze time-series spectroscopy of the white dwarf merger candidate J005311 and confirm the unique nature of its optical spectrum. We detect an additional broad emission feature peaking at 343 nm that was predicted in the Gvaramadze et al. (2019) models. Comparing ten spectra taken with the Large Binocular Telescope, we find significant variability in the profile of the strong O vi 381.1/383.4 nm

We investigated the rest-frame ≈0.1–5 yr X-ray variability properties of an unbiased and uniformly selected sample of 24 broad absorption line (BAL) and 35 mini-BAL quasars, making it the largest representative sample used to investigate such variability. We find that the distributions of X-ray variability amplitudes of these quasar populations are statistically similar to that of non-BAL, radio-quiet

The tangent point method (TPM) is commonly used to calculate the rotation curve of the inner portion of the Milky Way, relying on the assumption that along one line of sight, the point tangent to the Galactic center is the point where the observed radial velocity is an extremum. This work compares rotation curves derived from the TPM, using neutral hydrogen gas data, and direct measurements of stellar

We searched the possible historical records for the young magnetar Swift J1818-5937, and found a guest star in AD 1798 that might be associated with it.

Stellar clusters formed within Giant Molecular Clouds are mass segregated. This is either because massive stars are born at the center of the clusters, or because they migrate to the center due to gravitational interactions. We analyze a run from the STARFORGE simulation suite to identify what role the above processes play in determining mass segregation. We find that clusters begin as inversely- or

The interaction of a SN ejecta with a pre-existing circumstellar material (CSM) is one of the most promising energy sources for a variety of optical transients. Recently, a semi-analytic method developed by Chatzopoulos et al. (2012, hereafter CWV12) has been commonly used to describe the optical light curve behaviors under such a scenario. We find that the expressions for many key results in CWV12

Silicate dust particles are part of many astronomical objects such as comets and circumstellar discs. In the spectrum, silicates exhibit a number of characteristic emission features. In this paper, we studied the contribution of quartz (SiO 2 ) particles to these features. Using the Mie theory, calculations were made of the intensity of light scattered by such particles. Two spectral features were

In this work we describe 59 galaxies discovered in the talk-forum of the Milky Way Project (MWP) by volunteers of the project. The MWP is based on infrared images by the Spitzer Space Telescope and primarily probes the Zone of Avoidance for star-forming regions located in the Milky Way. The list of galaxies found here include 35 galaxies previously not described, a possible galaxy cluster and two galaxies

Inspection of archival IUE spectra of the bright rapidly oscillating Ap star α Cir A reveal large flux variations from 1600 to 2000 Å over the 4.4790 day rotational period. At 1965 Å, where the flux reaches a maximum, the flux more than doubles between phases of maximum and minimum flux. These large flux variations are most likely caused by the passage of spots or belts of overabundant elements in

High-cadence Transiting Exoplanet Survey Satellite (TESS) observations are promising for studies of short-term pulsational variability in magnetic O stars, which usually have long rotation periods of the order of months or years. The Of?p star NGC 1624-2 is of special interest as it possesses the strongest magnetic field measured among O stars, together with a giant magnetosphere. We detect three significant

SNe Ia are likely the thermonuclear explosions of carbon–oxygen white-dwarf stars, but their progenitor systems remain elusive. A few theoretical scenarios for the progenitor systems have been suggested, which have been shown to agree with some observational properties of SNe Ia. However, several computational challenges prohibit a robust comparison to the observations. We focus on the observed ##IMG##

The EXPRES Stellar-Signals Project is providing sets of high-fidelity, spectroscopic and photometric observations to enable direct comparisons of various approaches for disentangling stellar signals and true radial velocities (RVs). We will provide all EXPRES RVs, meta data, and activity indicators as well as high-precision photometric data from the Fairborn Automatic Photoelectric Telescopes (APTs)

We present new ALMA 233 GHz continuum observations of the FU Orionis Object HBC722. With these data we detect HBC722 at millimeter wavelengths for the first time, use this detection to calculate a circumstellar disk mass of0.024 M ⊙ , and discuss implications for the burst triggering mechanism.

γ Draconis, a K5III star, showed radial velocity (RV) variations consistent with a 10.7 Jupiter mass planet from 2003 to 2011. After 2011, the periodic signal decayed, then reappeared with a phase shift. Hatzes et al. suggested that γ Dra’s RV variations could come from oscillatory convective modes, but did not fit a mathematical model. Here we assess whether a quasi-periodic Gaussian process—appropriate

The archival IUE spectra of the bright δ Scuti star ρ Puppis (HD 67523) reveal large flux variations from 2000 to 3000 Å over an 8 hr observing run. The time separating two successive flux maxima at 2900 Å is 3 hr and 19 minutes which compares well to the period of the radial fundamental mode. At 2900 Å, the flux at maximum is about 1.20 larger than at minimum which is consistent with a 260 K increase

This note reports flat galactic rotation curves coinciding with observation and originating in Laplace’s classical field equation. Dark matter, identified with a primordial fluid populating the entire universe, is represented by the homogeneous Klein–Gordon equation (KGE). The key element is the novel solution for the KGE discovered by the leading author in 1994, expressed as a permanent background

FRB 121102 was the first Fast Radio Burst (FRB) that was shown to repeat. Since its discovery in 2012, more than two hundred bursts have been detected from the source. These bursts exhibit a diverse range of spectral and temporal characteristics and many questions about their origin and form remain unanswered. Here, we present a sample of radio bursts from FRB 121102 detected using the Lovell telescope

I demonstrate that a very simple and safe change to the planning software filter assignment algorithm for the Ultraviolet/Optical Telescope (UVOT) onboard the Neil Gehrels Swift Observatory can reduce the number of filter wheel rotations by >10%, and its adoption is thus likely to significantly extend the usable lifetime of the UVOT instrument.

We present new photometric and spectroscopic data on the low-mass, eclipsing binary star NSVS 11868841. Light and velocity data are analyzed and modeled. Resulting best-fit models indicate a change in the orbital period. Our 2019 October observation of secondary eclipse occurs 0.01042 days prior to that predicted by the latest published ephemeris when assuming a circular orbit. Our spectroscopic data

An improved algorithm for dome following for an altitude-azimuth telescope mount is presented, with a specific implementation in ASCOM.