<p>We present visible and mid-infrared imagery and photometry of temporary Jovian co-orbital comet P/2019 LD2 taken with Hubble Space Telescope/Wide Field Camera 3 (HST/WFC3), Spitzer Space Telescope/Infrared Array Camera (Spitzer/IRAC), and the GROWTH telescope network, visible spectroscopy from Keck/Low-Resolution Imaging Spectrometer (LRIS), and archival Zwicky Transient Facility observations taken between 2019 April and 2020 August. Our observations indicate that the nucleus of LD2 has a radius between 0.2 and 1.8 km assuming a 0.08 albedo and a coma dominated by &#8764;100 &#956;m-scale dust ejected at &#8764;1m s&#8722;1 speeds with a &#8764;1'' jet pointing in the southwest direction. LD2 experienced a total dust mass loss of &#8764;108 kg at a loss rate of &#8764;6 kg s<sup>&#8722;1</sup> with Af&#961;/ cross-section varying between &#8764;85 cm/125 km<sup>2</sup> and &#8764;200 cm/310 km<sup>2</sup> from 2019 April 9 to 2019 November 8. If the increase in Af&#961;/cross section remained constant, it implies LD2&#700;s activity began &#8764;2018 November when within 4.8 au of the Sun, implying the onset of H2O sublimation. We measure CO/CO<sub>2</sub> gas production of <10<sup>27</sup> mol s<sup>&#8722;1</sup>/<10<sup>26</sup> mol s<sup>&#8722;1</sup> from our 4.5 &#956;m Spitzer observations; g&#8211;r = 0.59 &#177; 0.03, r&#8211;i = 0.18 &#177; 0.05, and i&#8211; z = 0.01 &#177; 0.07 from GROWTH observations; and H2O gas production of <80 kg s<sup>&#8722;1</sup> scaling from our estimated C<sub>2</sub> production of Q<sub>C2</sub> < 7.5 x 10<sup>24</sup> mol s<sup>&#8722;1</sup> from Keck/LRIS spectroscopy. We determine that the long-term orbit of LD2 is similar to Jupiter-family comets having close encounters with Jupiter within &#8764;0.5 Hill radius in the last &#8764;3 y and within 0.8 Hill radius in &#8764;9 y. Additionally, 78.8% of our orbital clones are ejected from the solar system within 10<sup>6</sup> yr, having a dynamical half-life of 3.4 &#215; 10<sup>5</sup> yr.</p>