To RHESSI collaborators:

As many of you have already discovered, there have been difficulties accessing RHESSI resources for the past month. The cause is that our primary RHESSI server at Goddard, called "hesperia", was taken offline, and although we assumed that the downtime would be short, a month later we still have no estimate for when hesperia can be brought back online. Accordingly, we are transitioning to hosting everything at the Solar Data Analysis Center (SDAC), which had already been planned to be the final archive. Here are the latest statuses:

RHESSI Browser For the RHESSI Browser (http://sprg.ssl.berkeley.edu/~tohban/browser/), nearly all of the plot types are available again thanks to Kim Tolbert. This includes restored access to the RHESSI Image Archive. A couple of the plot types may be incomplete even when data are available, which is due to ongoing re-processing of the mission-long data set.

RHESSI data The RHESSI data is hosted on multiple mirrors, of which hesperia was only one. If your SSW (specifically, the `hessi` package) was updated more recently than February 2022, the unavailability of hesperia should have had minimal impact on accessing RHESSI data because the relevant code automatically tries one of the other mirrors. However, if you are unable to update your SSW, the automatic fallback may not work. Instead, you can expressly specify which mirror to try first. For example, to specify that the mirror at SSL (UC Berkeley) should be used, the IDL call is: ``` hsi_server, /ssl ```

Fermi/GBM solar data products In addition to RHESSI data, hesperia also hosted key parts of the solar-flare data pipeline for Fermi/GBM data, specifically the per-flare instrument-response files. As of yesterday, SSW (specifically, the `spex` package) has been updated by Kim with the up-to-date list of Fermi/GBM solar flares and the new location for the response files. Please update your SSW to be able to retrieve and analyze Fermi/GBM solar data using OSPEX.

Documentation I am unable to provide an estimate for when the RHESSI website will be available again. Fortunately, at least the documentation that is part of the SSW tree continues to be readily available online, e.g.:

* RHESSI Data Analysis Software: https://soho.nascom.nasa.gov/solarsoft/hessi/doc/aaa_main_hessi_doc.html * OSPEX documentation: https://soho.nascom.nasa.gov/solarsoft/packages/spex/doc/ospex_explanation.h...

Our apologies for not having a more prompt response to the surprise unavailability of hesperia, and please pardon some continued hiccups as we complete this transition to SDAC hosting. Happy holidays!

Albert Y. Shih RHESSI Deputy Mission Scientist