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
2,451–2,500 of 214,524 · All objects seen in the 7 nights
ObjectClassLast magRisePeakFirst seenLast seenNightsDetectionsRel.RA, DecPartner
ZTF ZTF18aabjrxj EclBin17.97 r+0.217.522017-12-142026-09-2952851.00122.5566, 3.9173
ZTF ZTF18aabjwwq EclBin18.85 r+0.118.042018-01-112026-09-2957901.00120.3819, 4.9811
ZTF ZTF18aabkfmh EclBin18.89 r+0.117.292017-12-152026-09-2930451.00123.2982, 3.0139
ZTF ZTF18aabnexi Unknown17.14 r+0.216.592018-02-112026-09-29761781.00123.3535, 8.2824
ZTF ZTF18aagfkil Unknown18.34 r+0.318.342018-12-162026-09-2929361.00120.5093, 8.2612
ZTF ZTF18aaqpjth BYDraV*16.75 r+0.216.752018-01-142026-09-29641221.00123.5086, 8.0917
ZTF ZTF18abuqhbk QSO18.90 r+0.517.542018-02-252026-09-29933031.00122.6724, 8.1667
ZTF ZTF18achdjpx Unknown18.68 r+0.118.282018-11-072026-09-2922311.00120.4792, 1.0872
ZTF ZTF18aclrhgj EclBin15.40 r+0.214.932018-01-112026-09-29851701.00120.3378, 0.9756
ZTF ZTF18acnnska EclBinfaded r−0.2—2017-12-152026-09-2925381.00123.7172, 0.8691
ZTF ZTF18acrxmie Unknown17.73 r+0.117.462018-11-082026-09-2912140.99120.4312, 5.3659
ZTF ZTF18acuqulq EclBin18.59 r+0.217.892018-11-072026-09-29731451.00120.4632, 2.9689
ZTF ZTF18acurpmw EclBinfaded r−0.215.932018-01-112026-09-2915171.00126.3143, 4.3776
ZTF ZTF18acurppx EclBinfaded r−0.114.392018-12-092026-09-29681.00121.7281, 5.9019
ZTF ZTF18acurpqj Unknownfaded r−0.116.952018-11-082026-09-2950721.00127.3219, 2.2048
ZTF ZTF18acurpto QSOfaded r−0.619.212018-11-072026-09-2951911.00123.3798, 4.1637
ZTF ZTF18acurpws EclBin18.82 r+0.117.932018-01-132026-09-2946681.00123.3827, 3.4261
ZTF ZTF18acurpwt Unknown18.12 r+0.117.482018-12-092026-09-2941601.00123.6251, 2.8144
ZTF ZTF18acurpwu Unknownfaded r−0.1—2018-04-022026-09-2918181.00123.0152, 2.8534
ZTF ZTF18acurqag EclBinfaded r−0.218.112017-12-142026-09-2938561.00121.5156, 3.9336
ZTF ZTF18acurqak EclBin15.85 r+0.115.382017-12-142026-09-2927331.00121.3420, 1.8827
ZTF ZTF18acurqan AGB*_Candidatefaded r−0.114.802018-11-072026-09-29891.00122.7135, 3.9438
ZTF ZTF18acurqar EclBin18.52 r+0.117.802018-11-172026-09-2932401.00122.4048, 3.6763
ZTF ZTF18acurqas EclBinfaded r−0.618.642018-11-262026-09-29461.00122.2928, 4.3735
ZTF ZTF18acurqav Unknown17.35 r+0.116.822018-11-172026-09-2937421.00125.3572, 2.9841
ZTF ZTF18acurqcs Variable*14.81 r+0.214.582018-04-022026-09-29811371.00126.1864, 3.1938
ZTF ZTF18acurqib EclBin17.92 r+0.116.772018-11-072026-09-2925331.00123.4646, 1.5944
ZTF ZTF18acvvtlc EclBinfaded r−0.116.572018-11-072026-09-2922241.00123.6159, 7.7726
ZTF ZTF18acvvtof EclBin18.74 r+0.217.802018-01-112026-09-2941471.00123.0959, 6.6056
ZTF ZTF18acvvtqp EclBinfaded r−0.218.962018-01-112026-09-2940601.00120.3244, 1.3481
ZTF ZTF18acvvtva RSCVnV*15.99 r+0.215.862018-11-052026-09-2958881.00122.0876, 5.8702
ZTF ZTF18acvvtwj Variable*faded r−0.1—2018-11-082026-09-2928301.00121.1364, 8.0049
ZTF ZTF18acvvtxz EclBinfaded r−0.318.772018-11-072026-09-2933371.00125.8595, 4.0427
ZTF ZTF18acvvucf Unknown17.90 r+0.217.542018-11-082026-09-2964831.00126.9416, 1.4360
ZTF ZTF18acvvunp EclBinfaded r−0.216.722018-01-112026-09-298101.00122.0634, 3.1440
ZTF ZTF18acvvuvt Unknownfaded r−0.2—2018-01-132026-09-2931371.00123.3236, 5.9316
ZTF ZTF18acvvvfn EclBinfaded r−0.117.852017-12-142026-09-2920221.00122.8757, 3.9529
ZTF ZTF18acvwgyl AGNfaded r−0.318.072018-12-132026-09-29811461.00124.5825, 1.8584
ZTF ZTF18acvwhfu Unknown16.81 r+0.216.672018-11-082026-09-29821461.00123.3863, 7.2769
ZTF ZTF18acvwhlm Unknown16.15 r+0.115.912018-11-172026-09-2934391.00125.8268, 4.2795
ZTF ZTF18acvwhmh EclBinfaded r−0.217.612018-11-262026-09-29621111.00123.0056, 3.4247
ZTF ZTF18acvwhoj Unknown18.20 r+0.017.582018-12-132026-09-2915151.00122.9693, 4.7484
ZTF ZTF18acvwhor Unknownfaded r−0.315.702018-12-132026-09-29591101.00121.1488, 2.3630
ZTF ZTF18acvwhrw BLLac18.87 r+0.718.422018-11-072026-09-2923381.00122.8613, 1.7811
ZTF ZTF18acvwhsd EclBinfaded r−0.116.632018-11-072026-09-2911111.00122.4624, 7.3314
ZTF ZTF18acwvtzh Unknownfaded r−0.1—2018-11-052026-09-2940641.00120.2466, 5.3339
ZTF ZTF18acwvuox Star17.62 r+0.117.622018-12-162026-09-29331.00120.4465, 2.8754
ZTF ZTF18acwwlcf RSCVnV*17.56 r+0.217.392018-11-072026-09-2934451.00122.9573, 7.6173
ZTF ZTF18acwwljq Seyfert1AT 2018kwv17.48 r+0.216.932018-11-172026-09-29651291.00123.6058, 4.3424
ZTF ZTF18acwwlli EclBin16.19 r+0.115.542017-12-182026-09-2960801.00122.4447, 6.6596