From a Different Star: 3I/ATLAS in the context of the Ōtautahi-Oxford interstellar object population model

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Hopkins, Matthew J., Dorsey, Rosemary C., Forbes, John C., Bannister, Michele T., Lintott, Chris J., Leicester, Brayden
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866914016830423040
author Hopkins, Matthew J.
Dorsey, Rosemary C.
Forbes, John C.
Bannister, Michele T.
Lintott, Chris J.
Leicester, Brayden
author_facet Hopkins, Matthew J.
Dorsey, Rosemary C.
Forbes, John C.
Bannister, Michele T.
Lintott, Chris J.
Leicester, Brayden
contents The discovery of the third interstellar object (ISO), 3I/ATLAS (`3I'), provides a rare chance to directly observe a small body from another Solar System. Studying its chemistry and dynamics will add to our understanding of how the processes of planetesimal formation and evolution happen across the Milky Way's disk, and how such objects respond to the Milky Way's potential. In this Letter, we present a first assessment of 3I in the context of the Ōtautahi-Oxford model, which uses data from Gaia in conjunction with models of protoplanetary disk chemistry and Galactic dynamics to predict the properties of the ISO population. The model shows that both the velocity and radiant of 3I are within the expected range. Its velocity predicts an age of over 7.6 Gyr and a high water mass fraction, which may become observable shortly. We also conclude that it is very unlikely that 3I shares an origin with either of the previous two interstellar object detections.
format Preprint
id arxiv_https___arxiv_org_abs_2507_05318
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle From a Different Star: 3I/ATLAS in the context of the Ōtautahi-Oxford interstellar object population model
Hopkins, Matthew J.
Dorsey, Rosemary C.
Forbes, John C.
Bannister, Michele T.
Lintott, Chris J.
Leicester, Brayden
Earth and Planetary Astrophysics
Astrophysics of Galaxies
The discovery of the third interstellar object (ISO), 3I/ATLAS (`3I'), provides a rare chance to directly observe a small body from another Solar System. Studying its chemistry and dynamics will add to our understanding of how the processes of planetesimal formation and evolution happen across the Milky Way's disk, and how such objects respond to the Milky Way's potential. In this Letter, we present a first assessment of 3I in the context of the Ōtautahi-Oxford model, which uses data from Gaia in conjunction with models of protoplanetary disk chemistry and Galactic dynamics to predict the properties of the ISO population. The model shows that both the velocity and radiant of 3I are within the expected range. Its velocity predicts an age of over 7.6 Gyr and a high water mass fraction, which may become observable shortly. We also conclude that it is very unlikely that 3I shares an origin with either of the previous two interstellar object detections.
title From a Different Star: 3I/ATLAS in the context of the Ōtautahi-Oxford interstellar object population model
topic Earth and Planetary Astrophysics
Astrophysics of Galaxies
url https://arxiv.org/abs/2507.05318