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
3,001–3,050 of 214,524 · All objects seen in the 7 nights
ObjectClassLast magRisePeakFirst seenLast seenNightsDetectionsRel.RA, DecPartner
ZTF ZTF17aaansrc EclBin18.79 r+0.218.212017-12-142026-09-2956721.00125.3806, 15.7757
ZTF ZTF17aaaokag EclBinfaded r−0.517.082017-12-032026-09-29671271.00120.6724, 19.4362
ZTF ZTF17aaaolib EclBinfaded r−0.117.392018-02-072026-09-2953641.00127.0241, 15.9400
ZTF ZTF17aaaoyly RRLyrae19.08 r+0.218.322017-12-142026-09-2955701.00126.7085, 15.2293
ZTF ZTF17aaapmlh RRLyraefaded r−0.313.932017-12-152026-09-2952721.00124.1498, 18.3495
ZTF ZTF17aaapmoz RRLyraefaded r−0.414.652017-12-142026-09-2953801.00122.2958, 18.4924
ZTF ZTF17aabhbxo EclBinfaded r−0.517.822017-12-142026-09-2959821.00126.7435, 16.3922
ZTF ZTF17aabofis EclBin15.71 r+0.215.362017-12-152026-09-2944611.00120.4895, 21.6912
ZTF ZTF17aabqmuf RRLyraefaded r−0.116.982017-12-142026-09-29691011.00123.4119, 19.7922
ZTF ZTF17aabtbqy RRLyrae17.05 r+0.416.702017-12-142026-09-2939651.00122.9704, 15.9776
ZTF ZTF17aabtggx EclBin17.62 r+0.116.822017-12-142026-09-2956991.00124.7863, 15.3118
ZTF ZTF18aaabins C*faded r−0.513.502018-01-112026-09-2956701.00127.3129, 18.3854
ZTF ZTF18aaabjkh AGB*faded r−0.513.952018-01-112026-09-2968891.00126.7088, 16.3822
ZTF ZTF18aaabjpm EclBinfaded r−0.215.492018-01-112026-09-2920241.00123.2999, 19.8896
ZTF ZTF18aaabvea EclBinfaded r−0.217.842017-12-052026-09-2944571.00120.0637, 21.7194
ZTF ZTF18aaabxhy RRLyrae17.37 r+0.216.832018-01-112026-09-2944621.00120.9956, 15.8132
ZTF ZTF18aaacbcp RRLyraefaded r−0.216.192018-01-112026-09-29671001.00124.9045, 15.7985
ZTF ZTF18aaadavy EclBin17.53 r+0.116.772017-12-152026-09-2941511.00121.1364, 17.3357
ZTF ZTF18aaahmka Unknown17.03 r+0.117.032018-11-062026-09-29220.95122.5332, 17.9137
ZTF ZTF18aaahobh EclBinfaded r−0.216.872017-12-142026-09-2924251.00122.0588, 18.8260
ZTF ZTF18aaahoir RRLyrae18.51 r+0.218.222017-12-142026-09-2956691.00122.3655, 19.2087
ZTF ZTF18aaainqo RRLyraefaded r−0.315.672017-12-142026-09-2951631.00121.1128, 20.1306
ZTF ZTF18aaaiylq EclBin15.84 r+0.115.592018-01-132026-09-2916220.99125.3935, 17.5528
ZTF ZTF18aaajbjj Unknown18.89 r+0.118.672017-12-052026-09-2925271.00120.4957, 19.8917
ZTF ZTF18aaasgvf Variable*18.07 r+0.117.772018-01-112026-09-2934451.00125.6004, 15.3213
ZTF ZTF18aaaspfl EclBin19.18 r+0.218.372017-12-142026-09-2955651.00122.7385, 19.7633
ZTF ZTF18aaaxedl Starfaded r−0.1—2018-02-092026-09-29440.97123.4923, 20.1756
ZTF ZTF18aaaxeqf RRLyrae18.49 r+0.418.292017-12-182026-09-2920231.00122.3509, 19.9140
ZTF ZTF18aaaxgar EclBinfaded r−0.618.342017-12-152026-09-2916181.00121.1995, 19.4711
ZTF ZTF18aaayvhl EclBinfaded r−0.4—2017-12-142026-09-2914161.00123.2442, 21.2467
ZTF ZTF18aaaywov EclBin19.25 r+0.419.202017-12-182026-09-2927301.00124.7993, 18.3729
ZTF ZTF18aaayxzo EclBin19.12 r+0.118.792017-12-142026-09-2924271.00120.8987, 17.2098
ZTF ZTF18aaayyyy EclBinfaded r−0.418.722017-12-142026-09-2921221.00124.5585, 16.1701
ZTF ZTF18aabjzbg Unknownfaded r−0.2—2018-01-132026-09-29331.00121.8167, 15.9997
ZTF ZTF18aabjzjq EclBinfaded r−0.215.532018-01-132026-09-298121.00121.1913, 16.5726
ZTF ZTF18aabnmse EclBinfaded r−0.217.572017-12-142026-09-2917191.00123.3969, 21.9311
ZTF ZTF18aabsmml RSCVnV*faded r−0.717.442018-03-052026-09-2955861.00123.4723, 21.5388
ZTF ZTF18aabvpbz EclBinfaded r−0.218.882017-12-142026-09-2920231.00121.1610, 16.3140
ZTF ZTF18aabvqoj EclBinfaded r−0.118.032017-12-142026-09-2924281.00123.3126, 21.0702
ZTF ZTF18aaeviad QSO18.26 r+0.217.642017-12-202026-09-2950661.00120.3028, 19.2625
ZTF ZTF18aaewjjw ChemPec*15.21 r+0.214.462017-12-052026-09-29761621.00120.6102, 21.8336
ZTF ZTF18aafsybe Unknown17.05 r+0.116.182018-11-142026-09-29220.97125.7491, 16.3208
ZTF ZTF18aafumxr Seyfert1faded r−0.718.352018-03-132026-09-29881721.00125.6161, 15.7918
ZTF ZTF18aafuusp QSO18.91 r+0.318.762019-03-252026-09-29741111.00126.6861, 16.5970
ZTF ZTF18aafwolm QSO18.90 r+0.418.432018-11-082026-09-29831491.00125.9880, 18.2510
ZTF ZTF18aafyabn EclBin18.47 r+0.218.202017-12-152026-09-2922291.00126.2262, 17.9717
ZTF ZTF18aafybuj Unknownfaded r−0.217.542018-02-262026-09-2932421.00127.3992, 17.1542
ZTF ZTF18aafyuiy QSOfaded r−0.3—2022-10-312026-09-2926341.00124.5655, 16.7064
ZTF ZTF18aafyvbf AGNfaded r−0.719.272018-09-142026-09-2962761.00126.6549, 15.4508
ZTF ZTF18aafywyv Star18.46 r+0.117.842018-11-032026-09-2913151.00123.8178, 16.8579