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
2,951–3,000 of 214,524 · All objects seen in the 7 nights
ObjectClassLast magRisePeakFirst seenLast seenNightsDetectionsRel.RA, DecPartner
ZTF ZTF20acjqmdw Unknown15.70 r+0.115.702018-11-212026-09-29110.99120.7873, -0.3763
ZTF ZTF20aclgkcf Unknown18.12 r+0.118.122020-01-022026-09-2917181.00120.7356, -5.0622
ZTF ZTF20acmghar Unknownfaded r−0.2—2020-01-022026-09-299111.00119.1924, -4.4090
ZTF ZTF20acyxbhk Unknown18.54 r+0.218.142018-11-172026-09-2960831.00122.0277, -5.8824
ZTF ZTF20acztcpa Unknown18.33 r+0.118.332020-12-222026-09-29110.17124.2324, -5.6482
ZTF ZTF20adaqcep Unknownfaded r−0.2—2020-02-242026-09-2961931.00122.5398, -5.9847
ZTF ZTF21aabvono Unknown17.58 r+0.217.582018-12-302026-09-2963921.00117.9096, 0.8934
ZTF ZTF21aahbhun Star17.33 r+0.217.332018-12-132026-09-2912141.00118.0949, -3.5628
ZTF ZTF21aakbmiw Unknownfaded r−0.2—2020-01-042026-09-2957881.00121.4648, -4.7531
ZTF ZTF21aalmrvy EclBinfaded r−0.1—2018-11-072026-09-29220.82121.9847, -6.1982
ZTF ZTF21aamorqh Star18.69 r+0.118.692019-04-262026-09-29220.99118.9292, 0.5413
ZTF ZTF21aapdxno Unknownfaded r−0.3—2020-10-132026-09-29721131.00122.2606, -3.9946
ZTF ZTF21acfjeni AGNfaded r−0.219.022018-12-282026-09-2937421.00119.3326, -0.5392
ZTF ZTF21acgvimt Unknownfaded r−0.1—2018-11-212026-09-29660.95122.6386, -4.1683
ZTF ZTF21aclhtmz Unknownfaded r−0.2—2020-12-152026-09-2917171.00119.0445, -4.6580
ZTF ZTF21aclivdw **faded r−0.117.342018-11-102026-09-29991.00119.7830, -5.9313
ZTF ZTF21acskgkt Starfaded r−0.1—2019-10-222026-09-2952761.00118.8263, -5.1215
ZTF ZTF22abkqubd Unknown18.69 r+0.218.462022-10-032026-09-29681031.00120.5332, -0.6231
ZTF ZTF22abpvuvq Unknownfaded r−0.2—2022-04-192026-09-2960861.00121.5531, -4.9331
ZTF ZTF22abqoedx Unknown19.13 r+0.618.772019-10-192026-09-29761171.00117.8990, -1.3462
ZTF ZTF22abxlkwj Unknownfaded r−0.1—2022-10-282026-09-299100.99118.1377, -3.0825
ZTF ZTF23abefemg Unknown18.67 r+0.218.612018-11-162026-09-2922241.00119.2141, 0.4603
ZTF ZTF23abhyuup Unknownfaded r−0.2—2019-03-012026-09-2936461.00118.0513, -3.5268
ZTF ZTF23abnbrrv Star15.12 r+0.115.062018-11-172026-09-29660.97118.9999, 0.7621
ZTF ZTF23abnznpa EclBin16.88 r+0.116.882017-12-082026-09-29551.00118.2804, -0.8346
ZTF ZTF23abnzrrb Unknownfaded r−0.118.622020-01-062026-09-2913131.00124.6556, -2.7449
ZTF ZTF24aacfxrk Unknown18.11 r+0.118.112024-01-152026-09-29220.98118.0741, 0.6200
ZTF ZTF24abmloed Unknownfaded r−0.2—2024-10-122026-09-2956731.00118.5108, -2.0340
ZTF ZTF24abriasf Unknown18.15 r+0.118.152018-11-262026-09-29991.00120.9713, -3.6254
ZTF ZTF24abrxlhj Unknown18.86 r+0.118.862021-01-062026-09-29110.99122.5781, -6.2483
ZTF ZTF25aabxmez Unknownfaded r−0.1—2018-11-212026-09-29110.81124.1941, -4.0391
ZTF ZTF25acgrpyk Starfaded r−0.2—2018-12-042026-09-29441.00117.8447, -5.5287
ZTF ZTF26aahcacj Unknownfaded r−0.1—2018-12-162026-09-29440.57121.4726, -5.6503
ZTF ZTF26abyaoqe Solar System MPC18.61 r—18.612020-12-102026-09-29111.00118.2215, 0.6589
ZTF ZTF26abyaoqt Unknown18.02 r+2.518.022026-09-292026-09-29111.00121.2816, -5.7956
ZTF ZTF26abyaosa Solar System MPC18.62 r—18.622026-09-292026-09-29111.00119.9434, -1.9805
ZTF ZTF17aaagvzg EclBinfaded r−0.214.352017-12-142026-09-2929351.00123.7350, 21.1520
ZTF ZTF17aaagvzo RRLyrae18.88 r+0.318.062017-12-142026-09-2961721.00123.7269, 21.4257
ZTF ZTF17aaaioyb RRLyrae17.81 r+0.317.072017-12-142026-09-2959821.00123.7340, 20.0711
ZTF ZTF17aaaioyd EclBin14.60 r+0.214.412017-12-142026-09-2953671.00121.1721, 21.4056
ZTF ZTF17aaaiozd EclBinfaded r−0.316.172017-12-142026-09-29771171.00122.3483, 19.2851
ZTF ZTF17aaaipcr EclBin16.62 r+0.316.112017-12-142026-09-2951781.00120.9188, 16.4461
ZTF ZTF17aaaipgs EclBin14.81 r+0.214.292017-12-142026-09-2950761.00122.7154, 15.6429
ZTF ZTF17aaaipkk RRLyrae18.38 r+0.417.572017-12-142026-09-2955771.00121.0909, 17.2480
ZTF ZTF17aaaipnk EclBin18.20 r+0.116.962017-12-142026-09-2967931.00124.4823, 16.1138
ZTF ZTF17aaajdbk EclBin16.24 r+0.215.732017-12-142026-09-2944601.00123.5403, 18.4060
ZTF ZTF17aaajdpe EclBinfaded r−0.115.652017-12-142026-09-2951801.00120.8490, 16.5361
ZTF ZTF17aaajdpf EclBin16.96 r+0.216.332017-12-142026-09-2944581.00120.7794, 16.7617
ZTF ZTF17aaakskx RRLyrae18.63 r+0.217.062017-12-152026-09-2967881.00127.0480, 17.9115
ZTF ZTF17aaakuhr CataclyV*16.14 r+0.715.892017-12-142026-09-29871471.00123.2370, 19.1992