This past quarter saw remarkable progress in starlight suppression technology, demonstrated across several fronts. At JPL, in the original High Contrast Imaging Testbed (HCIT-1), Gene Serabyn obtained narrow-band contrasts less than 1 x 10-9 with the vector vortex coronagraph. In the new HCIT-2, and also in narrow-band light, Olivier Guyon and collaborators reached 6 x 10-10 with the Phase Induced Amplitude Apodization (PIAA) coronagraph. Moreover, Mark Clampin at NASA/GSFC reached 3 x 10-9 contrast monochromatically with the Visible Nulling Coronagraph. These each represent about an order of magnitude improvement in performance over where they were a year ago. If these teams formally meet their Milestones in the New Year, as undoubtedly they will, they will each move on to the greater challenge of testing at broader bandwidths.
The new ExEP Technology Plan Appendix has been updated for 2012-13, and is in the final process of being edited for release. It maintains substantially the same direction as last year, but reflects the progress noted above and elsewhere. Perhaps the most interesting new direction the community has taken this past year has been to develop ideas for coronagraphy with partially obscured apertures – to potentially equip one NASA’s newly acquired 2.4-m telescopes for high-contrast imaging. Although this effort isn’t yet an integral part of the ExEP technology plan, there are up to date references included in the revised draft for the benefit of interested readers. Interesting times indeed.