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
2,251–2,300 of 214,523 · All objects seen in the 7 nights
ObjectClassLast magRisePeakFirst seenLast seenNightsDetectionsRel.RA, DecPartner
ZTF ZTF18aafbpvc QSO19.48 r+0.319.002018-11-182026-09-29701211.00126.1460, 27.7728
ZTF ZTF18aafbufb Unknown18.49 r+0.217.952019-01-292026-09-2947641.00124.6738, 26.9984
ZTF ZTF18aafbvjr Seyfert1AT 2019vkt19.37 r+0.218.742018-02-252026-09-2959951.00125.2469, 26.7560
ZTF ZTF18aafbwha RRLyrae19.72 r+0.219.432017-12-082026-09-2914151.00126.8919, 24.5873
ZTF ZTF18aafbxrm QSOfaded r−0.619.812021-02-052026-09-29741651.00124.7068, 26.5834
ZTF ZTF18aafcgfl Unknown16.64 r+0.116.462018-11-052026-09-29460.99125.6323, 24.6961
ZTF ZTF18aafcgwy Unknown18.79 r+0.117.662019-04-292026-09-29881.00125.7329, 24.3445
ZTF ZTF18aafcivh Unknown19.05 r+0.319.052020-01-272026-09-29111.00126.0973, 24.7304
ZTF ZTF18aafcqxh QSO18.15 r+0.518.042018-11-122026-09-2928311.00131.9452, 23.1542
ZTF ZTF18aafdkdl RSCVnV*14.40 r+0.214.402018-04-092026-09-2914150.99125.6478, 28.9220
ZTF ZTF18aafdylj Unknownfaded r−0.219.092018-12-032026-09-2910141.00125.3477, 25.3936
ZTF ZTF18aafebbb QSO17.77 r+0.517.542018-09-142026-09-29641251.00125.1891, 24.5314
ZTF ZTF18aafebrq QSOfaded r−0.419.432020-02-152026-09-2949831.00125.3412, 25.1381
ZTF ZTF18aafeetj Unknown19.14 r+0.119.142018-04-192026-09-29110.97130.4600, 25.7793
ZTF ZTF18aafepxw Unknown18.28 r+0.218.012018-12-032026-09-2923241.00130.3995, 23.0618
ZTF ZTF18aaffbbf Unknown19.22 r+0.219.222018-12-032026-09-29110.99128.8072, 23.1993
ZTF ZTF18aaffotk QSO19.05 r+0.318.892019-05-062026-09-2957711.00129.6095, 25.5031
ZTF ZTF18aaffpyq QSO19.25 r+0.318.762019-01-262026-09-29771221.00129.3534, 25.2558
ZTF ZTF18aaffvje QSO18.01 r+0.217.192018-11-142026-09-29681141.00128.8993, 24.9945
ZTF ZTF18aaffzbz Blazar18.70 r+0.418.172019-11-042026-09-2963841.00129.4177, 24.9065
ZTF ZTF18aagqcqd Unknownfaded r−0.519.362018-03-132026-09-2946531.00126.7476, 25.9852
ZTF ZTF18aagqddc Unknownfaded r−0.3—2018-03-132026-09-29881.00125.3200, 26.6198
ZTF ZTF18aahetll EclBinfaded r−0.217.252018-04-062026-09-29731261.00132.0228, 25.5826
ZTF ZTF18aahrdem EclBin18.22 r+0.117.662017-11-192026-09-2912121.00126.6105, 29.8671
ZTF ZTF18aawxaps Unknownfaded r−0.117.782018-11-142026-09-2923271.00128.8778, 22.7559
ZTF ZTF18aawxbkk Unknownfaded r−0.2—2019-04-112026-09-2919201.00129.4186, 23.0735
ZTF ZTF18abvgiru Unknownfaded r−0.115.702018-01-142026-09-29831461.00125.0039, 24.5299
ZTF ZTF18abwcizo Unknown15.89 r+0.115.722017-12-172026-09-2950590.99130.0442, 24.8941
ZTF ZTF18abwcjbg Star15.49 r+0.115.162018-09-142026-09-2932331.00128.4698, 27.2800
ZTF ZTF18abxbmks BLLac18.19 r+0.818.112018-05-252026-09-29691191.00125.2134, 23.8959
ZTF ZTF18accdvng AGNAT 2018xw19.17 r+0.619.172018-11-022026-09-2929381.00130.2106, 24.4784
ZTF ZTF18acdvseq EclBinfaded r−0.219.122017-12-152026-09-29661.00126.5392, 23.7306
ZTF ZTF18aclldts Unknownfaded r−0.218.192017-11-192026-09-2956711.00126.6323, 29.7031
ZTF ZTF18acmsdot Starfaded r−0.215.942018-11-202026-09-2961801.00128.3022, 25.6956
ZTF ZTF18acpbbtv UnknownAT 2018dlpfaded r−1.219.072017-12-142026-09-2944551.00126.0158, 24.5518
ZTF ZTF18acsvddp Variable*faded r−0.117.602018-12-032026-09-2956651.00131.1291, 22.9900
ZTF ZTF18adaylkh EclBin15.63 r+0.215.332018-02-092026-09-2942501.00128.0408, 28.9955
ZTF ZTF18adijixn Unknownfaded r−0.2—2018-11-172026-09-29331.00131.5739, 23.9158
ZTF ZTF18adobyue Seyfert1faded r−0.419.402018-09-292026-09-2923261.00128.1954, 28.8866
ZTF ZTF19aaedidj EclBinfaded r−0.216.892017-12-152026-09-2947681.00126.3079, 24.7105
ZTF ZTF19aalcwec Seyfert119.28 r+0.619.282018-05-252026-09-2914151.00127.3776, 27.4730
ZTF ZTF19ackjrje QSOfaded r−0.318.912019-05-062026-09-2961871.00128.8861, 25.4410
ZTF ZTF19acmbqga Unknown18.29 r+0.118.292019-11-012026-09-29110.04124.6317, 28.7552
ZTF ZTF19acrshwj Unknownfaded r−0.218.772019-01-302026-09-2956821.00124.6916, 28.2925
ZTF ZTF19adcblot blue19.01 r+1.118.722019-12-292026-09-29881631.00129.9391, 23.8434
ZTF ZTF20aaaxlzc Unknownfaded r−0.1—2017-12-172026-09-29221.00127.2384, 24.6153
ZTF ZTF20aalvngz Seyfert217.95 r+0.117.952018-11-142026-09-29331.00129.5457, 24.8953
ZTF ZTF20aarxekg EclBinfaded r−0.1—2017-11-192026-09-2939451.00126.2611, 29.6917
ZTF ZTF20actyyfp Unknown15.10 r+0.215.102018-11-122026-09-2917180.73126.9388, 27.8399
ZTF ZTF20acxhxul Unknownfaded r−0.118.972019-11-252026-09-2934381.00126.7092, 25.4031