Over the past few weeks most HEASARC and associated pages (e.g., SkyView, Swift, Fermi, ...) have transitioned to serve data only through the secure HTTPS protocol, not the HTTP protocol that we have normally used in the past (though HTTPS has been available optionally for many years). This is in accordance with a directive of the federal Office of Management and Budget. When you try to access a page at the old HTTP link you will be automatically redirected to the same page using HTTPS. So for most users this transition should be seamless, since they will automatically transition to the new address.

However some software does not support HTTPS, notably the HEASARC's CFITSIO package. FTP access is still supported, so to access the HEASARC data from FTOOLS or CALDB we recommend using FTP URL's rather than the HTTP. E.g., use ftp://heasarc.gsfc.nasa.gov/rosat rather than http://heasarc.gsfc.nasasa.gov/FTP/rosat.

A workaround where the HEASARC's web servers redirect CFITSIO HTTP requests to FTP is supported by recently released versions of CFITSIO (3.42) and FTOOLS (6.21). These should allow transparent access to HEASARC data. Users having difficulty accessing HEASARC data are encouraged to update to these. Versions which fully support HTTPS are under development.

Java programs, although they can read HTTPS URL's, will not normally follow the redirects from HTTP to HTTPS. If you are accessing HEASARC data through Java programs, please use the HTTPS URLs. Also, the certificates used at the HEASARC require relatively recent versions of Java. If you are having difficulty accessing HEASARC data with Java programs, please upgrade. We recommend at least Java 1.8 v121.

Outside of Java there may be other software that does not follow redirections and will need to have any hardwired URLs updated to HTTPS.

Some users report problems accessing HEASARC using WGET. This seems to also be related to the certificates being used. You may wish to try adding the --no-check-certificate flag to your WGET commands if you are seeing issues.

If you have questions or issues with the transition, please get in touch with the HEASARC help desk.



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Last modified: Thursday, 13-Apr-2017 15:09:42 EDT