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
2,301–2,350 of 214,523 · All objects seen in the 7 nights
ObjectClassLast magRisePeakFirst seenLast seenNightsDetectionsRel.RA, DecPartner
ZTF ZTF20acxxrti Unknownfaded r−0.319.042019-11-012026-09-2962891.00131.4615, 24.6533
ZTF ZTF21aaetakp Unknown18.82 r+0.118.822018-11-122026-09-29110.92126.7832, 28.5782
ZTF ZTF23abbmadh Unknown17.70 r+0.217.702020-01-032026-09-29110.00128.0017, 29.4646
ZTF ZTF23abmrjvk Unknown19.46 r+2.419.382023-06-102026-09-2958921.00130.9159, 25.5905
ZTF ZTF24aaeyxvg EclBin14.86 r+0.214.852017-12-152026-09-2922241.00130.5001, 24.1165
ZTF ZTF24abxitnc EclBinfaded r−0.318.442017-12-142026-09-29331.00132.2510, 22.7811
ZTF ZTF25aaniwva Unknown13.69 r—13.632024-05-112026-09-2967991.00127.4465, 26.7714
ZTF ZTF26abyamon Solar System MPC18.48 r—18.482026-09-292026-09-29111.00126.8644, 23.9911
ZTF ZTF26abyamoo Solar System MPC18.70 r—18.702026-09-292026-09-29111.00126.9559, 23.2847
ZTF ZTF26abyamop Solar System MPC19.46 r—19.462026-09-292026-09-29111.00127.4068, 24.0011
ZTF ZTF26abyamrb Solar System MPC18.30 r—18.302026-09-292026-09-29111.00125.6260, 28.9388
ZTF ZTF26abyamrc Solar System MPC18.42 r—18.422026-09-292026-09-29111.00125.9214, 28.4416
ZTF ZTF26abyamrd Solar System MPC18.87 r—18.872026-09-292026-09-29111.00125.5808, 28.7838
ZTF ZTF26abyamsc Solar System MPC17.44 r—17.442026-09-292026-09-29111.00126.7756, 23.2243
ZTF ZTF26abyamsd Solar System MPC17.92 r—17.922026-09-292026-09-29111.00127.1414, 22.9536
ZTF ZTF26abyamvp Solar System MPC17.32 r—17.322026-09-292026-09-29111.00131.6227, 24.7837
ZTF ZTF26abyamvq Solar System MPC18.74 r—18.742026-09-292026-09-29111.00131.5831, 24.9801
ZTF ZTF26abyamyv Solar System MPC16.34 r—16.342026-09-292026-09-29111.00131.1492, 25.8272
ZTF ZTF26abyamzl Solar System MPC18.31 r—18.312026-09-292026-09-29111.00126.0978, 24.6288
ZTF ZTF26abyamzm Solar System MPC19.46 r—19.462026-09-292026-09-29111.00126.4553, 25.1483
ZTF ZTF26abyanaz Solar System MPC18.03 r—18.032026-09-292026-09-29111.00127.7458, 25.1203
ZTF ZTF26abyanba Solar System MPC19.32 r+3.519.322026-09-292026-09-29110.99128.4531, 25.0219
ZTF ZTF26abyancd Solar System MPC16.77 r—16.772026-09-292026-09-29111.00128.4132, 25.9991
ZTF ZTF26abyance Solar System MPC18.94 r—18.942026-09-292026-09-29111.00127.5724, 25.2460
ZTF ZTF26abyancm Solar System MPC16.27 r—16.272026-09-292026-09-29111.00127.9805, 23.0972
ZTF ZTF26abyancn Solar System MPC17.94 r—17.942026-09-292026-09-29111.00128.4810, 22.4526
ZTF ZTF26abyanco Solar System MPC18.56 r—18.562026-09-292026-09-29111.00128.5492, 22.5027
ZTF ZTF26abyancp Solar System MPC18.62 r—18.622026-09-292026-09-29111.00128.2815, 22.5613
ZTF ZTF26abyancr Solar System MPC19.23 r—19.232026-09-292026-09-29110.99127.8740, 22.4889
ZTF ZTF26abyands Solar System MPC18.37 r—18.372026-09-292026-09-29111.00131.8462, 24.8233
ZTF ZTF26abyanes Solar System MPC18.58 r—18.582026-09-292026-09-29111.00127.9201, 27.1201
ZTF ZTF26abyanet Solar System MPC18.69 r—18.692026-09-292026-09-29111.00127.7569, 27.2472
ZTF ZTF26abyaneu Solar System MPC18.60 r—18.602026-09-292026-09-29111.00128.2699, 27.3663
ZTF ZTF26abyaney Solar System MPC19.00 r—19.002026-09-292026-09-29111.00129.9938, 24.8706
ZTF ZTF26abyanez Solar System MPC19.06 r—19.062026-09-292026-09-29111.00130.0284, 24.5069
ZTF ZTF26abyanff Solar System MPC18.84 r—18.842026-09-292026-09-29110.99129.8802, 23.5957
ZTF ZTF26abyanfg Solar System MPC18.92 r—18.922026-09-292026-09-29111.00129.7203, 23.9018
ZTF ZTF26abyanfi Solar System MPC19.52 r—19.522026-09-292026-09-29111.00126.9257, 26.7787
ZTF ZTF26abyanfn Solar System MPC17.53 r—17.532026-09-292026-09-29111.00129.6438, 23.5016
ZTF ZTF26abyanfq Solar System MPC19.46 r—19.462026-09-292026-09-29110.93129.3430, 23.8380
ZTF ZTF26abyango Solar System MPC17.68 r—17.682026-09-292026-09-29111.00125.5882, 27.7795
ZTF ZTF26abyangz Solar System MPC14.94 r—14.942026-09-292026-09-29111.00131.9752, 25.8484
ZTF ZTF26abyanhm Solar System MPC17.39 r+4.817.392026-09-292026-09-29111.00125.4725, 22.7192
ZTF ZTF26abyanhn Solar System MPC18.95 r—18.952026-09-292026-09-29111.00125.6038, 22.7355
ZTF ZTF26abyanhp Solar System MPC19.12 r—19.122026-09-292026-09-29111.00129.4291, 24.7450
ZTF ZTF26abyanhq Solar System MPC19.46 r—19.462026-09-292026-09-29111.00129.1777, 25.1821
ZTF ZTF26abyanjz Solar System MPC19.59 r—19.592026-09-292026-09-29110.99129.3341, 25.2730
ZTF ZTF26abyanld Solar System MPC18.08 r—18.082026-09-292026-09-29111.00125.4373, 24.9596
ZTF ZTF26abyanle Solar System MPC14.35 r—14.352026-09-292026-09-29110.96128.5774, 24.1002
ZTF ZTF26abyanlh Solar System MPC18.55 r—18.552026-09-292026-09-29111.00125.2762, 24.6761