Satellite Showing Earth's Vegetation (image) University of California - Riverside Share Print E-Mail Caption Satellites monitor how 'greenness' changes with Earth's seasons. UCR scientists are studying the accompanying changes in atmospheric composition as a marker for life on distant planets. Credit NASA Usage Restrictions None Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.