Image Details
Caption: Fig. 4.
Mean nightly J (blue), H (green), and Ks (red) backgrounds vs. time for the two 2MASS observatories. Backgrounds at the J and H bands primarily arise from airglow. The Ks background depends on both airglow and thermal background and thus is seasonal.
© 2006. The American Astronomical Society. All rights reserved. Printed in U.S.A.