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
2,001–2,050 of 214,471 · All objects seen in the 7 nights
ObjectClassLast magRisePeakFirst seenLast seenNightsDetectionsRel.RA, DecPartner
ZTF ZTF19aamgcgb Unknown14.36 r+0.214.002018-12-172026-09-2917211.00123.3903, -6.8685
ZTF ZTF19aamgciv EclBin17.10 r+0.116.732018-11-072026-09-29781.00122.7057, -10.6562
ZTF ZTF19aananjv Unknownfaded r−0.2—2019-03-202026-09-29711491.00121.6626, -10.6552
ZTF ZTF19aaneixt Unknown18.79 r+0.218.792018-11-072026-09-2910101.00125.3313, -12.4719
ZTF ZTF19aanqsyn Unknown17.67 r+0.117.302018-11-072026-09-2910111.00126.2184, -12.7389
ZTF ZTF19aanqtdf Unknown17.50 r+3.517.502019-03-302026-09-29111.00122.3309, -12.9127
ZTF ZTF19aapjigk Unknown17.64 r+0.117.642019-04-092026-09-29110.55122.3263, -13.4151
ZTF ZTF19aapubmi Star17.68 r+0.117.602019-01-122026-09-29771.00125.5659, -11.6097
ZTF ZTF19aaqgrdy EclBin17.39 r+0.217.392018-11-072026-09-29331.00122.3582, -12.5719
ZTF ZTF19aaqgrgr BLLacfaded r−0.4—2019-04-112026-09-2947761.00124.1133, -13.1980
ZTF ZTF19aarrync Unknown18.33 r+0.118.192018-11-172026-09-2939451.00123.5549, -12.1014
ZTF ZTF19aaswtlb Star16.31 r+0.116.262018-11-172026-09-2952911.00121.4875, -11.0222
ZTF ZTF19aasxmxt EclBinfaded r−0.2—2017-12-082026-09-29220.99127.2253, -11.3117
ZTF ZTF19aatwjmp EclBinfaded r−0.419.702019-03-162026-09-29661.00122.4108, -7.8144
ZTF ZTF19aatwjqd Unknown18.47 r+0.218.322019-05-052026-09-2940491.00122.3908, -6.6612
ZTF ZTF19accczfq Unknownfaded r−0.2—2019-10-022026-09-2956761.00123.7156, -9.6203
ZTF ZTF19accczga Unknown18.08 r+0.217.932019-01-262026-09-29822051.00125.3872, -13.3984
ZTF ZTF19accdeds EclBinfaded r−0.117.392017-12-142026-09-2938431.00123.4632, -7.0215
ZTF ZTF19accdepb Unknownfaded r−0.2—2019-02-092026-09-2942651.00122.8279, -12.8137
ZTF ZTF19acdacce Unknownfaded r−0.1—2019-01-042026-09-2922271.00126.7198, -10.7275
ZTF ZTF19acdacjy Unknown18.82 r+0.118.802019-10-052026-09-2913171.00126.4876, -12.1939
ZTF ZTF19acekbiz Unknown17.32 r+0.217.312018-11-172026-09-2948661.00121.4331, -11.4028
ZTF ZTF19acekbxw Unknownfaded r−0.1—2018-12-172026-09-2951671.00126.3474, -10.0768
ZTF ZTF19acekcne Star17.91 r+0.117.112019-01-082026-09-2918201.00124.7467, -8.0703
ZTF ZTF19acewceb Unknownfaded r−0.1—2019-01-042026-09-2950801.00121.4702, -12.3509
ZTF ZTF19acgeazq LongPeriodV*15.24 r+0.115.242018-11-072026-09-29110.16125.0112, -8.4775
ZTF ZTF19achahww Unknown15.65 r+0.215.002018-11-072026-09-29631101.00121.6241, -8.5548
ZTF ZTF19aciezap EclBinfaded r−0.4—2018-12-282026-09-29111.00125.1965, -13.0602
ZTF ZTF19acifsrn Unknown16.50 r+0.216.502018-11-172026-09-29990.98123.5469, -11.4342
ZTF ZTF19acjnupa Unknown16.50 r+0.116.502018-11-272026-09-29771.00122.0711, -12.4901
ZTF ZTF19aclhnoz Unknown18.60 r+0.118.442019-10-312026-09-2928351.00125.6392, -10.3146
ZTF ZTF19acnpqqf Unknown18.96 r+0.118.612019-11-032026-09-2959871.00121.4348, -9.5579
ZTF ZTF19acnpqsw Variable*faded r−0.1—2019-11-032026-09-2929351.00123.6029, -9.2257
ZTF ZTF19acnpqwu Star18.31 r+0.218.122018-11-272026-09-2927371.00121.8151, -11.2154
ZTF ZTF19acnqhnd Unknownfaded r−0.1—2019-01-122026-09-2952751.00122.9069, -7.5002
ZTF ZTF19acucdwp Unknown18.16 r+0.218.062019-11-192026-09-2944471.00126.5158, -10.5475
ZTF ZTF19acvtqws EclBin17.66 r+0.117.132017-12-082026-09-29781.00122.2147, -13.1063
ZTF ZTF19acymunk Unknownfaded r−0.1—2018-11-172026-09-2919211.00125.2552, -11.2176
ZTF ZTF19acymuse Unknown18.19 r+0.018.192019-12-142026-09-29111.00121.8661, -12.9973
ZTF ZTF19adfmjbv Unknown18.83 r+0.118.052018-11-272026-09-2943681.00121.7972, -10.8254
ZTF ZTF19adgomac Unknownfaded r−0.1—2019-02-242026-09-29110.96124.9882, -10.3715
ZTF ZTF20aaborbw Unknown17.68 r+0.217.682020-01-022026-09-2910101.00124.1936, -10.1601
ZTF ZTF20aakkuyk EclBin16.08 r+0.116.082017-12-082026-09-29550.99122.5866, -8.1259
ZTF ZTF20aalmvtz Unknownfaded r−0.2—2019-03-162026-09-29721141.00125.7011, -10.5029
ZTF ZTF20aamrsfw Variable*faded r−0.2—2017-12-082026-09-2937451.00122.5678, -7.7177
ZTF ZTF20aanonjo Unknownfaded r−0.1—2020-02-152026-09-2911151.00122.8090, -11.0773
ZTF ZTF20aaoqwqs Unknownfaded r−0.2—2020-02-192026-09-2916191.00122.8127, -12.6028
ZTF ZTF20aciualo Unknownfaded r−0.1—2020-10-132026-09-2946601.00122.5827, -8.5817
ZTF ZTF20aciualv Unknown17.69 r+0.217.692018-12-172026-09-29221.00125.4366, -10.3323
ZTF ZTF20aciubkh Unknownfaded r−0.1—2018-11-272026-09-29330.99122.3920, -11.8496