ETNOs Movement and Gradient of Spectra (IMAGE) Instituto de Astrofísica de Canarias (IAC) Caption Sequence of images taken with the Gran Telescopio CANARIAS (GTC) to identify one of the ETNO´s studied in this article, 2013 RF98, where one can see how it moves during four consecutive nights. Below, right, visible spectra obtained with the GTC of the two objects 2004 VN112 and 2013 RF98. The red lines show the gradients of the spectra. Credit Julia de León (IAC). Usage Restrictions Documents and materials on the IAC website are copyright of the Instituto de Astrofísica de Canarias. Use for commercial and publicity purposes is not authorised. Text and images may only be reproduced with the prior express permission of the Science Communication and Education Unit of the Instituto de Astrofísica de Canarias. To request permission: Include the address of the image (or information about it) in a request addressed to the Head of the Communication and Scientific Culture Unit (secUC3@iac.es) explaining what the image will be used for. License Licensed content 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.