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
2,651–2,700 of 214,524 · All objects seen in the 7 nights
ObjectClassLast magRisePeakFirst seenLast seenNightsDetectionsRel.RA, DecPartner
ZTF ZTF18achdjnl EclBin_Candidatefaded r−0.117.602018-11-072026-09-2913151.00123.0640, -4.2313
ZTF ZTF18achdjnn EclBinfaded r−0.1—2018-11-102026-09-2916171.00122.9514, -4.2420
ZTF ZTF18achdjof EclBin17.74 r+0.117.502018-11-072026-09-2920211.00122.6917, -5.0564
ZTF ZTF18achdjpp Starfaded r−0.1—2018-11-102026-09-2913161.00122.4439, -4.3466
ZTF ZTF18achdjpu **faded r−0.1—2017-12-082026-09-2913130.95121.2181, 0.6250
ZTF ZTF18achdjpz EclBinfaded r−0.218.152018-11-072026-09-2943511.00121.0772, 0.6706
ZTF ZTF18achdjqj AGB*_Candidatefaded r−0.315.262018-11-072026-09-2940521.00119.9018, -0.0484
ZTF ZTF18achdjql Unknownfaded r−0.119.422018-11-072026-09-29991.00120.0720, -0.2536
ZTF ZTF18achdjqx EclBin17.50 r+0.217.362017-12-082026-09-2957711.00122.5027, -2.9771
ZTF ZTF18aclqivt Unknown16.16 r+0.116.012018-11-262026-09-2937391.00118.6572, 0.4725
ZTF ZTF18aclqkwj Unknownfaded r−0.118.642018-01-112026-09-2925321.00119.3678, 0.8366
ZTF ZTF18aclqqtg Unknown17.03 r+0.116.222018-11-072026-09-29691061.00120.3186, -0.4907
ZTF ZTF18aclrhiq LongPeriodV*faded r−0.1—2018-11-132026-09-2928401.00120.3783, 0.7038
ZTF ZTF18aclrhwc Star17.56 r+0.116.332018-01-112026-09-2932431.00119.7854, 0.9296
ZTF ZTF18acmatnk Mira11.92 r+1.89.872018-11-132026-09-2954631.00119.9122, 0.5078
ZTF ZTF18acmatnm EclBinfaded r−0.216.802017-12-082026-09-2920221.00120.2102, 0.3635
ZTF ZTF18acmatnu EclBin18.40 r+0.417.892018-01-112026-09-29751591.00119.6062, 1.0323
ZTF ZTF18acmatnz EclBin13.68 r+0.313.302018-11-102026-09-2916160.98118.0916, -1.2904
ZTF ZTF18acmatol EclBinfaded r−0.518.032018-11-072026-09-2965881.00118.3854, -0.9809
ZTF ZTF18acmatpi EclBinfaded r−0.1—2018-11-132026-09-29110.89122.3827, -2.8349
ZTF ZTF18acmattt Unknown17.58 r+0.117.192018-11-072026-09-2963851.00119.3636, -1.5101
ZTF ZTF18acmatua EclBinfaded r−0.117.542017-12-082026-09-2913141.00119.4002, -1.3300
ZTF ZTF18acmatuy RRLyrae16.85 r+0.113.842018-11-072026-09-2969881.00118.2732, -0.3670
ZTF ZTF18acmaugg EclBinfaded r−0.417.962017-12-082026-09-2960841.00121.5638, -4.1523
ZTF ZTF18acnnspw RRLyrae18.36 r+0.117.132017-12-082026-09-2963871.00117.8092, -0.6205
ZTF ZTF18acnntaf EclBinfaded r−0.218.632018-11-072026-09-2951611.00123.6279, -3.8565
ZTF ZTF18acnntch EclBinfaded r−0.417.272018-11-072026-09-2928361.00120.9707, 0.5634
ZTF ZTF18acnnteg Unknownfaded r—19.942018-11-102026-09-2948701.00118.6094, -0.9257
ZTF ZTF18acnntgr EclBinfaded r−0.314.792018-11-072026-09-2918261.00120.9798, -2.7740
ZTF ZTF18acnnthq EclBinfaded r−0.319.112017-12-082026-09-2932351.00118.1295, -3.3072
ZTF ZTF18acnntij EclBin18.18 r+0.117.672018-11-072026-09-2953631.00121.8392, -3.7041
ZTF ZTF18acnntik Variable*faded r−0.2—2018-11-072026-09-29881.00121.6413, -3.6093
ZTF ZTF18acnntjk EclBinfaded r−0.218.972018-11-072026-09-2934411.00122.8499, -3.7914
ZTF ZTF18acnntkw EclBinfaded r−0.318.802017-12-082026-09-2946741.00123.4985, -6.1240
ZTF ZTF18acnntnf Unknownfaded r−0.3—2018-11-072026-09-2965991.00122.0416, -5.8473
ZTF ZTF18acnntni BLLacfaded r−0.6—2018-11-072026-09-29781281.00121.7900, -5.6872
ZTF ZTF18acnnvei RRLyraefaded r−0.217.632017-12-082026-09-2970981.00121.7417, -2.9098
ZTF ZTF18acnnvej EclBinfaded r−0.518.812017-12-082026-09-2947591.00121.6772, -3.5020
ZTF ZTF18acnnwxt EclBinfaded r−0.318.972018-11-072026-09-2949571.00118.4286, -0.8903
ZTF ZTF18acpdjwy EclBinfaded r−0.317.622018-11-072026-09-2947601.00118.2471, -0.4134
ZTF ZTF18acpdkbo EclBin18.31 r+0.117.662018-11-072026-09-2944661.00121.1424, -2.7457
ZTF ZTF18acpdkbp Starfaded r−0.2—2018-11-172026-09-2955951.00120.6363, -2.9416
ZTF ZTF18acpdlio Starfaded r−0.2—2018-11-072026-09-2957781.00122.3587, -5.3987
ZTF ZTF18acpdljd RRLyraefaded r−0.317.372018-11-172026-09-2965921.00122.8654, -4.7866
ZTF ZTF18acpdmlt EclBinfaded r−0.918.832018-11-072026-09-2916251.00123.5910, -5.6295
ZTF ZTF18acpdnys EclBinfaded r−0.118.062017-12-082026-09-2928311.00121.5557, -5.3015
ZTF ZTF18acpdoms RRLyraefaded r−0.116.002017-12-082026-09-2959791.00121.1339, -2.5325
ZTF ZTF18acpdomu EclBin18.82 r+0.117.822018-11-072026-09-2970981.00120.7644, -1.7735
ZTF ZTF18acpdona RRLyrae17.25 r+0.316.422017-12-082026-09-2950781.00120.1984, -4.3388
ZTF ZTF18acpdonb EclBin17.16 r+0.116.532018-11-072026-09-2944571.00120.0437, -4.0945