6 papers
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…
NSF-DOE Vera C. Rubin Observatory Observations of Interstellar Comet 3I/ATLAS (C/2025 N1)
Colin Orion Chandler, Pedro H. Bernardinelli, Mario JuriÄ +305
We report on the observation and measurement of astrometry, photometry, morphology, and activityof the interstellar object 3I/ATLAS, also designated C/2025 N1 (ATLAS) with the NSF-…
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…
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…
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…
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…