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If you are in Michigan:
There are a lot of CORS stations within 250 KM of everywhere. OPUS-RS is likely to always succeed,
even if a few of the stations are offline, are missing data or are very noisy and must be discarded.
If you are in the middle of Utah there are very few CORS sites available on a good day:
On a bad day, if a few stations are offline or have not yet archived data then your OPUS-RS solution
will fail because there are not enough stations close to your occupation.
In many areas a single offline CORS station without data will make OPUS-RS impossible.
#4 Daily vs. Hourly CORS Availability
If you click a CORS station pin on the NGS CORS map, you will get a station summary which includes
an ‘Availability’ note. There are two availably types:
Daily Hourly
Daily means that a full day’s CORS station data is collected and then sometime after midnight UTC
the data is archived and becomes available for use as CORS data. Collection is ONCE PER DAY.
Hourly means that the previous hour’s data is collected and available immediately after the top of
each hour. Collection is EVERY HOUR.