Shadow-bands Research & Observation System (SAROS)

Shadow-Bands Research & Observation System (SAROS) is a new BalloonSat project developing payloads for investigating a phenomenon known as shadow-bands, which are oscillating streaks of visible light that occur before and after solar eclipse totality.

This project is scheduled to fly during two upcoming North American solar eclipses:

Annular Eclipse - October 14, 2023

Total Eclipse - April 8th, 2023


Jaiden Stark (

SAROS Mission Patch

Map of upcoming Solar Eclipses 

(Credit: NASA

Shadow-bands observed on the ground


Shadow bands are an oscillatory light phenomenon found during a solar eclipse. They appear as lines of shadows that move across the ground just prior to and following eclipse totality. They have been observed for centuries  and appear for approximately 120 seconds prior to and immediately after eclipse totality.

The accepted atmospheric scintillation hypothesis proposes that the Earth’s atmosphere produces this effect by refracting the highly focused light from the eclipse corona. Effectively, the focused light of the solar crescent is being smeared by the atmosphere. Patterns start out random and disorganized but become more organized as the crescent narrows towards totality. Band direction and speed would be determined by variables of the atmosphere, including wind speed and direction.

Since atmospheric variables (pressure, density, wind speed & direction) change with altitude, we expect in-situ shadow band measurements to vary throughout the atmosphere. To directly characterize shadow bands during a solar eclipse, we propose a high altitude balloon mission carrying instruments for measuring shadow band size and frequency, along with atmospheric conditions.


Shadow-bands during the 2017 North American Solar Eclipse


Rendering of balloon during solar eclipse


CONTACT:  Jaiden Stark (