Timothy R. Holt
A5062646532- Astro and Planetary Science
- Planetary Science and Exploration
- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Space Exploration and Technology
- Astrophysics and Star Formation Studies
- Gamma-ray bursts and supernovae
- Scientific Computing and Data Management
- Astronomical and nuclear sciences
- Evolution and Paleontology Studies
- Spacecraft Design and Technology
- Space Satellite Systems and Control
- Nuclear physics research studies
- Paleontology and Evolutionary Biology
- Isotope Analysis in Ecology
- Space Science and Extraterrestrial Life
- Methane Hydrates and Related Phenomena
- High-pressure geophysics and materials
- Photocathodes and Microchannel Plates
- Advanced Scientific Research Methods
- Advanced biosensing and bioanalysis techniques
- Geology and Paleoclimatology Research
- Amphibian and Reptile Biology
- Nuclear Physics and Applications
- Ichthyology and Marine Biology
University of Southern Queensland
2018-2025
Southwest Research Institute
2020-2022
Swinburne University of Technology
2018
Abstract Over the past three decades, we have witnessed one of great revolutions in our understanding cosmos—the dawn Exoplanet Era. Where once knew just planetary system (the solar system), now know thousands, with new systems being announced on a weekly basis. Of thousands found to date, however, there is only that can study up-close and personal—the system. In this review, describe current for exoplanetary science community—with focus processes thought shaped see today. section one,...
Abstract We report the detection of 239 trans-Neptunian objects discovered through ongoing New Horizons survey for distant minor bodies being performed with Hyper Suprime-Cam mosaic imager on Subaru Telescope. These were in images acquired either r 2 or recently commissioned EB- gri filter using shift and stack routines. Due to extremely high stellar density search region downstream spacecraft, new machine learning techniques had be developed manage false-positive rate bogus candidates...
Abstract The planned NASA Habitable Worlds Observatory (HWO) flagship mission aims to image and spectroscopically characterise 25 Earth-size planets in the habitable zones of their stars. However, one giant planet zone can ruin your whole day. Recent work has examined current state our knowledge on presence or absence such objects samples likely HWO targets, that been found wanting; even Saturn-mass remain undetectable many these systems. In this work, we present simulations assessing degree...
The planned NASA Habitable Worlds Observatory (HWO) flagship mission aims to image and spectroscopically characterise 25 Earth-size planets in the habitable zones of their stars. However, one giant planet zone can ruin your whole day. Recent work has examined current state our knowledge on presence or absence such objects samples likely HWO targets, that been found wanting; even Saturn-mass remain undetectable many these systems. In this work, we present simulations assessing degree which...
Abstract We present time-resolved visible spectrophotometry of 2020 CD 3 , the second known minimoon. The was taken with Keck I/Low Resolution Imaging Spectrometer between wavelengths 434 and 912 nm in B g V R I RG850 filters as it leaving Earth–Moon system on March 23 UTC. spectrum resembles V-type asteroids some lunar rock samples a 434–761 reddish slope ∼18%/100 ( – r = 0.62 ± 0.08 i 0.21 0.06) an absorption band at ∼900 corresponding to z −0.54 0.10. Combining our measured H 31.9 0.1...
Abstract We present visible and mid-infrared imagery photometry of temporary Jovian co-orbital comet P/2019 LD 2 taken with Hubble Space Telescope/Wide Field Camera 3 (HST/WFC3), Spitzer Telescope/Infrared Array (Spitzer/IRAC), the GROWTH telescope network, spectroscopy from Keck/Low-Resolution Imaging Spectrometer (LRIS), archival Zwicky Transient Facility observations between 2019 April 2020 August. Our indicate that nucleus has a radius 0.2 1.8 km assuming 0.08 albedo coma dominated by...
The Jovian Trojans are two swarms of objects located around the L$_4$ and L$_5$ Lagrange points. population is thought to have been captured by Jupiter during Solar system's youth. Within swarms, six collisional families identified in previous work, with four swarm, L$_5$. Our aim investigate stability Trojan a particular focus on these families. We find that members escape at linear rate, primordial (23.35% escape) (24.89% sizes likely 1.31 1.35 times larger than today. Given rates were...
Abstract Jupiter and Saturn each have complex systems of satellites rings. These can be classified into dynamical groups, implying similar formation scenarios. Recently, a larger number additional irregular been discovered around both gas giants that yet to classified. The aim this paper is examine the relationships between rings giants, using an analytical technique called cladistics . Cladistics traditionally used living organisms, “tree life.” In work, we perform first cladistical study...
Vera C. Rubin Observatory will be a key facility for small body science in planetary astronomy over the next decade. It carry out Legacy Survey of Space and Time (LSST), observing sky repeatedly u, g, r, i, z, y course ten years using 6.5 m effective diameter telescope with 9.6 square degree field view, reaching approximately r = 24.5 mag (5-{\sigma} depth) per visit. The resulting dataset provide extraordinary opportunities both discovery characterization large numbers (10--100 times more...
