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Abstract The detached trans-Neptunian objects (TNOs) are those with semimajor axes beyond the 2:1 resonance with Neptune that are neither resonant nor scattering. Using the detached sample from the Outer Solar System Origins Survey (OSSOS) telescopic survey, we produce the first studies of their orbital distribution based on matching the orbits and numbers of the known TNOs after accounting for survey biases. We show that the detached TNO perihelion ( q ) distribution cannot be uniform but is instead better matched by two uniform components with a break near q ≈ 40 au. We produce parametric two-component models that are not rejectable by the OSSOS data set and estimate that there are 36,000 − 9000 + 12 , 000 detached TNOs with absolute magnitudes H r < 8.66 ( D ≳ 100 km) and semimajor axes 48 au < a < 250 au (95% confidence limits). Although we believe that these heuristic two-parameter models yield a correct population estimate, we then use the same methods to show that the perihelion distribution of a detached disk created by a simulated rogue planet matches the q distribution even better, suggesting that the temporary presence of other planets in the early solar system is a promising model to create today’s large semimajor axis TNO population. This cosmogonic simulation results in a detached TNO population estimate of 48,000 − 12 , 000 + 15 , 000 . Because this illustrates how difficult-to-detect q > 50 au objects are likely present, we conclude that there are (5 ± 2) × 10 4 dynamically detached TNOs, roughly twice as many as in the entire trans-Neptunian hot main belt.
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No Evidence for Orbital Clustering in the Extreme Trans-Neptunian Objects
Abstract The apparent clustering in longitude of perihelionϖand ascending node Ω of extreme trans-Neptunian objects (ETNOs) has been attributed to the gravitational effects of an unseen 5–10 Earth-mass planet in the outer solar system. To investigate how selection bias may contribute to this clustering, we consider 14 ETNOs discovered by the Dark Energy Survey, the Outer Solar System Origins Survey, and the survey of Sheppard and Trujillo. Using each survey's published pointing history, depth, and TNO tracking selections, we calculate the joint probability that these objects are consistent with an underlying parent population with uniform distributions inϖand Ω. We find that the mean scaled longitude of perihelion and orbital poles of the detected ETNOs are consistent with a uniform population at a level between 17% and 94% and thus conclude that this sample provides no evidence for angular clustering.
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- PAR ID:
- 10362302
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- DOI PREFIX: 10.3847
- Date Published:
- Journal Name:
- The Planetary Science Journal
- Volume:
- 2
- Issue:
- 2
- ISSN:
- 2632-3338
- Format(s):
- Medium: X Size: Article No. 59
- Size(s):
- Article No. 59
- Sponsoring Org:
- National Science Foundation
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