Search Publications
Long-term Evolution in Ionization of Ejecta Illuminated by Eta Carinae
Corcoran, Michael F.; Moffat, Anthony F. J.; Damineli, Augusto +6 more
Changes in the flux and spectrum of Eta Carinae (η Car) since 1900 have been attributed to the evolution of the central binary by some. Others suggest evolution in the occulting ejecta. The brightness jump in the 1940s, which coincided with the appearance of narrow forbidden emission lines, may have been caused by the clearing and ionization of in…
High-Energy Spectra of Black Hole and Neutron Star Low-Mass X-Ray Binaries
Pszota, Gábor
In the case of low-mass X-ray binaries, the companion star is often too faint for detection; therefore, there is no chance for dynamical studies to independently determine the mass of the compact object. In the absence of a mass estimate, one cannot make a distinction as to whether the binary hosts a black hole or neutron star. Therefore, the ques…
On the Influence of the Solar Wind on the Propagation of Earth-impacting Coronal Mass Ejections
Gopalswamy, Nat; Srivastava, Nandita; Kumar, Sandeep +1 more
Coronal mass ejections (CMEs) are subject to changes in their direction of propagation, tilt, and other properties as they interact with the variable solar wind. We investigated the heliospheric propagation of 15 Earth-impacting CMEs observed during 2010 April to 2018 August in the field of view (FOV) of the Heliospheric Imager (HI) on board the S…
A Tale of Three Dwarfs: Cluster-based Star Formation Histories of Blue Compact Dwarf Galaxies
Calzetti, Daniela; Whitmore, Bradley C.; Chandar, Rupali +9 more
We present a new study of the cluster populations in the blue compact dwarf galaxies (BCD) ESO185-IG13, ESO338-IG04, and Haro11, based on new and archival high-resolution images taken by the Hubble Space Telescope, and the first to probe the populations older than ≈100 Myr. BCDs are believed to experience intense bursts of star formation (includin…
X-ray occultations in active galactic nuclei: Physical properties of eclipsing clouds as part of the broad-line region cloud ensemble
Risaliti, G.; Pietrini, P.; Torricelli-Ciamponi, G.
Context. Short-term X-ray variability in active galactic nuclei (AGNs) can be explained as being due to varying X-ray absorption induced by the temporary occultation of the primary X-ray source, when moving absorbing clouds cross the line of sight to the X-ray source itself. Earlier work suggests that these absorbing clouds have physical propertie…
The near-infrared degree of polarization in debris disks. Toward a self-consistent approach to model scattered light observations
Bayo, A.; Henning, Th.; Milli, J. +2 more
Context. Debris disks provide a unique opportunity to probe the properties of small µm-sized particles, allowing us to peer into the constituents of their parent bodies, namely the young analogs of comets and the asteroids of our Solar System.
Aims: In the past, studies of the total intensity phase function - that is, the brightness of …
Observations of Uranus at High Phase Angle as Seen by New Horizons
Mayorga, L. C.; Singer, Kelsi N.; Stern, S. Alan +14 more
We present flux measurements of Uranus observed at phase angles of 43.°9, 44.°0, and 52.°4 by the Multispectral Visible Imaging Camera on the New Horizons spacecraft during 2023, 2010, and 2019, respectively. New Horizons imaged Uranus at a distance of about 24–70 au (2023) in four color filters, with bandpasses of 400–550 nm, 540–700 nm, 780–975 …
Short-term solar eruptive activity prediction models based on machine learning approaches: A review
Xu, Long; Zhao, Zhongrui; Erdélyi, R. +3 more
Solar eruptive activities, mainly including solar flares, coronal mass ejections (CME), and solar proton events (SPE), have an important impact on space weather and our technosphere. The short-term solar eruptive activity prediction is an active field of research in the space weather prediction. Numerical, statistical, and machine learning methods…
Prospecting in-situ resources for future crewed missions to Mars
Postberg, Frank; Poulet, François; Bishop, Janice L. +3 more
The installation of planetary and lunar human outposts might be an important step for future solar system exploration by both public space agencies and private companies. Humans living and working in these artificially created habitats will possibly depend, among other life support approaches, on bio-regenerative life support systems to produce an…
Statistical geoeffectiveness of solar-interplanetary disturbance events of type II radio bursts and CMEs/shocks
Yan, Jingye; Yu, Quanyingqi
Understanding and predicting the geoeffectiveness of solar activity on Earth is crucial for space weather. Therefore, predicting the impact of coronal mass ejections (CMEs) and their associated interplanetary (IP) shocks on Earth is essential. Observations of CMEs near the Sun can be used for these prediction and to study their propagation and evo…