Transient Explorer

What am I looking at?

Every night the Rubin (LSST) and ZTF telescopes image the sky and flag anything that changed since last time: a supernova going off, a star flaring, an asteroid passing through. Each flag is an alert. The Fink broker classifies them, and this site shows what they are and where. Transients the two surveys miss, reported by others to the Transient Name Server, are here too.

Sources

  • ZTF and Rubin: objects the surveys alerted on. Each detection is an alert, with the broker's classification, a reliability score and three image cutouts.
  • TNS: transients reported to the Transient Name Server that neither survey alerted on, among them nearly every bright one south of −30°, which ZTF cannot see. Each detection is a report: the magnitudes reported to TNS (the discovery, and any later ones), each in its reporter's filter, then ATLAS's measurements (c and o bands) for two months while it is brighter than 19. Reported by names the surveys (ATLAS, GOTO, Pan-STARRS, …). When ZTF or Rubin later alerts on one, it becomes their object.
  • CBAT: reports on the Central Bureau's Transient Object Confirmation Page that neither the surveys nor TNS have, mostly bright Galactic novae (PNV J…) and dwarf novae in outburst (TCP J…). An object that matches a TOCP entry shows its designation.
  • A TNS type (SN Ia, Nova, AGN, …) decides an object's class whoever saw it; without one, the broker's label does.
  • An object is active while it has detections in the window. A TNS or CBAT object ATLAS does not measure (fainter than 19, older than two months, or not yet measured) is active only while the window holds its last report, so it leaves the short windows a week later.

Pages

  • Dashboard: how many alerts and objects arrived in a window, what kinds, where on the sky, and the brightest new supernova candidates.
  • Sky: the map. Most of what follows is about it.
  • Objects: the same objects as a table you can sort, filter by the broker's label or TNS type, and page through; click one for its light curve and images.
  • Tonight: a planner for your telescope. Pick your site and telescope, and it lists the supernovae, novae and new objects seen this week that are above your horizon while it is dark and bright enough to see, sorted by when each is best placed, with finder charts, a CSV export and a printable list.

Search

  • An object id (ZTF26abvkmbu, a Rubin id, or the first few characters), a TNS name (SN 2026abc), coordinates (35.71 -4.75 or 02:22:50 -04:45:00, add r=10' for a radius), a deep-drilling field (COSMOS), a class (SN Ia, EclBin) or any name astronomers use (M31).

On the map: zoom to go deeper

  • Whole sky (wider than 20°): a heatmap of how many objects were seen in each patch of sky.
  • Region (1°–20°): a finer heatmap plus numbered badges. The number is the count of objects, the color is their most common class, and a white ring means something new in the last night.
  • Objects (under 1°): one dot per object. A white ring means it was seen last night, and a white center means it has been detected only once so far. Click a dot for its light curve, classification and images.

Drag to pan, scroll or pinch to zoom, or click a badge to zoom into it.

Filters

  • Window: how far back to look, from last night to a year.
  • Active / new: objects detected in the window, or only those first seen in it.
  • Class: most alerts are solar-system objects (asteroids). Pick Non-Solar System to hide them and see what else is out there.
  • Brightness (≤ 20, ≤ 18, ≤ 16): only objects at least that bright. Smaller magnitudes are brighter. An object marked faded was last seen fainter than in the survey's reference image, so it has no brightness of its own and counts only under any mag.
  • History (2+ nights, …): only objects seen on several nights, which filters out one-off artifacts.

Observing from your site

  • Your site: an observatory from the list, or your latitude and longitude (typed, or Use my location). A position is rounded to half a degree, and the site is remembered in this browser only.
  • Object panel: when the object is up tonight, its altitude through the night with the moon, the next 60 nights, and a Finder chart with a link to AAVSO's comparison stars.
  • Objects: Visible from… keeps what is above your limit in tonight's dark window, with when and how high.
  • Sky: Observer… shades what is below your horizon at a time you pick; the counts do not change.

Dark means the sun more than 12° below the horizon (18° if you choose). Positions ignore refraction and precession, a few tenths of a degree: enough to plan, not to point.

