Recent observational surveys of the outer solar system provide evidence that Neptune's distant
The apparent clustering in longitude of perihelion
- NSF-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
More Like this
-
more » « less
Abstract n :1 mean motion resonances may harbor relatively large reservoirs of trans-Neptunian objects (TNOs). In particular, the discovery of two securely classified 9:1 resonators, 2015 KE172and 2007 TC434, by the Outer Solar System Origins Survey is consistent with a population of order 104such objects in the 9:1 resonance with absolute magnitudeH r < 8.66. This work investigates whether the long-term stability of such populations in Neptune’sn :1 resonances can be used to constrain the existence of distant 5–10M ⊕planets orbiting at hundreds of au. The existence of such a planet has been proposed to explain a reported clustering in the orbits of highly eccentric “extreme” trans-Neptunian objects (or eTNOs), although this hypothesis remains controversial. We engage in a focused computational case study of the 9:1 resonance, generating synthetic populations and integrating them for 1 Gyr in the presence of 81 different test planets with various masses, perihelion distances, eccentricities, and inclinations. While none of the tested planets are incompatible with the existence of 9:1 resonators, our integrations shed light on the character of the interaction between such planets and nearbyn :1 resonances, and we use this knowledge to construct a simple heuristic method for determining whether or not a given planet could destabilize a given resonant population. We apply this method to the currently estimated properties of Planet 9, and find that a large primordial population in the 15:1 resonance (or beyond), if discovered in the future, could potentially constrain the existence of this planet. -
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.more » « less
-
more » « less
Abstract The most distant known trans-Neptunian objects (TNOs), those with perihelion distance above 38 au and semimajor axis above 150 au, are of interest for their potential to reveal past, external, or present but unseen perturbers. Realizing this potential requires understanding how the known planets influence their orbital dynamics. We use a recently developed Poincaré mapping approach for orbital phase space studies of the circular planar restricted three-body problem, which we have extended to the case of the 3D restricted problem with
N planetary perturbers. With this approach, we explore the dynamical landscape of the 23 most distant TNOs under the perturbations of the known giant planets. We find that, counter to common expectations, almost none of these TNOs are far removed from Neptune’s resonances. Nearly half (11) of these TNOs have orbits consistent with stable libration in Neptune’s resonances; in particular, the orbits of TNOs 148209 and 474640 overlap with Neptune’s 20:1 and 36:1 resonances, respectively. Five objects can be ruled currently nonresonant, despite their large orbital uncertainties, because our mapping approach determines the resonance boundaries in angular phase space in addition to semimajor axis. Only three objects are in orbital regions not appreciably affected by resonances: Sedna, 2012 VP113 and 2015 KG163. Our analysis also demonstrates that Neptune’s resonances impart a modest (few percent) nonuniformity in the longitude of perihelion distribution of the currently observable distant TNOs. While not large enough to explain the observed clustering, this small dynamical sculpting of the perihelion longitudes could become relevant for future, larger TNO data sets. -
more » « less
Abstract Manx comets are objects on long-period comet orbits that are inactive as they approach perihelion. They are of particular interest because they may help constrain solar system formation models. 2013 LU28 was discovered as an inactive asteroidal object on 2013 June 8 at a heliocentric distance of 21.8 au. Images and photometric data were obtained of 2013 LU28 from multiple telescopes from pre-discovery data in 2010 until the present. Its spectral reflectivity is consistent with typical organic-rich comet surfaces with colors of
σ upper limits on the nucleus size of 79.9 km from the NEOWISE survey assuming the same albedo, since the NEOWISE survey is not very sensitive to objects this small at this distance. The heliocentric light curve suggests possible activity betweenr ∼ 17 and 13 au where 2013 LU28 is brighter than expected. This is consistent with outgassing from CO or CO2. Using surface brightness profiles, we estimate an upper limit of ∼0.01 kg s−1for micron-sized dust that can be produced without us detecting it for the inactive portion of the light curve, and upper limits of ∼1 kg s−1for CO and ∼1.5 kg s−1for CO2between 20 and 14.7 au. -
more » « less
Abstract We have discovered evidence of cometary activity originating from (551023) 2012 UQ192(alternately designated 2019 SN40), which we dynamically classify as a Jupiter Family Comet (JFC). JFCs have eccentric Jupiter-crossing orbits and originate in the Kuiper Belt. Analysis of these objects can provide vital information about minor planets in the outer solar system, such as the distribution of volatiles within the solar system. Activity on 2012 UQ192was first recognized by volunteers on our NASA Partner Citizen Science project
Active Asteroids . Through our own examination of archival image data, we found a total of ∼30 images presenting strong evidence of activity near perihelion during two separate orbits. 2012 UQ192is notable as we found it to be recurrently active. When 2012 UQ192approaches its perihelion passage in 2027 September, we predict it will reactivate and will be a prime subject for follow-up observations.
