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
1,951–2,000 of 256,282 · All objects seen in the 7 nights
ObjectClassLast magRisePeakFirst seenLast seenNightsDetectionsRel.RA, DecPartner
ZTF ZTF17aaapjdp RRLyraefaded r−0.218.322017-12-152026-09-2615181.00121.8656, 2.4918
ZTF ZTF17aabtiev RRLyraefaded r−0.217.802017-12-142026-09-2649541.00125.5105, -1.5887
ZTF ZTF17aabtldc EclBinfaded r−0.216.872017-12-152026-09-26881721.00124.9108, -2.4592
ZTF ZTF17aabwjvx EclBin15.81 r+0.114.962017-12-082026-09-2618211.00121.4351, -1.7930
ZTF ZTF17aabwjvz RRLyraefaded r−0.416.722017-12-082026-09-2660861.00123.7148, -0.0808
ZTF ZTF17aabwljo RRLyrae16.67 r+0.115.302017-12-082026-09-2655881.00120.2209, -2.5283
ZTF ZTF18aaabhde EclBin17.81 r+0.217.212018-01-112026-09-2637421.00119.7611, 2.1009
ZTF ZTF18aaacexw SB*faded r−0.114.712018-01-112026-09-2642691.00119.7152, 3.7609
ZTF ZTF18aaacgoc EclBin15.39 r+0.114.432018-01-112026-09-26681001.00119.2763, 1.2887
ZTF ZTF18aaacwhd RRLyraefaded r−0.614.612017-12-082026-09-26791211.00119.0221, 4.2577
ZTF ZTF18aabisbq EclBin16.98 r+0.116.092017-12-142026-09-2632451.00120.9768, 2.2892
ZTF ZTF18aabiscy EclBin17.73 r+0.117.352017-12-152026-09-2635491.00121.0082, 1.2966
ZTF ZTF18aabjdia EclBinfaded r−0.319.052018-01-112026-09-2624291.00120.6658, 4.1062
ZTF ZTF18aabjmdh Unknown19.11 r+0.118.562018-01-132026-09-2629451.00121.1561, 1.4309
ZTF ZTF18acexxca EclBinfaded r−0.418.512017-12-082026-09-2627331.00124.1550, 0.4125
ZTF ZTF18acexxhi EclBin16.95 r+0.216.952018-11-072026-09-2642501.00123.5210, 0.1407
ZTF ZTF18acexxhk EclBin17.82 r+0.117.172017-12-082026-09-2651681.00124.0970, 0.0504
ZTF ZTF18achdjmp Unknown18.47 r+0.118.212018-11-082026-09-26661.00124.6375, 0.4297
ZTF ZTF18achdjov EclBinfaded r−0.318.022018-11-102026-09-2648631.00125.5325, -0.1653
ZTF ZTF18achdjqi EclBin18.54 r+0.318.252017-12-082026-09-2652741.00123.1199, -2.0349
ZTF ZTF18achdjqo EclBinfaded r−0.218.132018-11-072026-09-2644561.00119.7730, -0.3813
ZTF ZTF18achdjru AGB*faded r−0.213.832018-11-072026-09-2637411.00122.9155, -0.3213
ZTF ZTF18achymrg EclBinfaded r−0.318.052018-11-072026-09-2639491.00124.7940, -2.3628
ZTF ZTF18achyndw EclBinfaded r−0.116.072018-11-072026-09-2637411.00126.2493, -1.2600
ZTF ZTF18achypyv Type2Cepfaded r−0.215.162017-12-162026-09-2656971.00124.9764, -1.4539
ZTF ZTF18achyryn RSCVnV*16.48 r+0.216.212017-12-182026-09-26771241.00125.7340, -0.5921
ZTF ZTF18achysaw Unknown18.51 r+0.117.662017-12-142026-09-2659841.00125.9569, -0.4077
ZTF ZTF18achywnf EclBinfaded r−0.218.102018-11-122026-09-2641651.00124.8179, -0.4626
ZTF ZTF18aclpnog Unknownfaded r−0.1—2019-01-082026-09-26111.00125.2274, -2.4366
ZTF ZTF18aclpznb Unknown16.58 r+0.216.392018-11-132026-09-2649591.00122.4834, -0.4622
ZTF ZTF18aclriaq Unknownfaded r−0.116.562018-11-172026-09-2641531.00120.0864, 0.6285
ZTF ZTF18acmatep RRLyraefaded r−0.317.572018-11-102026-09-2653741.00124.2877, -1.1681
ZTF ZTF18acmatmr EclBinfaded r−0.2—2018-11-122026-09-26111.00125.9991, -0.5980
ZTF ZTF18acnnsnd EclBinfaded r−0.318.892017-12-082026-09-2637501.00121.9415, -0.2887
ZTF ZTF18acnnsvd RRLyrae18.23 r+0.218.072017-12-082026-09-2641471.00121.5058, -1.2786
ZTF ZTF18acnnszj Starfaded r−0.2—2018-11-162026-09-26881.00124.6442, -1.6564
ZTF ZTF18acnntef RRLyraefaded r−0.316.822017-12-082026-09-26691061.00119.1704, -0.8359
ZTF ZTF18acnntfe EclBin18.18 r+0.217.722018-11-072026-09-2655861.00121.9909, -2.3949
ZTF ZTF18acpdbyn EclBin14.55 r+0.214.332017-12-142026-09-2626311.00125.2492, 0.5171
ZTF ZTF18acpdbyo EclBinfaded r−0.216.622017-12-162026-09-2640491.00125.2644, 0.5256
ZTF ZTF18acpdomx EclBinfaded r−0.418.612018-11-072026-09-2619221.00120.5033, -2.1387
ZTF ZTF18acppaeu Unknown17.39 r+0.217.392018-11-172026-09-2627311.00121.7759, -1.7039
ZTF ZTF18acppasy EclBinfaded r−0.115.302018-11-102026-09-2634351.00124.7360, -2.4873
ZTF ZTF18acpupkg RSCVnV*faded r−0.318.452018-11-192026-09-2631421.00122.5287, -1.9445
ZTF ZTF18acpwljt Unknown15.29 r+0.114.862018-11-192026-09-2655821.00122.0137, -1.3956
ZTF ZTF18acpwlkh Unknown18.46 r+0.116.482018-11-072026-09-2634441.00121.1819, -1.4138
ZTF ZTF18acqkwzx Mira13.69 r+1.413.452018-11-172026-09-26811371.00125.7932, -1.8905
ZTF ZTF18acrvglc EclBin18.50 r+0.117.612018-01-112026-09-26691011.00119.7389, 1.1799
ZTF ZTF18acrvhft Variable*18.13 r+0.117.952018-01-112026-09-2611131.00119.2890, 4.3304
ZTF ZTF18acrxmqp Unknown17.61 r+0.117.612018-11-282026-09-2654751.00119.5129, 3.1823