Remote-sensing Characterisation of Major Solar System Bodies with the Twinkle Space Telescope

TL;DR

This paper evaluates Twinkle space telescope's ability to perform spectroscopic remote sensing of Solar System bodies, demonstrating its potential to obtain high-quality spectra of planets, moons, and asteroids in various wavelength bands.

Contribution

It assesses Twinkle's observational capabilities and sensitivity limits for Solar System objects, highlighting its unique spectral coverage and rapid observation potential.

Findings

Twinkle can observe Solar System objects regularly.

High-resolution spectra with SNR > 100 are achievable in short exposures.

Capability varies across spectral bands, with effective observations of bright targets.

Abstract

Remote-sensing observations of Solar System objects with a space telescope offer a key method of understanding celestial bodies and contributing to planetary formation and evolution theories. The capabilities of Twinkle, a space telescope in a low Earth orbit with a 0.45m mirror, to acquire spectroscopic data of Solar System targets in the visible and infrared are assessed. Twinkle is a general observatory that provides on demand observations of a wide variety of targets within wavelength ranges that are currently not accessible using other space telescopes or that are accessible only to oversubscribed observatories in the short-term future. We determine the periods for which numerous Solar System objects could be observed and find that Solar System objects are regularly observable. The photon flux of major bodies is determined for comparison to the sensitivity and saturation limits of Twinkle's instrumentation and we find that the satellite's capability varies across the three spectral bands (0.4-1, 1.3-2.42, and 2.42-4.5{\mu}m). We find that for a number of targets, including the outer planets, their large moons, and bright asteroids, the model created predicts that with short exposure times, high-resolution spectra (R~250, {\lambda} < 2.42{\mu}m; R~60, {\lambda} > 2.42{\mu}m) could be obtained with signal-to-noise ratio (SNR) of >100 with exposure times of <300s.