HST previews are not currently working. We are investigating and apologize for the inconvenience.
For image previews we suggest that you try the Aladin option, and for spectral previews the SpecView option. Links to these options are found near the bottom of the preview page.
For ACS, STIS and NICMOS grism data you may find the HLA another good option.
Guidelines for Contributing Data to MAST
MAST accepts contributions in two main categories and has
guidelines for submission for each category:
High-Level Science Products