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.

The Parker Solar Probe (PSP) spacecraft is measuring plasma properties of the solar wind to heliocentric distances as small as 0.125 au or 26.9 solar radii. One of the most important plasma parameters is the strength of the magnetic field. A variety of radioastronomical remote sensing measurements also provide information on the magnetic field, from the solar surface to heliocentric distances of about

The latest eruption of the recurrent nova LMC 1968 was extensively observed by Swift with its X-ray Telescope instrument. A comparison with the Swift data set from the 2016 eruption shows that the X-ray evolution was remarkably similar just as the evolution of the optical photometry and spectroscopy was similar during previously observed eruptions. The only difference is a surprising decrease in the

Elemental abundances are derived for 17 Com B for 16 elements. They reinforce the Am status of this star. We show that the measured abundances are properly reproduced by stellar models including atomic diffusion and a parametrized turbulent diffusion coefficient. This parameterization agrees with that used in previous studies of Am stars.

We obtained high-resolution, diffraction limited imaging of the candidate binary RR Lyrae UV Oct using Gemini-South/Zorro. We detect no companions between 0.″1 and 1.″2, with a contrast of Δ m ∼ 5 mag, placing a mass constraint for any possible main sequence companion of m < 0.67 M ⊙ .

The low mass end of the Initial Mass Function (IMF) is a component of star formation that is not well understood. By analyzing Hubble Space Telescope (HST) images of star-forming regions, we aimed to provide data to constrain the shape of the low-mass IMF. We performed point-spread function (PSF) fitting using the Astropy Photutils package v0.6 on shallow HST Wide Field Camera 3 images taken in filters

When Pre-Main Sequence stars have two spectral types, an earlier one measured in the optical and a later one in the IR, the hotter one implies a greater Hertzsprung–Russell Diagram (HRD) mass than the cooler one. The mass discrepancy may be removed by plotting the stars on a modified HRD showing log (Luminosity) versus log (surface gravity). Placing two Pre-Main Sequence stars in Taurus, BP Tau and

Our research focuses on determining the dynamical orbital parameters associated with galaxy collisions. We are accomplishing this by optimizing numerical models of galactic interactions with astronomical observations of colliding galaxies and measuring the uncertainty in the parameter space of these models. This paper will focus on how we compare our numerical models to observed colliding galaxies