STAND-IN DATA. This catalog contains 2,279 ZTF detections and 1,000,000 synthetic fixture rows — NOT Visnjan-Washington observations. Stand-in data is loaded while the VW Data Analysis Pipeline is built. Do not use these measurements for science.
Statistics
The survey's observing record, computed from survey.exposures. These
are ZTF's observing statistics, not Visnjan-Washington's — the stand-in notice above
applies to every plot here as much as it does to a search result, and the synthetic
fixture is excluded by default because its cadence is invented (a perfectly uniform
one exposure every 0.01 day), not observed.
How often the survey observed. A gap
is a week it didn't run, not one with nothing to see.
Hover a column for its date, its total and how that total divides
between bands.
Zoomed to
Jan 1, 2020
– Dec 31, 2020;
the from and to in the address take any date, not just
the whole years the chips offer.
Cumulative exposures
The same data, accumulated — flat stretches are when the survey was not running,
which the bar chart above makes easy to miss among the weeks that did have
data. Hover a point for the running total and what it added.
Exposures by filter
How the observing above divides between bands — always the whole split, whichever
band is currently picked. Click a slice to show only that band in
the charts above.
Revisits and light-curve length
How often the survey comes back to the same object, over the same bands and
dates as the charts above. Grouped by ZTF's own association of the stand-in
data (ztf_oid), which is the only thing linking one detection to
another until phase 2 builds objects — so these describe what the stand-in
catalog can support, not a VW data product.
Only the 2,279 detections ZTF associated this
way are counted, out of 1,002,279 sources in the
catalog: a source with no association has no object identity here at all, so
it is absent from these charts rather than appearing as a one-point curve.
Objects with a curve
17
from 321 linked detections
Typical curve length
5 points
median over those objects
Typical revisit
2 d
median gap between consecutive points
Longest baseline
354 d
first to last point on one object
Time between consecutive detections
The sampling, which is what sets the periods a light curve can recover: a
signal shorter than the typical gap is not resolved, and one near a spike in
this histogram aliases against it. Log-spaced buckets — revisits run from
minutes to years. Hover a row for its share.
Detections per object
How long the curves are. An object with a handful of points has a position and
little else — fitting a period or an orbit takes tens of points at least, so
it is the bottom rows here that are worth plotting.
Plot the
best-sampled one (86 points).
Same data as JSON: /api/statistics?fixture=show&from=2020-01-01&to=2020-12-31