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
2,401–2,450 of 214,524 · All objects seen in the 7 nights
ObjectClassLast magRisePeakFirst seenLast seenNightsDetectionsRel.RA, DecPartner
ZTF ZTF17aaapjip Unknown17.14 r+0.115.992017-12-142026-09-2967861.00122.8514, 7.7298
ZTF ZTF17aaapjir EclBinfaded r−0.418.202017-12-142026-09-29731001.00121.2904, 4.7340
ZTF ZTF17aaapjny EclBin16.68 r+0.216.462017-12-142026-09-29671361.00120.7309, 8.1552
ZTF ZTF17aabtfkh EclBinfaded r−0.116.402017-12-182026-09-2933431.00121.2621, 3.2778
ZTF ZTF17aabtfnw EclBinfaded r−0.316.472017-12-142026-09-2953651.00122.8285, 6.7818
ZTF ZTF17aabtfpx EclBin17.87 r+0.117.432017-12-152026-09-2955671.00121.8541, 4.9259
ZTF ZTF17aabtfqu EclBin18.67 r+0.117.592017-12-152026-09-29781581.00120.4364, 6.7392
ZTF ZTF17aabtfth EclBin19.08 r+0.118.512017-12-142026-09-2926291.00121.6603, 1.3083
ZTF ZTF17aabwjsx EclBin17.38 r+0.115.132017-12-082026-09-2929431.00120.6394, 1.0629
ZTF ZTF18aaabhhl EclBin17.63 r+0.317.432017-12-142026-09-29861661.00120.2029, 5.5810
ZTF ZTF18aaablrl Unknown16.12 r+0.116.062018-01-112026-09-2913141.00125.3991, 3.8812
ZTF ZTF18aaabndo RRLyrae15.56 r+0.415.192018-01-112026-09-2966881.00125.4640, 3.3986
ZTF ZTF18aaabpcf EclBinfaded r−0.314.762017-12-142026-09-2957731.00123.0125, 5.1576
ZTF ZTF18aaacaie AGB*_Candidate15.19 r+0.114.422018-01-112026-09-2918231.00123.3886, 2.1942
ZTF ZTF18aaacajj RRLyrae17.75 r+0.417.212017-12-142026-09-2964951.00124.5504, 3.8229
ZTF ZTF18aaacani EclBinfaded r−0.316.042018-01-112026-09-29661011.00125.4601, 1.6474
ZTF ZTF18aaaccvg EclBinfaded r−0.117.332017-12-142026-09-2941441.00123.2713, 5.4238
ZTF ZTF18aaaciea EclBinfaded r−0.516.542018-01-112026-09-29741051.00125.3949, 1.9179
ZTF ZTF18aaacolv Unknown15.54 r+0.215.332018-01-112026-09-29821601.00122.7257, 4.8364
ZTF ZTF18aaactin EclBin18.45 r+0.217.692017-12-142026-09-2959801.00123.1718, 6.8907
ZTF ZTF18aaafyff RRLyraefaded r−0.216.282018-01-112026-09-29731241.00125.3173, 2.2948
ZTF ZTF18aaafyzc EclBinfaded r−0.116.322018-01-112026-09-2957711.00123.2005, 5.0717
ZTF ZTF18aaafzqy RRLyraefaded r−0.215.932017-12-142026-09-29731141.00121.8062, 7.7301
ZTF ZTF18aaagayq EclBinfaded r−0.217.042017-12-142026-09-2958681.00121.3766, 7.2636
ZTF ZTF18aaagazc UnknownAT 2023vrp17.69 r+2.416.912018-01-132026-09-296101.00123.2368, 7.9654
ZTF ZTF18aaagbry RRLyrae17.40 r+0.116.542017-12-142026-09-2950771.00122.3502, 4.0543
ZTF ZTF18aaagbsa EclBin17.18 r+0.316.292018-01-132026-09-2943631.00122.8570, 4.3835
ZTF ZTF18aaagpkc RSCVnV*14.82 r+0.113.932018-11-172026-09-2930461.00123.2303, 2.9125
ZTF ZTF18aaahrhm Starfaded r−0.118.042018-01-132026-09-29661.00121.6881, 3.9547
ZTF ZTF18aaambjq RRLyraefaded r−0.315.762017-12-142026-09-29761201.00124.5903, 4.3850
ZTF ZTF18aaasixy EclBin18.70 r+0.217.952017-12-142026-09-29641201.00121.5331, 8.2611
ZTF ZTF18aabipvu EclBin15.30 r+0.114.952017-12-152026-09-2938540.98123.0624, 2.1596
ZTF ZTF18aabipvw EclBinfaded r−0.419.622017-12-182026-09-2918201.00123.1382, 2.3465
ZTF ZTF18aabiqno EclBinfaded r−0.115.472017-12-182026-09-29892041.00120.4658, 5.1153
ZTF ZTF18aabirkf RRLyrae15.26 r+0.314.232017-12-142026-09-2943581.00123.0546, 4.8806
ZTF ZTF18aabisgb EclBinfaded r−0.115.192017-12-142026-09-2938551.00123.4527, 4.4437
ZTF ZTF18aabithx EclBin16.78 r+0.115.782018-01-132026-09-2963891.00121.2482, 5.9501
ZTF ZTF18aabiuej Unknownfaded r−0.116.842018-01-132026-09-2923271.00124.1579, 2.7690
ZTF ZTF18aabiwyi EclBin17.05 r+0.116.542017-12-142026-09-2925291.00121.3742, 0.8846
ZTF ZTF18aabiwyl Unknownfaded r−0.313.732018-01-132026-09-29601091.00121.8864, 1.1088
ZTF ZTF18aabjabq EclBin16.31 r+0.116.082017-12-142026-09-2945611.00127.0426, 2.0409
ZTF ZTF18aabjepr Unknown17.23 r+0.115.822018-01-132026-09-2963781.00126.2539, 3.1109
ZTF ZTF18aabjijt Unknown18.83 r+0.118.322018-01-132026-09-2947751.00123.0499, 1.4053
ZTF ZTF18aabjkwn EclBinfaded r−0.314.912018-01-112026-09-2913161.00120.3277, 3.6095
ZTF ZTF18aabjnvo EclBin_Candidate17.19 r+0.117.132018-01-112026-09-2954661.00124.1962, 2.4517
ZTF ZTF18aabjoph EclBinfaded r−0.418.092018-01-132026-09-2930421.00125.5782, 3.1793
ZTF ZTF18aabjoxz EclBin14.72 r+0.214.442018-01-132026-09-2958851.00126.8417, 2.8574
ZTF ZTF18aabjphb QSOfaded r−0.118.082018-01-112026-09-29601161.00123.2461, 1.2009
ZTF ZTF18aabjpho Star18.08 r+0.118.082018-01-112026-09-29110.86122.9583, 0.9773
ZTF ZTF18aabjply EclBinfaded r−0.116.532018-01-132026-09-2933371.00121.1053, 7.1458