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
2,201–2,250 of 214,523 · All objects seen in the 7 nights
ObjectClassLast magRisePeakFirst seenLast seenNightsDetectionsRel.RA, DecPartner
ZTF ZTF17aaaizlx EclBinfaded r−0.317.052017-12-142026-09-29831621.00124.6484, 26.2432
ZTF ZTF17aaajdpo RRLyrae17.63 r+0.315.922017-12-082026-09-2956921.00125.0424, 26.7189
ZTF ZTF17aaajdqy EclBin18.84 r+0.218.502017-12-142026-09-2930331.00126.9136, 23.8772
ZTF ZTF17aaakuci EclBinfaded r−0.316.562017-12-082026-09-2914141.00125.4265, 25.3565
ZTF ZTF17aaaomps EclBin17.36 r+0.216.932017-12-082026-09-2941521.00125.7809, 22.7139
ZTF ZTF17aaapgyg EclBinfaded r−0.4—2018-01-142026-09-29341.00132.1487, 25.6550
ZTF ZTF17aaazhte Unknownfaded r−0.118.162017-12-172026-09-2911121.00126.5170, 24.8317
ZTF ZTF17aabohpy EclBin15.64 r+0.115.102017-12-152026-09-2931351.00129.9756, 23.3381
ZTF ZTF17aabrxfg RRLyrae18.08 r+0.317.312017-12-082026-09-2948581.00125.6654, 25.9887
ZTF ZTF17aabtgnp RRLyrae17.59 r+0.316.602017-12-082026-09-29761151.00126.9535, 27.3176
ZTF ZTF17aabtgyo RRLyrae18.59 r+0.317.272017-12-142026-09-2947731.00125.2108, 25.4720
ZTF ZTF17aabtkbd EclBinfaded r−0.318.402017-12-142026-09-2930331.00128.5500, 29.1342
ZTF ZTF17aabtkle EclBin18.27 r+0.218.082017-12-142026-09-2921261.00125.7101, 23.2793
ZTF ZTF17aabwoyy EclBin17.92 r+0.217.492017-12-082026-09-2952671.00129.4563, 22.9304
ZTF ZTF17aabwpbf EclBin16.84 r+0.316.252017-12-082026-09-2938511.00126.8843, 24.7824
ZTF ZTF17aabwpio EclBin17.28 r+0.317.222017-12-082026-09-2928381.00128.0619, 22.9064
ZTF ZTF17aadmivb EclBinfaded r−0.216.762017-10-192026-09-29711241.00125.0130, 29.7566
ZTF ZTF18aaabjni delSctV*faded r−0.317.842018-01-112026-09-2948621.00131.6152, 24.5881
ZTF ZTF18aaacbzs EclBinfaded r−0.417.652017-12-082026-09-2953701.00127.2705, 27.6250
ZTF ZTF18aaaccag EclBin17.74 r+0.317.312017-12-082026-09-2962891.00128.2924, 27.2636
ZTF ZTF18aaaccdt EclBinfaded r−0.216.382017-12-152026-09-2923331.00130.4122, 25.1826
ZTF ZTF18aaadbnb EclBin17.28 r+0.115.912017-12-152026-09-2931371.00130.9328, 23.7967
ZTF ZTF18aaagtme EclBinfaded r−0.215.152017-12-082026-09-2959701.00128.2599, 29.4721
ZTF ZTF18aaahbeo EclBin18.70 r+0.117.922018-02-072026-09-2934441.00126.3414, 26.2505
ZTF ZTF18aaailra EclBinfaded r−0.217.482017-12-142026-09-2945551.00125.5808, 27.4793
ZTF ZTF18aaaprwb EclBinfaded r−0.216.822017-12-082026-09-2943561.00127.1832, 24.0259
ZTF ZTF18aaastfc EclBin16.89 r+0.116.892017-12-142026-09-29880.99129.3348, 24.9757
ZTF ZTF18aaatjxy EclBinfaded r−0.115.932017-12-142026-09-2916191.00130.5226, 22.4186
ZTF ZTF18aaatkfa Unknown18.94 r+1.418.102018-02-072026-09-2948731.00132.1176, 22.5142
ZTF ZTF18aaaxhsz EclBinfaded r−0.117.282018-01-142026-09-2925261.00125.8236, 26.5723
ZTF ZTF18aaaxyxh EclBin19.33 r+0.319.332017-12-142026-09-2913131.00126.1359, 28.9270
ZTF ZTF18aaaxzbs EclBinfaded r−0.2—2017-12-142026-09-2927291.00126.3643, 26.5779
ZTF ZTF18aaazdhg EclBinfaded r−0.318.342018-01-132026-09-2915171.00128.0385, 28.9586
ZTF ZTF18aaazuuf EclBinfaded r−0.218.472017-12-152026-09-2928331.00131.3564, 25.5818
ZTF ZTF18aabjzjm EclBinfaded r−0.317.142017-12-152026-09-2919221.00132.0762, 24.6787
ZTF ZTF18aabqvgg Unknownfaded r−0.7—2018-02-242026-09-29111.00126.3525, 27.9498
ZTF ZTF18aabrwsc EclBinfaded r−1.217.352018-03-052026-09-2914241.00125.3919, 27.1301
ZTF ZTF18aaenvav Unknown17.70 r+0.116.972017-12-142026-09-2914151.00127.9292, 27.0777
ZTF ZTF18aaeogfj Unknownfaded r—13.702018-04-192026-09-29871160.95127.4493, 26.7729
ZTF ZTF18aaepluj Variable*faded r−0.118.502018-12-292026-09-29331.00128.2283, 26.3642
ZTF ZTF18aaexhep QSOfaded r−0.217.202017-12-172026-09-29711251.00126.9937, 23.5507
ZTF ZTF18aaeznkj Unknown17.02 r+0.117.022017-12-172026-09-29110.85126.1175, 23.3107
ZTF ZTF18aafacod QSOfaded r−0.518.272018-09-112026-09-291022601.00125.1009, 23.5807
ZTF ZTF18aafadhv QSO19.23 r+0.318.872020-10-152026-09-29821681.00124.8733, 23.3771
ZTF ZTF18aafadki Unknown19.28 r+0.419.232018-09-292026-09-2910101.00125.3516, 23.8002
ZTF ZTF18aafansc Solar System MPC19.11 r+0.419.112026-09-292026-09-29111.00131.6712, 25.3916
ZTF ZTF18aafaple QSO18.57 r+0.418.542018-11-052026-09-2963851.00128.3106, 27.8065
ZTF ZTF18aafaqqf QSO19.02 r+0.118.782019-02-122026-09-2930311.00128.0839, 24.5169
ZTF ZTF18aafawkn Variable*faded r−0.1—2018-02-242026-09-2914140.98125.4519, 27.1744
ZTF ZTF18aafboie Unknownfaded r−0.216.842018-02-092026-09-2966811.00125.5817, 27.3314