VWDB Višnjan–Washington Sky Survey
Stand-in data
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.

Clump by day week month Dates all 2018 2019 2020 2021 2022 2023 2024 2025 Band zg zi zr Synthetic fixture excluded
Exposures
186
in 3 bands (zg, zi, zr)
Nights observed
82
2.3 exposures per night
Baseline
330 d
Jan 21, 2023 – Dec 17, 2023
Open-shutter time
1.6 h
summed exposure time
Median depth
21.01 mag
limiting magnitude per exposure
Median airmass
1.18
secant of the zenith angle

Exposures per month

How often the survey observed. A gap is a month 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, 2023 – Dec 31, 2023; the from and to in the address take any date, not just the whole years the chips offer.

Jan 1, 2023Mar 25, 2023Jun 17, 2023Sep 8, 2023Dec 1, 2023680Jan 2023 — 8 exposures (zg 5, zi 1, zr 2)Feb 2023 — 19 exposures (zg 7, zi 3, zr 9)Mar 2023 — 10 exposures (zg 4, zi 1, zr 5)Apr 2023 — 68 exposures (zg 38, zi 3, zr 27)May 2023 — 31 exposures (zg 20, zi 1, zr 10)Jun 2023 — 27 exposures (zg 18, zr 9)Aug 2023 — 2 exposures (zr)Nov 2023 — 12 exposures (zr)Dec 2023 — 9 exposures (zg 7, zr 2)

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 months that did have data. Hover a point for the running total and what it added.

Jan 1, 2023Mar 25, 2023Jun 17, 2023Sep 8, 2023Dec 1, 20231177991Jan 2023 — 8 added, 999 totalFeb 2023 — 19 added, 1,018 totalMar 2023 — 10 added, 1,028 totalApr 2023 — 68 added, 1,096 totalMay 2023 — 31 added, 1,127 totalJun 2023 — 27 added, 1,154 totalAug 2023 — 2 added, 1,156 totalNov 2023 — 12 added, 1,168 totalDec 2023 — 9 added, 1,177 total

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.

zg — 99 exposures (53% of 186) · Show only zgzr — 78 exposures (42% of 186) · Show only zrzi — 9 exposures (5% of 186) · Show only zi186exposureszg — 99 exposures (53% of 186) · Show only zgzg9953%zr — 78 exposures (42% of 186) · Show only zrzr7842%zi — 9 exposures (5% of 186) · Show only zizi95%

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 265 linked detections
Typical curve length
4 points
median over those objects
Typical revisit
1 d
median gap between consecutive points
Longest baseline
326.1 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.

under 1 hour — 50 gaps (20%)under 1 hour501–6 hours — 22 gaps (9%)1–6 hours226–24 hours — 46 gaps (19%)6–24 hours461–3 days — 53 gaps (21%)1–3 days533–10 days — 35 gaps (14%)3–10 days3510–30 days — 29 gaps (12%)10–30 days291–3 months — 7 gaps (3%)1–3 months73–12 months — 6 gaps (2%)3–12 months6over a year — 0 gaps (0%)over a year0

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 (91 points).

1 point — 7 objects (41%) · list them1 point72–4 — 2 objects (12%) · list them2–425–9 — 3 objects (18%) · list them5–9310–24 — 2 objects (12%) · list them10–24225–49 — 1 object (6%) · list it25–49150–99 — 2 objects (12%) · list them50–992100 or more — 0 objects (0%)100 or more0

Same data as JSON: /api/statistics?from=2023-01-01&to=2023-12-31