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
1,851–1,900 of 256,282 · All objects seen in the 7 nights
ObjectClassLast magRisePeakFirst seenLast seenNightsDetectionsRel.RA, DecPartner
ZTF ZTF18acljibv LINERfaded r−0.1—2018-11-042026-09-26110.99124.0199, 23.1338
ZTF ZTF18acmscbg Unknown18.08 r+0.118.082018-11-142026-09-26110.58125.5710, 19.7579
ZTF ZTF18acmsfue Unknown17.56 r+0.117.562018-11-142026-09-26110.38124.9716, 19.7666
ZTF ZTF18acmsirj RGB*15.23 r+0.115.232018-11-142026-09-26110.61124.6223, 19.7580
ZTF ZTF18acmsqac Unknown16.22 r+0.116.222018-11-142026-09-26110.02125.6615, 19.8838
ZTF ZTF18acmstvx Unknown19.02 r+0.119.022017-12-172026-09-26110.97126.8813, 18.9311
ZTF ZTF18acmsuaz Unknown19.07 r+0.119.072019-01-292026-09-26110.76126.9093, 19.1809
ZTF ZTF18acsuwdg Starfaded r−0.216.172018-12-032026-09-26451.00123.9114, 19.0767
ZTF ZTF18aczcujm EclBin16.60 r+0.216.602018-11-052026-09-26221.00123.5980, 20.7860
ZTF ZTF18adoksjy Unknownfaded r−0.1—2017-12-172026-09-26110.96127.3193, 19.5436
ZTF ZTF19aagkxha Unknown18.94 r+0.118.942019-01-302026-09-26220.98123.2657, 19.7767
ZTF ZTF19acbvbvk QSO18.79 r+0.518.572018-11-052026-09-268161.00124.0728, 24.3074
ZTF ZTF19acbvbzu BLLacfaded r−1.017.932018-11-052026-09-266111.00125.8531, 22.3842
ZTF ZTF19acewaaf Star17.30 r+0.117.152018-11-052026-09-26230.98124.0086, 20.9425
ZTF ZTF19acrrpru Unknownfaded r−0.1—2019-11-112026-09-26110.96123.3391, 23.0436
ZTF ZTF19addlswx Variable*16.34 r+0.216.342018-11-102026-09-26110.99124.2207, 20.8363
ZTF ZTF20aahcfza QSO19.15 r+0.318.982020-01-232026-09-26651021.00127.0656, 19.5023
ZTF ZTF20aakxwsp Unknown17.66 r+0.217.662020-01-292026-09-26330.97123.5577, 24.1826
ZTF ZTF26abrhnfb UnknownSN II17.52 r+4.317.352026-08-302026-09-26221.00127.0300, 20.2730
ZTF ZTF26abxsviv Solar System MPC15.39 r—15.392021-11-222026-09-26111.00124.7981, 22.7916
ZTF ZTF26abxsviw Solar System MPC16.64 r—16.642026-09-262026-09-26111.00125.0323, 22.6606
ZTF ZTF26abxsvix Solar System MPC18.87 r—18.872026-09-262026-09-26111.00124.8851, 22.7348
ZTF ZTF26abxsviz Solar System MPC19.04 r—19.042026-09-262026-09-26111.00124.8404, 22.9123
ZTF ZTF26abxsvja Solar System MPC19.16 r—19.162026-09-262026-09-26111.00125.0651, 23.1749
ZTF ZTF26abxsvkf Solar System MPC16.32 r—16.322026-09-262026-09-26111.00125.8925, 20.1707
ZTF ZTF26abxsvqk Solar System MPC18.09 r—18.092026-09-262026-09-26111.00122.6573, 20.3570
ZTF ZTF26abxsvql Solar System MPC19.05 r—19.052026-09-262026-09-26111.00123.0145, 19.8901
ZTF ZTF26abxsvtx Solar System MPC19.01 r—19.012026-09-262026-09-26111.00124.0699, 19.5603
ZTF ZTF26abxsvty Solar System MPC18.89 r—18.892026-09-262026-09-26111.00123.7426, 19.5381
ZTF ZTF26abxsvtz Solar System MPC19.12 r—19.122026-09-262026-09-26111.00124.0673, 19.2433
ZTF ZTF26abxsvua Solar System MPC19.11 r—19.112026-09-262026-09-26111.00124.0173, 19.4997
ZTF ZTF26abxsvvh Solar System MPC17.47 r—17.472026-09-262026-09-26111.00125.8204, 23.4222
ZTF ZTF26abxsvvk Solar System MPC17.97 r—17.972026-09-262026-09-26111.00125.9199, 23.1803
ZTF ZTF26abxsvvn Solar System MPC18.13 r—18.132026-09-262026-09-26111.00125.4666, 22.6737
ZTF ZTF26abxsvvs Solar System MPC18.48 r—18.482026-09-262026-09-26111.00125.8506, 23.4820
ZTF ZTF26abxsvvt Solar System MPC18.71 r—18.712026-09-262026-09-26111.00126.3056, 23.2725
ZTF ZTF26abxsvvu Solar System candidate18.90 r—18.902026-09-262026-09-26110.96125.5032, 22.6592
ZTF ZTF26abxsvvv Solar System MPC18.96 r—18.962026-09-262026-09-26111.00125.5251, 22.9517
ZTF ZTF26abxswag Solar System MPC18.32 r—18.322026-09-262026-09-26111.00122.6808, 23.1652
ZTF ZTF26abxswan Solar System MPC18.76 r—18.762026-09-262026-09-26111.00122.4812, 23.1805
ZTF ZTF26abxswap Solar System MPC19.26 r—19.262023-09-112026-09-26110.98123.3218, 22.6757
ZTF ZTF26abxswbn Solar System MPC18.69 r—18.692026-09-262026-09-26111.00127.0290, 22.2259
ZTF ZTF26abxswbo Solar System MPC18.98 r—18.982026-09-262026-09-26111.00126.9326, 21.9447
ZTF ZTF26abxswbp Solar System MPC18.70 r—18.702026-09-262026-09-26110.98128.6757, 21.2097
ZTF ZTF26abxswed Solar System MPC17.87 r—17.872026-09-262026-09-26111.00128.0932, 21.1568
ZTF ZTF26abxswee Solar System MPC18.39 r—18.392019-05-032026-09-26111.00127.6902, 21.3077
ZTF ZTF26abxswef Solar System MPC18.86 r—18.862026-09-262026-09-26110.99128.0379, 21.4501
ZTF ZTF26abxsweg Solar System MPC18.77 r—18.772026-09-262026-09-26111.00128.0709, 21.4154
ZTF ZTF26abxswfc Solar System MPC18.06 r—18.062026-09-262026-09-26111.00124.1216, 22.9634
ZTF ZTF26abxswfe Solar System MPC19.39 r—19.392026-09-262026-09-26110.96123.4935, 22.6800