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
2,701–2,750 of 214,524 · All objects seen in the 7 nights
ObjectClassLast magRisePeakFirst seenLast seenNightsDetectionsRel.RA, DecPartner
ZTF ZTF18acpdonf EclBinfaded r−0.2—2017-12-082026-09-2946531.00120.2747, -4.3281
ZTF ZTF18acpdonj EclBin18.33 r+0.117.592017-12-082026-09-2966881.00121.0067, -1.0555
ZTF ZTF18acpdonk EclBin17.77 r+0.117.032018-11-072026-09-2911131.00120.7844, -1.0332
ZTF ZTF18acpdonn Unknownfaded r−0.1—2018-11-172026-09-29441.00121.1308, -0.9340
ZTF ZTF18acpdono Starfaded r−0.1—2018-11-172026-09-2964841.00120.8454, -1.4390
ZTF ZTF18acpdonp EclBinfaded r−0.118.512018-11-072026-09-2938491.00121.0038, -1.2483
ZTF ZTF18acpdoos EclBinfaded r−0.617.122018-11-072026-09-2933421.00118.0064, -5.0085
ZTF ZTF18acpdplc Unknownfaded r−0.3—2018-11-252026-09-29771281.00123.1440, -6.1035
ZTF ZTF18acpoelq Unknown18.51 r+0.118.292018-11-102026-09-2918211.00121.5101, -5.2329
ZTF ZTF18acpoepw Unknown18.69 r+0.118.182018-11-172026-09-2940591.00122.7177, -6.0745
ZTF ZTF18acpozyl EclBinfaded r−0.319.372018-11-072026-09-2936371.00118.6393, 0.8066
ZTF ZTF18acppacf EclBinfaded r−0.219.392018-11-072026-09-2931331.00118.2136, 0.2137
ZTF ZTF18acppach EclBinfaded r−0.418.942018-11-072026-09-2926271.00118.5300, -0.4691
ZTF ZTF18acppbqp EclBin17.29 r+0.217.262018-11-072026-09-2932401.00118.0041, -3.4688
ZTF ZTF18acpupkq EclBinfaded r−0.217.012017-12-082026-09-2948561.00120.4596, -0.9239
ZTF ZTF18acpuplg RRLyraefaded r−0.313.552018-11-072026-09-2952691.00124.5805, -3.6570
ZTF ZTF18acpuplv EclBin16.69 r+0.115.962018-11-072026-09-29670.97120.0197, -5.2356
ZTF ZTF18acpuplz Unknown17.66 r+0.116.982018-11-072026-09-2941501.00120.0421, -5.0213
ZTF ZTF18acpupmw RRLyraefaded r−0.215.832017-12-082026-09-2951791.00120.5367, -4.7489
ZTF ZTF18acpupmy EclBinfaded r−0.1—2018-11-072026-09-298101.00120.4482, -4.8990
ZTF ZTF18acpupnn EclBinfaded r−0.218.652018-11-072026-09-2942521.00124.2670, -3.1166
ZTF ZTF18acpupuq EclBin17.85 r+0.117.332018-11-072026-09-2963851.00120.6956, -2.2678
ZTF ZTF18acpwljw Star18.04 r+0.117.812018-11-192026-09-29761141.00121.0303, -2.0479
ZTF ZTF18acpwlkb EclBinfaded r−0.7—2017-12-082026-09-2910101.00118.1998, -5.0197
ZTF ZTF18acpwlkn EclBinfaded r−0.518.112017-12-082026-09-2960771.00120.5787, -0.9774
ZTF ZTF18acpwlqg AGB*_Candidate15.90 r+0.115.902018-11-172026-09-2919201.00119.7644, -4.0766
ZTF ZTF18acpwlqi EclBin18.07 r+0.217.962017-12-082026-09-2931371.00119.6686, -4.0285
ZTF ZTF18acpwlql EclBin19.13 r+0.218.852018-11-102026-09-2929321.00120.3629, -3.7881
ZTF ZTF18acqezcc LongPeriodV*_Candidatefaded r−0.215.682018-11-072026-09-2912131.00120.0444, -1.3113
ZTF ZTF18acqktdk EclBinfaded r−0.1—2018-11-202026-09-29110.94121.0760, 0.0768
ZTF ZTF18acqkuca Unknownfaded r−0.2—2018-11-192026-09-29761201.00120.6659, -1.1181
ZTF ZTF18acqlhwr Variable*18.21 r+0.118.072018-11-202026-09-2912131.00118.4696, -5.3896
ZTF ZTF18acqlioh EclBinfaded r−0.217.662017-12-082026-09-2912141.00120.4428, -2.8029
ZTF ZTF18acqqrqo Star18.45 r+0.118.452018-11-202026-09-29991.00121.2063, -1.8123
ZTF ZTF18acqqrwu EclBinfaded r−0.218.162018-11-072026-09-2942571.00119.9168, -3.3623
ZTF ZTF18acqqtmw EclBinfaded r−0.6—2018-11-042026-09-29781.00117.7274, 0.3388
ZTF ZTF18acqxoza EclBinfaded r−0.214.952017-12-082026-09-29701391.00117.7793, -2.2024
ZTF ZTF18acqxozc EclBin16.96 r+0.116.242017-12-082026-09-29681271.00117.8765, -2.0333
ZTF ZTF18acqxpdb EclBin17.85 r+0.117.852018-11-102026-09-2932381.00124.4490, -4.8487
ZTF ZTF18acqxpfw EclBinfaded r−0.217.062018-11-072026-09-2940631.00121.2308, -4.1212
ZTF ZTF18acqxpfx RRLyraefaded r−0.218.052017-12-082026-09-2942531.00120.8471, -3.7888
ZTF ZTF18acqxpgz LongPeriodV*faded r−0.313.982018-11-072026-09-2943591.00121.0775, -3.6154
ZTF ZTF18acqxpha Unknown18.40 r+1.517.652017-12-082026-09-2937491.00120.9682, -3.9904
ZTF ZTF18acqxphc EclBinfaded r−0.218.312018-11-072026-09-2948521.00120.1978, -0.9001
ZTF ZTF18acqxphm EclBin16.84 r+0.116.482018-11-072026-09-2921221.00119.9021, -4.8613
ZTF ZTF18acqxphx EclBin15.09 r+0.214.692018-11-072026-09-2958841.00120.4634, -0.5572
ZTF ZTF18acqxpid CataclyV*faded r−0.615.402018-11-072026-09-29721151.00120.6432, -0.1611
ZTF ZTF18acqxpje Mira14.95 r+0.512.312018-11-072026-09-2951771.00119.8744, -6.1860
ZTF ZTF18acqxpji EclBinfaded r−0.418.252018-11-072026-09-2935441.00120.0116, -5.9491
ZTF ZTF18acqxpjz Unknown15.00 r+0.214.662018-11-102026-09-2927321.00120.6077, -5.8892