Search Publications
BepiColombo Mio Observations of Low-Energy Ions During the First Mercury Flyby: Initial Results
Persson, Moa; Saito, Yoshifumi; Delcourt, Dominique +14 more
We present initial results of low-energy ion observations from BepiColombo's first Mercury flyby. Unprecedentedly high time resolution measurements of low energy ions at Mercury by BepiColombo Mio reveal rapid (a few seconds) and large (1-2 orders of magnitude) fluctuations of ion flux around the magnetopause and within the magnetosphere. Around t…
KK 242, A Faint Companion to the Isolated Scd Galaxy NGC 6503
Cannon, John M.; Anand, Gagandeep S.; Tully, R. Brent +4 more
Using Hubble Space Telescope imaging of the resolved stellar population of KK 242 = NGC 6503-d1 =PGC 4689184, we measure the distance to the galaxy to be 6.46 ± 0.32 Mpc and find that KK 242 is a satellite of the low-mass spiral galaxy NGC 6503 located on the edge of the Local Void. Observations with the Karl G. Jansky Very Large Array show signs …
The Effect of Molecular Cloud Properties on the Kinematics of Stars Formed in the Trifid Region
Gromadzki, Mariusz; Feigelson, Eric D.; Hillenbrand, Lynne A. +5 more
The dynamical states of molecular clouds may affect the properties of the stars they form. In the vicinity of the Trifid Nebula (d = 1180 ± 25 pc), the main star cluster (Trifid Main) lies within an expanding section of the molecular cloud; however, ~0.°3 to the north (Trifid North), the cloud's velocity structure is more tranquil. We acquired a C…
The OGLE Collection of Variable Stars. Over 2600 δ Scuti Stars in the Small Magellanic Cloud
Soszyński, I.; Udalski, A.; Szymański, M. K. +11 more
We present the first-ever collection of δ Scuti stars found over the entire area of the Small Magellanic Cloud (SMC). The sample consists of 2810 variables of which over 2600 objects belong to the SMC while the remaining stars are most likely members of the Milky Way's halo. The sample has been divided into 2733 single mode and 77 multimode pulsat…
Paleolake Inlet Valley Formation: Factors Controlling Which Craters Breached on Early Mars
Fassett, C. I.; Bamber, Emily R.; Goudge, T. A. +2 more
The ancient surface of Mars is dominated by degraded impact craters with reduced or eliminated rim relief. Some degraded craters have an inlet valley, while many remain fluvially isolated. Despite controlling Martian fluvial connectivity, few constraints exist on why some—but not all—degraded craters possess inlets. We compared a suite of properti…
Predicted trends in Milky Way bulge proper motion rotation curves: future prospects for HST and LSST
Gennaro, Mario; Clarkson, William I.; Sahu, Kailash C. +5 more
We use an N-body+smoothed particle hydrodynamics simulation of an isolated barred galaxy to study the age dependence of bulge longitudinal proper motion (µl) rotation curves. We show that close to the minor axis (|l| ~ 0○) the relatively young stars rotate more rapidly than the old stars, as found by Hubble Space Telesc…
Chandra Observations of Six Peter Pan Disks: Diversity of X-Ray-driven Internal Photoevaporation Rates Does Not Explain Their Rare Longevity
Kounkel, Marina; Kuchner, Marc J.; Wisniewski, John P. +6 more
We present Chandra X-ray observations of six previously identified Peter Pan objects, rare ∼40 Myr systems with evidence of primordial disk retention. We observe X-ray luminosities (0.8–3.0 keV) ranging from log L x ∼ 27.7–29.1. We find that our Peter Pan sample exhibits X-ray properties similar to that of weak-lined T Tauri stars and…
Absolute dimensions and apsidal motion of the eclipsing binaries V889 Aquilae and V402 Lacertae
Granzer, T.; Ribas, I.; Morales, J. C. +6 more
Context. Double-lined eclipsing binaries allow the direct determination of masses and radii, which are key for testing stellar models. With the launch of the TESS mission, many well-known eclipsing binaries have been observed at higher photometric precision, permitting the improvement of the absolute dimension determinations.
Aims: Using TESS…
Alternate oscillations of Martian hydrogen and oxygen upper atmospheres during a major dust storm
Tsuchiya, Fuminori; Yoshida, Nao; Terada, Naoki +11 more
Dust storms on Mars play a role in transporting water from its lower to upper atmosphere, seasonally enhancing hydrogen escape. However, it remains unclear how water is diurnally transported during a dust storm and how its elements, hydrogen and oxygen, are subsequently influenced in the upper atmosphere. Here, we use multi-spacecraft and space te…
LSST Survey Strategies and Brown Dwarf Parallaxes
Gizis, John E.; Yoachim, Peter; Jones, R. Lynne +2 more
The Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST) has the potential to measure parallaxes for thousands of nearby ultracool dwarfs, enabling improved measurements of the brown dwarf luminosity function. We develop a simple model to estimate the number of L dwarfs and T dwarfs with parallaxes with signal-to-noise ratio greater …