Tohoku-Hiroshima-Nagoya planetary spectra library: A method for characterizing planets in the visible to near infrared

TL;DR

This paper presents a comprehensive spectral library of all solar system planets, enabling comparison and characterization of planets in visible to near-infrared wavelengths, aiding in the study of both solar system and extrasolar planets.

Contribution

It introduces the first simultaneous visible to near-infrared spectral library for all solar system planets, facilitating planetary comparison and analysis.

Findings

Spectral patterns distinguish gas, soil, and ice planets.

The library enables comparison across all solar system planets.

Methods can be applied to analyze extrasolar planet spectra.

Abstract

There has not been a comprehensive framework for comparing spectral data from different planets.Such a framework is needed for the study of extrasolar planets and objects within the solar system. We have undertaken observations to compile a library of planet spectra for all planets, some moons, and some dwarf planets in the solar system to study their general spectroscopic and photometric natures. During May and November of 2008, we acquired spectra for the planets using TRISPEC, which is capable of simultaneous three-band spectroscopy in a wide wavelength range of 0.45 - 2.5 microns with low resolving power (lambda-over-Delta-lambda is 140 - 360). Patterns emerge from comparing the spectra. Analyzing their general spectroscopic and photometric natures, we show that it is possible to distinguish between gas planets, soil planets and ice planets. These methods can be applied to extrasolar observations using low resolution spectrography or broad-band filters. The present planet spectral library is the first library to contain observational spectra for all of the solar system planets, based on simultaneous observations in visible and near infrared wavelengths. This library will be a useful reference for analyzing extrasolar planet spectra, and for calibrating planetary data sets.