activity
20242026
collaborators

6 papers

astro-ph.EP2026

Measuring Apsidal Clustering

Amir Siraj, Christopher F. Chyba, Scott Tremaine

The decade-long debate over the existence of apsidal clustering in the outer solar system is poised for reignition given the plethora of distant trans-Neptunian object (TNO) discov…

astro-ph.EP2025

Revealing Callisto's Near Subsurface Thermophysical Properties with ALMA Calibration Data

Cole Meyer, Maria Camarca, Katherine de Kleer +3

Thermal images at different wavelengths probe varying subsurface depths of planetary bodies, and therefore can inform us about their compositions, thermophysical properties, and im…

astro-ph.EP2025

The Inner Kernel of the Classical Kuiper Belt

Amir Siraj, Christopher F. Chyba, Scott Tremaine

The `kernel' of the classical Kuiper belt was discovered by Petit et al. (2011) as a visual overdensity of objects with low ecliptic inclinations and eccentricities at semimajor ax…

astro-ph.EP2025

Limits on Stellar Flybys in the Solar Birth Cluster

Amir Siraj, Christopher F. Chyba, Scott Tremaine

The orbits of small bodies in the outer solar system are particularly sensitive to gravitational perturbations, including stellar flybys. Stellar clusters, with low velocity disper…

astro-ph.EP2025

Measuring the Mean Plane of the Distant Kuiper Belt

Amir Siraj, Christopher F. Chyba, Scott Tremaine

In the absence of any unseen planetary-mass bodies in the outer solar system, the mean plane of the distant Kuiper belt should be the same as the plane orthogonal to the angular mo…

astro-ph.EP2024

Orbit of a Possible Planet X

Amir Siraj, Christopher F. Chyba, Scott Tremaine

The plausibility of an unseen planet in the outer solar system, and the expected orbit and mass of such a planet, have long been a topic of inquiry and debate. We calculate the lon…