Abstract We present observations of five stellar occultations for (11351) Leucus and reports from two efforts on (21900) Orus. Both objects are prime mission candidate targets the Lucy Discovery mission. Combined results indicate a very dark surface with p V = 0.037 ± 0.001, which is derived average multichord occultations. Our estimate triaxial ellipsoidal shape axial diameters 63.8 × 36.6 29.6 km assuming that spin pole normal to line sight. The actual object only roughly elliptical in...
Abstract We report the discovery of a highly eccentric long-period Jovian planet orbiting hot-Jupiter host HD 83443. By combining radial velocity data from four instruments (AAT/UCLES, Keck/HIRES, HARPS, Minerva-Australis) spanning more than two decades, we find evidence for with m sin <?CDATA $i={1.35}_{-0.06}^{+0.07}$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>i</mml:mi> <mml:mo>=</mml:mo> <mml:msubsup> <mml:mrow> <mml:mn>1.35</mml:mn> </mml:mrow>...
The Jovian Trojans are two swarms of small objects that share Jupiter's orbit, clustered around the leading and trailing Lagrange points, L$_4$ L$_5$. In this work, we investigate Trojan population using technique astrocladistics, an adaptation `tree life' approach used in biology. We combine colour data from WISE, SDSS, Gaia DR2 MOVIS surveys with knowledge physical orbital characteristics Trojans, to generate a classification tree composed clans distinctive characteristics. identify 48...
Asteroid pairs, two objects that are not gravitationally bound to one another, but share a common origin, have been discovered in the Main belt and Hungaria populations. Such pairs of major interest, as study their evolution under variety dynamical influences can indicate time since pair was created. To date, no asteroid found Jovian Trojans, despite presence several binaries collisional families population. The search for Trojan population is particular given importance Trojans tracers...
Vera C. Rubin Observatory will be a key facility for small body science in planetary astronomy over the next decade. It carry out Legacy Survey of Space and Time (LSST), observing sky repeatedly u, g, r, i, z, y course ten years using 6.5 m effective diameter telescope with 9.6 square degree field view, reaching approximately r = 24.5 mag (5-{\sigma} depth) per visit. The resulting dataset provide extraordinary opportunities both discovery characterization large numbers (10--100 times more...
We report the detection of 239 trans-Neptunian Objects discovered through on-going New Horizons survey for distant minor bodies being performed with Hyper Suprime-Cam mosaic imager on Subaru Telescope. These objects were in images acquired either r2 or recently commissioned EB-gri filter using shift and stack routines. Due to extremely high stellar density search region down stream spacecraft, new machine learning techniques had be developed manage false positive rate bogus candidates...
In this work, we examine seven systems discovered by TESS, to see whether there is any room in those for an additional planet (or several) lurk unseen between the two planets already confirmed therein. five of (namely HD 15337; 21749; 63433; 73583 and LTT 3780) find that ample undiscovered move have been discovered. other words, as they currently stand, are not tightly packed. stark contrast, perturbative influence known TOI-1670 such ruled out. The final system, TOI 421, more challenging....
Abstract In this work, we examine seven systems discovered by TESS, to see whether there is any room in those for an additional planet (or several) lurk unseen between the two planets already confirmed therein. five of (namely, HD 15337, 21749, 63433, 73583, and LTT 3780), find that ample undiscovered move have been discovered. other words, as they currently stand, are not tightly packed. stark contrast, perturbative influence known TOI-1670 such ruled out. The final system, TOI 421, more...
Ice giants are the only unexplored class of planet in our Solar System. Much that we currently know about these systems challenges understanding how planets, rings, satellites, and magnetospheres form evolve. We assert an ice giant Flagship mission with atmospheric probe should be a priority for decade 2023-2032.
We outline the challenges faced by planetary science community in era of next-generation large-scale astronomical surveys, and highlight needs that must be addressed order for to maximize quality quantity scientific output from archival, existing, future while satisfying NASA's NSF's goals.
The small satellites are a diverse group of objects offering insights into the early formation Solar System and its collisional history.They can be subdivided several groups: inner moons, outer irregular Martian moons asteroids, Centaurs/KBOs/TNOs.Many these objects, especially irregulars or their progenitors, thought to captured asteroids Kuiper Belt Objects: spacecraft mission that included them as targets would thus yield information on an object came from elsewhere in System.Objects...
Traditionally, heliophysics is characterized as the study of near-Earth space environment, where plasmas and neutral gases originating from Earth Sun, to a lesser extent other solar system bodies, interact in ways that are detectable only through in-situ or close-range (usually within ~10 AU) remote sensing.As result, has data environment around handful objects, particular Sun Earth.Comparatively, Astrophysics an extensive array but more limited temporal, spatial, wavelength information any...