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We present visible and mid-infrared imagery and photometry of temporary Jovian co-orbital comet P/2019 LD$_2$ taken with HST/WFC3, Spitzer/IRAC, the GROWTH telescope network, visible spectroscopy from Keck/LRIS and archival ZTF observations taken between 2019 April and 2020 August. Our observations indicate that the nucleus of LD$_2$ has a radius between 0.2-1.8 km assuming a 0.08 albedo and a coma dominated by $sim$100$mu$ m-scale dust ejected at $sim$1 m/s speeds with a $sim$1 jet pointing in the SW direction. LD$_2$ experienced a total dust mass loss of $sim$10$^8$ kg at a loss rate of $sim$6 kg/s with Af$rho$/cross-section varying between $sim$85 cm/125 km$^2$ and $sim$200 cm/310 km$^2$ from 2019 April 9 to 2019 Nov 8. If the increase in Af$rho$/cross-section remained constant, it implies LD$_2$s activity began $sim$2018 November when within 4.8 au of the Sun, implying the onset of H$_2$O sublimation. We measure CO/CO$_2$ gas production of $lesssim$10$^{27}$ mol/s /$lesssim$10$^{26}$ mol/s from our 4.5 $mu$m Spitzer observations, $g$-$r$ = 0.59$pm$0.03, $r$-$i$ = 0.18$pm$0.05, $i$-$z$ = 0.01$pm$0.07 from GROWTH observations, H$_2$O gas production of $lesssim$80 kg/s scaling from our estimated $C_2$ production of $Q_{C_2}lesssim$7.5$times10^{24}$ mol/s from Keck/LRIS spectroscopy. We determine that the long-term orbit of LD$_2$ is similar to Jupiter family comets having close encounters with Jupiter within $sim$0.5 Hill radius in the last $sim$3 y, within 0.8 Hill radius in $sim$9 y. Additionally, 78.8$%$ of our orbital clones are ejected from the Solar System within $1 times 10^{6}$ years having a dynamical half-life of 3.4 $times 10^5$ years.
Gateway Centaur and Jupiter co-orbital P/2019 LD2 (ATLAS) (Sarid et al. 2019) provides the first opportunity to observe the migration of a Solar System small body from a Centaur orbit to a Jupiter Family Comet (JFC) four decades from now (Kareta et a
The recently discovered object P/2019 LD2 (ATLAS) was initially thought to be a Jupiter Trojan asteroid, until dynamical studies and the appearance of persistent cometary activity revealed that this object is actually an active Centaur. However, the
Comet P/2019 LD2 has orbital elements currently resembling those of a Jupiter Trojan, and therefore superficially appears to represent a unique opportunity to study the volatile content and active behavior of a member of this population for the first
We observed Episodically Active Asteroid (6478) Gault in 2020 with multiple telescopes in Asia and North America and have found that it is no longer active after its recent outbursts at the end of 2018 and start of 2019. The inactivity during this ap
We present visible and near-infrared photometric and spectroscopic observations of interstellar object 2I/Borisov taken from 2019 September 10 to 2019 November 29 using the GROWTH, the APO ARC 3.5 m and the NASA/IRTF 3.0 m combined with post and pre-