Observing Statistics
Observing Statistics
Here we give monthly summaries of time usages and losses, with a
focus on the period after the Wide Field Upgrade was completed. In
the run-up to full science operations, all aspects of science
operations became more efficient and productive. In order to
produce the most representative statistics, this reporting focuses
on the period after 1 April 2017, although some earlier statistics
are also included.
Monthly average time use statistics
based on night reports
(fractions of time spent on
science/engineering/weather/alignment/problems)
Sky quality averages
(seeing, transparency, etc)
Target acquisition statistics
(setup times, etc)
Summary of multi-year guider photometry data
used to generate the multipliers Object
Observability calculator:
data collected from
2019-01-01 through 2023-11-26
Image Quality:
using 1-minute averages of all data >0.5"
(N=557,901 measurements)
threshold
|
percentile
|
<3.00"
|
98.4%
|
<2.50"
|
94.8%
|
<2.25"
|
90.3%
|
<2.00"
|
81.8%
|
<1.75"
|
66.2%
|
<1.50"
|
40.5%
|
<1.25"
|
11.1%
|
<1.00"
|
0.4%
|
Transparency:
using 1-minute averages of all data >0% and
<110% (N=541,136 measurements)
threshold
|
percentile
observed*
|
percentile
|
P (>90%)
|
26.1%
|
17.7%
|
S (>50%)
|
90.3%
|
61.4%
|
N (>20%)
|
97.6%
|
66.4%
|
*overall we have 43% time lost to bad weather; we estimate that
~25% of that
lost time was spent still collecting guider images. Thus,
percentiles observed are
multiplied by 0.68 to get the percentile multipliers for each
threshold.
(without this correction, the multiplier on N time would be 98%,
which
would be highly unrealistic for planning purposes)
Last updated: Fri, 10 May 2024 20:30:45 +0000 sir
|
