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
2,751–2,800 of 214,524 · All objects seen in the 7 nights
ObjectClassLast magRisePeakFirst seenLast seenNightsDetectionsRel.RA, DecPartner
ZTF ZTF18acqxpka EclBin17.15 r+0.116.282018-11-102026-09-2924281.00120.5095, -5.7126
ZTF ZTF18acqxpkd EclBinfaded r−0.116.742018-11-072026-09-2918231.00120.9464, -5.7321
ZTF ZTF18acqxpkf EclBinfaded r−0.317.902018-11-072026-09-2941591.00121.1408, -5.6240
ZTF ZTF18acqxpkj EclBinfaded r−0.218.432017-12-082026-09-29771.00120.5323, -5.8160
ZTF ZTF18acqxpmm Unknown14.86 r+0.214.862018-11-172026-09-2915180.98119.6689, -5.3204
ZTF ZTF18acqxpnu Unknown16.21 r+0.116.102018-11-172026-09-2930521.00121.0172, -6.1780
ZTF ZTF18acqxpok EclBinfaded r−0.2—2017-12-082026-09-29881.00118.3553, 0.1936
ZTF ZTF18acqxppd RSCVnV*16.43 r+0.115.672018-11-072026-09-29441.00119.7728, -5.6956
ZTF ZTF18acqykxt EclBinfaded r−0.218.742018-11-072026-09-2931381.00121.1058, -5.8826
ZTF ZTF18acqylew EclBinfaded r−0.118.052018-11-172026-09-2929361.00119.7239, -2.8545
ZTF ZTF18acrdhqf Unknownfaded r−0.116.922018-11-172026-09-2932411.00117.9230, -1.6115
ZTF ZTF18acrdhqg Unknown17.70 r+0.117.052018-11-132026-09-2928301.00118.1635, -1.5208
ZTF ZTF18acrdhsw EclBinfaded r−0.119.522018-11-072026-09-2928311.00121.6738, -3.2004
ZTF ZTF18acrdhtt EclBin18.79 r+0.218.792018-11-072026-09-2935401.00120.7173, -1.1653
ZTF ZTF18acrdhun Unknown17.95 r+0.317.832018-11-252026-09-2953901.00120.0525, -2.8176
ZTF ZTF18acrdiag EclBin15.27 r+0.215.042018-11-102026-09-2960881.00124.3541, -5.4071
ZTF ZTF18acrdiai EclBinfaded r−0.316.462018-11-102026-09-2968961.00124.3864, -4.9114
ZTF ZTF18acrdial EclBinfaded r−0.319.092018-11-182026-09-2927281.00124.1825, -4.8653
ZTF ZTF18acrdimh EclBinfaded r−0.116.792018-11-172026-09-2932361.00124.2722, -5.9864
ZTF ZTF18acrdoas Unknownfaded r−0.2—2018-11-252026-09-29701081.00123.6366, -5.8206
ZTF ZTF18acrdobf Unknown17.86 r+0.117.862018-11-182026-09-2923291.00122.3820, -6.2350
ZTF ZTF18acrdobh Unknown16.95 r+0.116.382018-11-252026-09-2941591.00121.1001, -4.9841
ZTF ZTF18acrdocg Unknown16.96 r+0.116.392018-11-252026-09-2937521.00120.2945, -3.5327
ZTF ZTF18acrdocu EclBinfaded r−0.314.492017-12-082026-09-2944561.00118.3812, -1.5503
ZTF ZTF18acrgvcv EclBin17.58 r+0.117.582018-11-252026-09-29671.00122.4599, -6.0730
ZTF ZTF18acrgvgl EclBinfaded r−0.515.932017-12-082026-09-2958721.00118.9483, -1.3659
ZTF ZTF18acrgvls EclBin16.33 r+0.115.532017-12-082026-09-29651181.00117.8224, -2.1703
ZTF ZTF18acrgwdw EclBin15.39 r+0.214.952018-01-112026-09-2915151.00120.3378, 0.9756
ZTF ZTF18acrgwfz EclBin16.20 r+0.115.882017-12-082026-09-2919201.00118.5249, 0.1783
ZTF ZTF18acrgwgh EclBin_Candidate17.80 r+0.117.412018-11-072026-09-29331.00121.0233, -2.9294
ZTF ZTF18acrknmx Star17.77 r+0.117.452018-11-072026-09-2916191.00120.9535, -4.2562
ZTF ZTF18acrmcnv Unknown16.63 r+0.116.082018-11-172026-09-2948651.00120.0488, -6.0794
ZTF ZTF18acrvekb EclBinfaded r−0.217.452018-11-172026-09-2938641.00117.8872, -4.1093
ZTF ZTF18acrxlzr Variable*faded r−0.216.152018-11-172026-09-29922411.00118.5349, 0.9836
ZTF ZTF18acrxnfq Unknown14.57 r+0.213.772017-12-082026-09-299101.00119.2973, -2.5221
ZTF ZTF18acrxnfu RSCVnV*17.05 r+0.216.552017-12-082026-09-29791281.00118.7798, -2.2226
ZTF ZTF18acrxnir Unknownfaded r−0.317.522018-11-212026-09-29821361.00120.6050, -1.1359
ZTF ZTF18acrxnkt EclBin17.61 r+0.117.482018-11-072026-09-2926291.00119.9429, -1.9537
ZTF ZTF18acrxnkv RRLyrae18.50 r+0.117.912018-11-072026-09-2944541.00120.1370, -2.2126
ZTF ZTF18acrxnnk LongPeriodV*faded r−0.3—2018-11-172026-09-2923341.00118.0884, -5.6345
ZTF ZTF18acrxnnm Star16.24 r+0.116.242018-11-072026-09-29891.00118.1044, -6.2392
ZTF ZTF18acrxnnn Variable*16.80 r+0.116.022018-11-282026-09-2944981.00118.2688, -6.1452
ZTF ZTF18acrxnnp EclBinfaded r−0.118.422018-11-262026-09-2910101.00118.5380, -5.8682
ZTF ZTF18acrxntx Unknown18.48 r+0.217.692017-12-082026-09-2946661.00119.3766, -6.2058
ZTF ZTF18acrxnub EclBinfaded r−0.4—2018-11-072026-09-2913161.00119.0786, -6.0320
ZTF ZTF18acrxnvc EclBinfaded r−0.118.602018-11-272026-09-2915161.00119.0239, -4.8415
ZTF ZTF18acrxnww EclBin17.29 r+0.116.932018-11-072026-09-2952811.00118.9930, -3.9641
ZTF ZTF18acrxnwx EclBinfaded r−0.216.912017-12-082026-09-2930371.00119.1360, -4.2413
ZTF ZTF18acrxnwy RSCVnV*faded r−0.1—2018-11-172026-09-2925311.00119.2726, -3.8327
ZTF ZTF18acrxnze CataclyV*faded r−0.813.602017-12-082026-09-2949801.00119.0013, -2.8544