Free Access

Fig. 2


Observational geometry of Saturn from Herschel, and estimations of the contribution of Saturn’s rings to the disc-averaged spectrum. Panel a) shows the size of the planet in arcseconds and the small ring-opening angle as Saturn’s northern hemisphere passed the spring equinox. The SPIRE FWHM at 50 cm-1 is shown as the dotted line close to Saturn’s limb. The size of the SPIRE beam width is compared to the width of Saturn and the A, B and C rings in panel b). The fractional area of the SPIRE beam occupied by each of the rings is given in panel c), and was used to calculate the contribution of ring emission and absorption to the spectrum as a fraction of the total signal in d). Contributions smaller than 2% are within the estimated uncertainties on the SPIRE data.

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.