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
3,051–3,100 of 214,524 · All objects seen in the 7 nights
ObjectClassLast magRisePeakFirst seenLast seenNightsDetectionsRel.RA, DecPartner
ZTF ZTF18aagbezw BYDraV*18.79 r+0.118.782018-09-212026-09-29881.00123.1793, 15.5926
ZTF ZTF18aagbzsd AGNfaded r−0.718.992017-12-282026-09-29982571.00120.1920, 20.4978
ZTF ZTF18aagbzwr Seyfert2AT 2019pya18.70 r+0.318.662018-01-132026-09-2913151.00120.3806, 19.9808
ZTF ZTF18aagdwie QSO19.39 r+0.519.372018-11-032026-09-2918181.00126.4462, 18.2080
ZTF ZTF18aagigmg QSOfaded r−0.318.742018-11-032026-09-29781361.00121.5409, 22.2604
ZTF ZTF18aagiwkv RRLyrae19.06 r+0.318.942018-02-112026-09-2914161.00123.5534, 15.4717
ZTF ZTF18aagkdcx Unknownfaded r−0.317.122018-09-172026-09-2964791.00124.0976, 17.6116
ZTF ZTF18aagkggb Unknownfaded r−0.1—2019-01-292026-09-29331.00123.5905, 18.1763
ZTF ZTF18aagklae Unknown18.42 r+0.118.372018-01-112026-09-2923241.00123.6340, 18.1453
ZTF ZTF18aagnnam RSCVnV*faded r−0.116.782018-09-142026-09-2926341.00120.4295, 20.9324
ZTF ZTF18aagnpsy Unknown18.09 r+0.118.092018-11-032026-09-29110.81120.8121, 16.5734
ZTF ZTF18aagnqdv EclBinfaded r−0.2—2017-12-152026-09-29551.00122.5870, 18.1118
ZTF ZTF18aagnsdj Unknownfaded r−0.117.852019-12-022026-09-2929341.00121.5054, 16.4731
ZTF ZTF18aagnwdy Unknownfaded r−0.218.812019-01-282026-09-2917221.00121.6789, 16.2695
ZTF ZTF18aagortu Variable*faded r−0.216.952018-04-152026-09-2924291.00120.9188, 21.7278
ZTF ZTF18aagoshr Unknown17.92 r+0.117.102018-11-032026-09-2922261.00121.7013, 18.5335
ZTF ZTF18aagoxll Seyfert1AT 2019bzj17.87 r+0.317.052018-04-192026-09-29911831.00121.2198, 21.3473
ZTF ZTF18aagpeyq QSOfaded r−1.219.272018-02-182026-09-29922191.00120.4535, 17.7212
ZTF ZTF18aahnrgy EclBinfaded r−0.619.152017-12-152026-09-2912131.00122.7267, 20.4068
ZTF ZTF18aahnryb EclBinfaded r−0.218.332018-02-242026-09-2923311.00124.7028, 15.7399
ZTF ZTF18aalmiii ChemPec*faded r−0.216.992018-04-192026-09-2922271.00124.0272, 17.3139
ZTF ZTF18abujnje Unknownfaded r−0.218.472018-09-082026-09-2918211.00121.2907, 17.4923
ZTF ZTF18abvgjvh Seyfert1faded r−0.218.762018-09-112026-09-2932411.00122.7928, 17.6621
ZTF ZTF18abvgjvi QSO18.52 r+0.518.132018-09-112026-09-29641261.00122.7129, 17.6764
ZTF ZTF18abxbkwo EclBinfaded r−0.315.862018-02-242026-09-297111.00123.3626, 15.7137
ZTF ZTF18abxblam Unknown18.22 r+0.217.792018-09-172026-09-2946611.00126.7828, 17.4752
ZTF ZTF18abyysqx Unknownfaded r−0.216.372018-09-242026-09-2945681.00123.4521, 17.4297
ZTF ZTF18accnmcw QSOfaded r−0.118.442018-11-032026-09-2955741.00122.3735, 18.2679
ZTF ZTF18accnner Unknownfaded r−0.218.752018-11-032026-09-2928411.00122.4030, 15.6096
ZTF ZTF18accnnrb Seyfert1AT 2020xay19.01 r+0.118.802018-11-032026-09-2921221.00121.6054, 16.0796
ZTF ZTF18achcitf Unknown15.40 r+0.215.402017-12-052026-09-2917210.95120.2483, 22.2859
ZTF ZTF18achyxpc Unknown18.53 r+0.218.302018-11-122026-09-2931331.00124.2250, 16.0673
ZTF ZTF18aclnxso Unknownfaded r−0.118.542017-12-202026-09-2910111.00120.5087, 21.8244
ZTF ZTF18acpaydj Unknown14.99 r+0.214.992017-12-152026-09-2911110.83127.0178, 17.9917
ZTF ZTF18acsonzf Unknownfaded r−0.218.502018-12-032026-09-2936561.00123.1537, 18.4707
ZTF ZTF18adaymfo Unknownfaded r−0.2—2018-12-282026-09-29771.00121.6822, 19.5830
ZTF ZTF18adbgjdv Unknown17.96 r+0.217.792018-11-142026-09-2955881.00122.8628, 15.9691
ZTF ZTF18adbgnbv QSOfaded r−0.618.972018-11-082026-09-29811341.00126.2731, 17.8142
ZTF ZTF18adgdtxe EclBinfaded r−0.214.692017-12-052026-09-2923361.00120.2234, 20.1665
ZTF ZTF18adkbtan Seyfert1AGN18.88 r+0.217.702018-05-252026-09-2967971.00124.2131, 18.0472
ZTF ZTF19aadwxub ChemPec*faded r−0.115.012018-11-142026-09-2927361.00123.3757, 19.8208
ZTF ZTF19aaebunr Unknownfaded r−0.318.922017-12-142026-09-2935591.00121.6620, 17.6896
ZTF ZTF19aafctum Unknownfaded r−2.919.452018-12-292026-09-29691081.00126.9061, 16.4715
ZTF ZTF19aagkdqk Unknown19.36 r+0.118.892019-01-302026-09-29661.00120.8194, 17.9999
ZTF ZTF19aahfkxd Unknownfaded r−0.217.542018-11-122026-09-2928391.00121.4516, 16.0488
ZTF ZTF19aakxxfi Unknownfaded r−0.719.462019-01-282026-09-29771.00125.9298, 16.7517
ZTF ZTF19aceftqa Seyfert118.89 r+0.418.642018-01-132026-09-29811421.00126.4552, 17.5635
ZTF ZTF19acmbdmg Unknownfaded r−0.217.482019-11-012026-09-29841451.00121.3131, 19.6802
ZTF ZTF19acxxsgz Unknownfaded r−0.117.882019-04-292026-09-29781131.00121.5325, 19.6856
ZTF ZTF19acxxvzu QSO18.79 r+0.618.752018-12-192026-09-29952541.00120.6529, 19.4357