Classes

  • SN candidate
  • AGN / nuclear
  • Variable star
  • Solar system
  • Cataloged
  • Unknown
  • Low reliability
  • Other

Data credits

Fink: ZTF and Rubin alerts: classifications, light curves and cutouts
Möller et al. 2021, MNRAS 501, 3272; ZTF (Bellm et al. 2019) and the Vera C. Rubin Observatory LSST.
Transient Name Server (TNS): names, types and discovery reports of transients from every survey
The IAU Transient Name Server, operated by the Weizmann Institute of Science; reports by the surveys named on each object.
CBAT: the Transient Object Confirmation Page: bright novae and other transients reported to the Central Bureau
Central Bureau for Astronomical Telegrams, Transient Object Confirmation Page (TOCP).
ATLAS: forced photometry of TNS objects, from the ATLAS forced-photometry server
Tonry et al. 2018, PASP 130, 064505; Smith et al. 2020, PASP 132, 085002; Shingles et al. 2021, TNS AstroNote 2021-7.
CDS, Strasbourg: sky imagery (HiPS), finder charts (hips2fits) and name resolution (Sesame)
This research has made use of the CDS services, Strasbourg Astronomical Observatory, France.

The data is refreshed nightly. Every view is a link: on the map the URL records the position, zoom, filters and selected object, so Copy link shares exactly what you see.

