Planets residing within the hot-Neptune Desert are rare and studying their atmospheres can provide valuable insights into their formation and evolutionary processes. We present the atmospheric characterization of the first known ultra-hot Neptune, LTT-9779 b, using transmission spectroscopic observations obtained with the Hubble Space Telescope's

Our understanding of the γ-ray sky has improved dramatically in the past decade, however, the unresolved γ-ray background (UGRB) still has a potential wealth of information about the faintest γ-ray sources pervading the Universe. Statistical cross-correlations with tracers of cosmic structure can indirectly identify the populations that most

Standard local helioseismic diagnostics of large sunspots show the signature of anomalously strong compact scatterers of p-modes within about 1 Mm beneath their photospheres. We applied standard "subjacent-vantage phase-correlation helioseismic holography" to the major sunspot umbra and inner penumbra in NOAA AR12192 as it crossed central solar

In the past decade the study of exoplanet atmospheres at high-spectral resolution, via transmission/emission spectroscopy and cross-correlation techniques for atomic/molecular mapping, has become a powerful and consolidated methodology. The current limitation is the signal-to-noise ratio that one can obtain during a planetary transit, which is in

As the fields of stellar and exoplanetary study grow and revolutionary new detection instruments are created, it is imperative that a homogeneous, precise source of stellar parameters is available. This first work of the gr8stars collaboration presents the all-sky magnitude limited sample of 5645 bright F,G,K, and M type dwarfs, along with

The physics of recombination lines in the He I singlet system is expected to be relatively simple, supported by accurate atomic models. We examine the intensities of He I singlets λ3614, λ3965, λ5016, λ6678, and λ7281 and the triplet He I λ5876 in various types of ionized nebulae and compare them with theoretical predictions to test the validity of