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
2,851–2,900 of 214,524 · All objects seen in the 7 nights
ObjectClassLast magRisePeakFirst seenLast seenNightsDetectionsRel.RA, DecPartner
ZTF ZTF18adpfbcq EclBinfaded r−0.218.852018-11-072026-09-2932371.00122.3145, -4.3608
ZTF ZTF18adplxpi Unknownfaded r−0.1—2018-11-202026-09-29451.00124.2065, -4.2169
ZTF ZTF18adpmdbf EclBinfaded r−0.1—2018-11-172026-09-29550.97121.4497, -2.7900
ZTF ZTF19aaaoimr Unknown17.73 r+0.117.472018-11-272026-09-2934411.00123.3468, -5.2210
ZTF ZTF19aaaoipj EclBinfaded r−0.8—2019-01-042026-09-299101.00120.1772, -2.3820
ZTF ZTF19aabvzfx Unknownfaded r−0.1—2018-12-202026-09-2915161.00118.8578, 0.5579
ZTF ZTF19aabvzok Unknown18.43 r+0.118.342019-01-082026-09-2942491.00118.6436, 0.4537
ZTF ZTF19aabwarx Unknownfaded r−0.1—2018-11-132026-09-29881.00123.3779, -3.8046
ZTF ZTF19aabwjqd Unknown17.69 r+0.117.692019-01-082026-09-29221.00119.4161, -6.2535
ZTF ZTF19aabwlta EclBinfaded r−0.1—2018-11-282026-09-29781.00118.8002, -4.8289
ZTF ZTF19aabwqeh Star17.97 r+0.017.972019-01-082026-09-29110.93120.7059, -5.7859
ZTF ZTF19aabxfmc Unknownfaded r−0.1—2018-11-192026-09-2930341.00122.9986, -5.6220
ZTF ZTF19aabxsym Unknownfaded r−0.0—2019-01-082026-09-29110.14118.1440, -6.3683
ZTF ZTF19aadlzlg Unknownfaded r−0.1—2019-01-122026-09-2949631.00120.7625, -1.1243
ZTF ZTF19aadmaiz Unknownfaded r−0.118.762019-01-122026-09-2943541.00120.1558, -0.2902
ZTF ZTF19aadmamt Unknownfaded r−0.1—2019-01-122026-09-29110.84121.7415, -5.8141
ZTF ZTF19aadmasg Unknown16.72 r+0.316.692019-01-122026-09-2928451.00118.3957, -5.9266
ZTF ZTF19aadqasv EclBinfaded r−0.2—2017-12-082026-09-29231.00120.1052, -5.2493
ZTF ZTF19aadqpec Unknown17.94 r+0.117.942018-11-252026-09-29570.99117.9442, -3.4752
ZTF ZTF19aaljjjd Variable*17.06 r+0.117.062019-01-262026-09-2925291.00120.1591, -1.5839
ZTF ZTF19aaljrwp Unknownfaded r−0.1—2018-11-252026-09-2929331.00120.7991, -2.5102
ZTF ZTF19aamgcox Unknownfaded r−0.1—2018-11-172026-09-29110.70121.8511, -5.6174
ZTF ZTF19aamgcpp Unknownfaded r−0.317.002019-03-142026-09-29771291.00118.3865, -1.0804
ZTF ZTF19aamgqsr AGNfaded r−0.319.062019-01-122026-09-29771831.00119.8621, 1.0717
ZTF ZTF19aamgqst Unknown18.31 r+0.117.672018-11-262026-09-29751161.00120.3116, 0.4362
ZTF ZTF19aamgqtd Starfaded r−0.1—2018-12-292026-09-2911111.00118.6157, -5.5738
ZTF ZTF19aamgquh Unknownfaded r−0.1—2019-03-142026-09-2921301.00118.9203, 0.6606
ZTF ZTF19aaneijz Unknownfaded r−0.219.362019-01-042026-09-2962921.00119.8988, -2.1151
ZTF ZTF19aaneiqe Starfaded r−0.3—2019-03-252026-09-299101.00123.9717, -4.4225
ZTF ZTF19aanejaq QSOAT 2021hik18.98 r+0.318.082019-03-012026-09-29791331.00118.4052, 0.7384
ZTF ZTF19aanqukl Unknownfaded r−0.1—2018-12-162026-09-29341.00118.3741, -5.8126
ZTF ZTF19aapbmdl RRLyrae16.04 r+0.415.022018-11-072026-09-2924261.00119.1121, -1.2213
ZTF ZTF19aarijmn Starfaded r−0.1—2019-04-232026-09-2932411.00119.9802, -6.0665
ZTF ZTF19aarzgsm Variable*18.72 r+0.218.572018-12-292026-09-2954791.00119.9519, 0.6585
ZTF ZTF19aarzgsx Starfaded r−0.1—2019-04-262026-09-2961871.00123.0227, -3.6705
ZTF ZTF19aasadvp Star17.38 r+0.117.382018-11-192026-09-2936391.00120.5452, -0.1415
ZTF ZTF19aatwjwr Unknownfaded r−0.117.952019-05-052026-09-2956841.00120.1780, -1.3265
ZTF ZTF19aatwjyr Unknown18.84 r+0.118.842018-11-172026-09-29671.00119.7479, 0.0959
ZTF ZTF19aatwlmm Starfaded r−0.2—2019-05-052026-09-2950681.00119.3182, -4.4066
ZTF ZTF19acaqpli Unknownfaded r−0.2—2019-09-232026-09-2935491.00118.4408, -5.0403
ZTF ZTF19acbvtrn Unknownfaded r−0.1—2019-10-012026-09-29220.82121.4382, -6.0253
ZTF ZTF19accsleg EclBin17.86 r+0.217.862017-12-082026-09-2923251.00123.0569, -4.4478
ZTF ZTF19accslrj Unknown18.70 r+0.118.202019-10-042026-09-2945691.00118.6702, -5.2053
ZTF ZTF19accsluw Unknownfaded r−0.2—2018-11-072026-09-2950791.00121.0733, -4.0799
ZTF ZTF19accstmz Unknownfaded r−0.1—2018-12-302026-09-2961881.00118.3603, 0.9910
ZTF ZTF19accstqh Unknownfaded r−0.1—2019-10-042026-09-2915201.00119.0169, -4.4006
ZTF ZTF19acdtxrj Unknown16.54 r+0.116.082019-10-082026-09-2926321.00119.8310, -3.3565
ZTF ZTF19acdtyyg Unknownfaded r−0.1—2018-11-192026-09-2938721.00121.2066, 1.0371
ZTF ZTF19acgdlul Unknown18.56 r+0.118.122019-10-012026-09-2920241.00121.0955, -6.2313
ZTF ZTF19acgebjs Unknown18.50 r+0.218.302019-04-262026-09-2963951.00122.1394, -5.2184