Made by jgriz

Objects

Objects
Source
Bucket
Clear
2,801–2,850 of 214,524 · All objects seen in the 7 nights
ObjectClassLast magRisePeakFirst seenLast seenNightsDetectionsRel.RA, DecPartner
ZTF ZTF18acrxodz Variable*faded r−0.1—2018-11-072026-09-2944761.00120.5730, -5.3421
ZTF ZTF18acrxohe Unknown16.47 r—16.022018-11-072026-09-2912141.00118.3143, -3.2966
ZTF ZTF18acsoshg EclBinfaded r−0.216.752018-11-072026-09-2934511.00118.9977, -3.8055
ZTF ZTF18acsosjd EclBinfaded r−0.4—2017-12-082026-09-2928401.00119.2169, -6.2601
ZTF ZTF18acsoskw EclBin18.07 r+0.217.652018-11-072026-09-29781111.00120.1374, -2.3292
ZTF ZTF18acsoskz EclBin18.55 r+0.117.532017-12-082026-09-2971961.00119.6509, -2.2351
ZTF ZTF18acsosmy EclBinfaded r−0.118.702017-12-082026-09-2942481.00118.2261, -3.8321
ZTF ZTF18acsosqp EclBinfaded r−0.218.532018-11-072026-09-2935411.00119.3782, -1.8607
ZTF ZTF18acsosyc EclBin18.89 r+0.218.482018-11-072026-09-2949671.00120.5148, -0.4606
ZTF ZTF18actdftm Unknownfaded r−0.1—2018-12-042026-09-29761691.00117.8245, -1.3873
ZTF ZTF18actedsx Unknown17.03 r+0.117.032018-04-022026-09-29111.00117.8470, -0.9549
ZTF ZTF18acuqrsd Unknown14.57 r+0.214.572018-11-172026-09-29220.84124.8752, -3.3463
ZTF ZTF18acuqujk EclBinfaded r−0.117.002018-11-072026-09-2943591.00119.2458, -5.9586
ZTF ZTF18acvvdqf Unknown17.73 r+0.117.092018-11-172026-09-2952921.00121.2519, -4.2891
ZTF ZTF18acvveqo Unknownfaded r−0.1—2018-12-132026-09-2922291.00118.0474, 0.3468
ZTF ZTF18acvvetd Variable*faded r−0.1—2018-12-132026-09-2920231.00119.1392, -4.1213
ZTF ZTF18acvvfno Unknown18.90 r+0.218.792018-11-172026-09-2912161.00119.7036, -3.6322
ZTF ZTF18acvvfsc EclBinfaded r−0.1—2018-11-172026-09-2910111.00119.0133, -2.4766
ZTF ZTF18acvvjce Unknown16.10 r+0.116.102018-11-202026-09-299100.90124.1971, -5.5218
ZTF ZTF18acvvjfr Star16.60 r+0.216.282018-11-172026-09-2952881.00119.9496, -5.9874
ZTF ZTF18acvvjpy EclBinfaded r−0.317.422018-11-072026-09-299111.00118.6582, -5.2361
ZTF ZTF18acvwhdl Unknownfaded r−0.1—2018-11-172026-09-2941481.00119.0137, -5.1602
ZTF ZTF18acvwhmz Unknownfaded r−0.317.912018-11-172026-09-29861551.00120.3246, 0.8140
ZTF ZTF18acvwhpw EclBinfaded r−0.2—2018-11-202026-09-2910131.00118.9058, -4.2302
ZTF ZTF18acvwhpx Unknown15.77 r+0.115.332018-12-132026-09-2943600.95119.2021, -4.2409
ZTF ZTF18acvwhpy Unknownfaded r−0.1—2018-12-132026-09-29450.99118.9182, -4.3673
ZTF ZTF18acvwhqj RRLyrae18.58 r+0.418.342018-11-072026-09-2937521.00118.6848, -2.2366
ZTF ZTF18acvwhqo EclBinfaded r−0.217.562018-11-072026-09-2913141.00117.9840, -4.1088
ZTF ZTF18acvwibh Unknownfaded r−0.1—2018-11-172026-09-2932391.00118.8269, -3.4582
ZTF ZTF18acwwjvh Star18.38 r+0.117.552018-12-162026-09-29461.00124.8805, -5.4393
ZTF ZTF18acwxics Unknown17.41 r+0.116.902018-11-172026-09-29751201.00119.4006, -2.4212
ZTF ZTF18aczdmej EclBinfaded r−0.216.642017-12-082026-09-2943471.00123.3432, -2.9037
ZTF ZTF18aczdnad EclBinfaded r−0.119.112018-11-172026-09-2932391.00118.8622, -2.4065
ZTF ZTF18aczeder Unknownfaded r−0.1—2018-11-072026-09-29881.00118.8085, -3.3367
ZTF ZTF18adayjfs EclBinfaded r−0.1—2018-12-282026-09-29451.00119.2117, -5.9917
ZTF ZTF18adayjmb BYDraV*16.68 r+0.116.512018-11-072026-09-2918201.00121.9002, -4.1079
ZTF ZTF18adayjwo EclBin18.84 r+0.218.742018-12-282026-09-2931381.00118.3076, -5.9124
ZTF ZTF18adayjxa Starfaded r−0.216.432018-11-202026-09-29721141.00117.9520, 0.5503
ZTF ZTF18adaylbk EclBin18.57 r+0.118.572018-11-282026-09-2917191.00120.4892, -5.7991
ZTF ZTF18adazvbc Unknown16.98 r+0.116.982018-12-282026-09-29441.00118.7291, -1.9708
ZTF ZTF18adbhssd EmLine*16.67 r+0.216.232018-11-102026-09-29721141.00121.8211, -4.3866
ZTF ZTF18adbhtcq Unknownfaded r−0.2—2018-11-072026-09-29550.98119.1779, -0.5810
ZTF ZTF18adbhtki Unknown19.12 r+0.219.122018-12-292026-09-2912151.00118.0308, -2.0411
ZTF ZTF18adbpmvl EclBin_Candidate16.43 r+0.116.432018-01-112026-09-2928341.00118.9437, 0.8893
ZTF ZTF18adpaatu EclBin18.54 r+0.218.202018-11-072026-09-2953611.00118.7215, 0.6240
ZTF ZTF18adpacck EclBinfaded r−0.218.062018-11-102026-09-2934351.00123.0531, -5.2070
ZTF ZTF18adpaccm EclBin18.39 r+0.217.872018-11-072026-09-2925301.00122.8576, -5.2913
ZTF ZTF18adpacdf EclBin16.43 r+0.216.342018-11-102026-09-2940471.00122.5771, -3.8918
ZTF ZTF18adpacdg Unknownfaded r−0.1—2018-11-102026-09-2919250.99122.5358, -4.2971
ZTF ZTF18adpacdj Unknown18.45 r+0.118.082018-11-102026-09-2939461.00122.7311, -3.9860