arXiv subjects

Tessa Frincke

Publications and source records attributed to Tessa Frincke.

3 recordsLinked to original sources

arXiv2025

The Feasibility of a Spacecraft Flyby with the Third Interstellar Object 3I/ATLAS from Earth or Mars

We investigate the feasibility of a spacecraft mission to conduct a flyby of 3I/ATLAS, the third macroscopic interstellar object discovered on July 1 2025, as it traverses the Solar System. There are both ready-to-launch spacecraft currently in storage on Earth, such as Janus, and spacecraft nearing the end of their missions at Mars. We calculate minimum $ΔV$ single-impulse direct transfer trajectories to 3I/ATLAS both from Earth and from Mars. We consider launch dates spanning January 2025 through March 2026 to explore obtainable and hypothetical mission scenarios. Post-discovery Earth departures require a challenging $ΔV\gtrsim24$ km s$^{-1}$ to fly by 3I/ATLAS. By contrast, Mars departures from July 2025 - September 2025 require $ΔV\sim5$ km s$^{-1}$ to achieve an early October flyby -- which is more feasible with existing propulsion capabilities. \added{We further calculate the phase angle and flyby velocity for these trajectories, noting that the resulting flyby speeds would impose significant observational and engineering challenges that a mission would need to overcome.} We discuss how existing spacecraft could be used to observe 3I/ATLAS and how spacecraft at other locations in the Solar System could be repurposed to visit future interstellar objects on short notice.

astro-ph.EP↗

arXiv2025

Prospects of a New $L_5$ Trojan Flyby Target for the Lucy Mission

NASA's Lucy spacecraft is en route to conduct the first close encounter with Jupiter's Trojans. While most scheduled flybys lie in the $L_4$ cloud, the only $L_5$ target is the Patroclus-Menoetius binary. Since each flyby offers unique insights into target and population properties unattainable from Earth, we examine the feasibility of including an additional, yet unknown, $L_5$ target while minimizing the impact on Lucy's primary mission. We use the background $L_5$ Trojans brighter than the completeness limit to model their absolute magnitude, spatial, and orbital distributions. A semi-analytical approach estimates the number of Trojans accessible to Lucy for a given $Δv$ budget in both pre- and post-Patroclus scenarios. Our results indicate that, while it is unlikely that any suitable Trojan lies on Lucy's nominal path, a moderate $Δv$ investment ($35-50\,\mathrm{m/s}$) could enable a sub-kilometer ($500-700\,\mathrm{m}$) flyby prior to the Patroclus encounter. Post-Patroclus, the likelihood of a similar flyby is $\sim60\%$ for $Δv\sim$ 50 m/s. Simulations with synthetic Trojans reveal that potential targets cluster near the node opposite to the encounter window, producing an optimal search period in late 2026 for both scenarios. Surveying the densest $10\%$ of this region would require under 5 nights with Subaru/HSC or under 2 nights with Rubin, using shift-and-stack techniques. A successful sub-kilometric flyby would expand Lucy's Trojan target size range and provide new constraints on collisional evolution and the long-standing asymmetry in the $L_4/L_5$ clouds. This nodal-clustering strategy could guide target searches in future Lucy extensions or other planetary flyby missions.

astro-ph.EP↗

arXiv2025

Discovery and Preliminary Characterization of a Third Interstellar Object: 3I/ATLAS

We report initial observations aimed at the characterization of a third interstellar object. This object, 3I/ATLAS or C/2025 N1 (ATLAS), was discovered on 2025 July 1 UT and has an orbital eccentricity of $e\sim6.1$, perihelion of $q\sim 1.36$ au, inclination of $\sim175^\circ$, and hyperbolic velocity of $V_\infty\sim 58$ km s$^{-1}$. We report deep stacked images obtained using the Canada-France-Hawaii Telescope and the Very Large Telescope that resolve a compact coma. Using images obtained from several smaller ground-based telescopes, we find minimal light curve variation for the object over a $\sim4$ day time span. The visible/near-infrared spectral slope of the object is 17.1$\pm$0.2 %/100 nm, comparable to other interstellar objects and primitive solar system small bodies (comets and D-type asteroids). 3I/ATLAS will be observable through early September 2025, then unobservable by Earth-based observatories near perihelion due to low solar elongation. It will be observable again from the ground in late November 2025. Although this limitation unfortunately prohibits detailed Earth-based observations at perihelion when the activity of 3I/ATLAS is likely to peak, spacecraft at Mars could be used to make valuable observations at this time.

astro-ph.EP↗