Shown below are the Sun's far-side images of acoustic travel-time shifts
(red/orange background with dark patches highlighting active regions) and near-side magnetic field (grey background with green/yellow
areas highlighting strong magnetic field). The synchronic image shows the most recent far-side result, and the two-hemisphere video
shows results of the last 30 days. The far-side acoustic images are obtained every 12 hours using 31-hour continuous near-side
Doppler-velocity observations. For more details of the far-side imaging data, please refer to this document.
For a view of 11 years of the Sun's near- and far-side active regions, click synchronic view and spherical view . For a daily comparison of far-side images using time-distance technique and holography technique, please click here.
Click here for a movie of synchronic maps for the past 30 days.
HMI time-distance helioseismic data-analysis pipeline generates the Sun's near-full-disk flow field, covering 120°×120° area with a depth from 0 - 20 Mm.
These results are available every 8 hours, typically two weeks behind real time.
Shown below on the right is the most recent map of supergranulation, represented by the divergence of the horizontal flow field. Shown below on the left is a large-scale synoptic flow map for the most recent Carrington rotation with magnetic field background.
The systematic center-to-limb effect is removed from these data to our best knowledge.
One also needs to be cautioned that results in and near active regions may be affected by the magnetic field. Synoptic flows can be directly downloaded from this webpage, and near-full-disk maps should be donwloaded from JSOC page (these data are still being uploaded to JSOC. Please check back soon). Users are suggested to refer to this document for more details.
For each Carrington rotation, the near-full-disk subsurface flow maps can be averaged for the Sun's differential rotation and meridional flow at various depths of 0 - 20 Mm. Shown below are the temporal evolution of the torsional oscillation and residual meridional flow after long-term mean profiles of rotation and meridional flow are subtracted from the respective profiles for each Carrington rotation, covering the period from May 2010 to the most recent Carrington rotation. In the torsional oscillation plot, positive (negative) speed is faster (slower) than the mean flow. In the residual meridional flow plot, positive (negative) speed is pole-ward (equator-ward). Data for all available depths, in FITS format, are available for downloading through this webpage (click "DATA ACCESS" above), and users are suggested to refer to this document for more details.
The Sun's interior meridional circulation can be inverted from time-distance travel-time-shift measurements, after the systematic center-to-limb effect and surface magnetic effect are removed. Shown left is a hemisphere-symmetrized meridional circulation profile, obtained through disentangling the center-to-limb effect and the flow-induced signals from all across-the-disk measurements. Please refer to this paper for details.