# Temperatures of lunar impact flashes: mass and size distribution of small impactors hitting the Moon

## TL;DR

This study analyzes lunar impact flashes to determine impact temperatures, energies, and size distributions of small meteoroids hitting the Moon, providing insights into near-Earth object populations.

## Contribution

It introduces a method to derive impact energies from flash temperatures and links impact events to meteoroid streams, refining mass and size estimates.

## Key findings

- Impact temperatures range from 1,300 to 5,800 K.
- Impactor masses range from a few grams to hundreds of grams.
- Impactor sizes are a few centimeters, following a known size distribution.

## Abstract

Lunar impact flashes have been monitored over the last 20 years for determining the mass frequency distribution of near-Earth objects in the cm-dm size range. In this work, using telescopic observations in R and I band from the NELIOTA database, impact flash temperatures are derived. They are found to range between approximately 1,300 and 5,800 K. In addition, it is also found that temperature values appear to have a distribution significantly broader than a Gaussian function, therefore making it difficult to estimate the impact flash luminous energy by assigning an average temperature. By measuring the flash temperatures and assuming a black body emission, here we derive the energy of the impacts. We also study the potential link of each event to individual meteoroid streams, which allows us to assign an impact velocity and therefore constrain the projectile mass. Impactor masses are found to range between a few to hundreds of grams, while their sizes are just of few centimetres following a size frequency distribution similar to other studies.