Shadow Test (image) University of Arizona Share Print E-Mail Caption Visualization of the new gauge developed to test the predictions of modified gravity theories against the measurement of the size of the M87 shadow. Credit D. Psaltis, UArizona; EHT Collaboration Usage Restrictions This visual may only be used in conjunction with reporting on or posting of this news release. Credit must be given as indicated. 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.