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
1,651–1,700 of 256,283 · All objects seen in the 7 nights
ObjectClassLast magPeakFirst seenLast seenNightsDetectionsRel.RA, DecPartner
ZTF ZTF18aaacafk EclBinfaded r17.782018-01-112026-09-2614141.00124.8275, 7.3468
ZTF ZTF18aaacarn EclBinfaded r17.832018-01-112026-09-2653781.00122.9837, 8.7050
ZTF ZTF18aaachtd delSctV*faded r15.972018-01-112026-09-2657681.00123.3398, 10.1733
ZTF ZTF18aaachvs RRLyraefaded r14.852018-01-112026-09-2665781.00122.8447, 10.4958
ZTF ZTF18aaachvv RRLyrae19.41 r18.572018-01-112026-09-2632391.00122.6717, 10.6470
ZTF ZTF18aaachya EclBinfaded r17.072018-01-112026-09-2662741.00122.3894, 8.7875
ZTF ZTF18aaacoec RRLyraefaded r17.922017-12-162026-09-2652751.00128.5665, 5.3681
ZTF ZTF18aaacolv Unknown16.13 r15.332018-01-112026-09-26811591.00122.7258, 4.8364
ZTF ZTF18aaagahe EclBinfaded r16.452018-01-132026-09-2656801.00125.8508, 4.7804
ZTF ZTF18aaagasj Unknown15.21 r15.072017-12-182026-09-2640551.00122.9488, 5.5532
ZTF ZTF18aaagazc UnknownAT 2023vrp17.14 r16.912018-01-132026-09-26591.00123.2368, 7.9654
ZTF ZTF18aaaprgq EclBin15.59 r14.952017-12-152026-09-2656781.00129.4575, 6.0238
ZTF ZTF18aaaqmgl EclBinfaded r15.642017-12-182026-09-26660.97125.1417, 9.6528
ZTF ZTF18aabirkf RRLyrae15.21 r14.232017-12-142026-09-2642571.00123.0547, 4.8805
ZTF ZTF18aabitix Unknown13.90 r13.902018-01-132026-09-26661.00124.7394, 5.2200
ZTF ZTF18aabjilw EclBinfaded r17.362017-12-182026-09-2618201.00125.5805, 8.4388
ZTF ZTF18aabjooz RRLyrae18.71 r17.252017-12-182026-09-2664861.00129.4641, 7.7669
ZTF ZTF18aabjpjl EclBinfaded r18.482018-01-112026-09-2635431.00127.7039, 5.5953
ZTF ZTF18aabjwwi EclBinfaded r—2018-01-112026-09-2629411.00127.4590, 5.4857
ZTF ZTF18aabjylp EclBin18.21 r17.922018-01-112026-09-2646511.00124.4333, 10.1791
ZTF ZTF18aabkjlo EclBin17.32 r16.882018-01-132026-09-2640491.00122.4032, 9.3317
ZTF ZTF18aabnexi Unknown16.68 r16.592018-02-112026-09-26751771.00123.3535, 8.2824
ZTF ZTF18aabscgx Starfaded r—2018-02-252026-09-2612131.00124.6015, 10.4815
ZTF ZTF18aabymya EclBinfaded r19.312018-01-112026-09-2615181.00122.7070, 10.9755
ZTF ZTF18aafrlci QSO19.36 r19.362022-10-222026-09-2619201.00125.2433, 8.3300
ZTF ZTF18aafrotm QSO18.29 r17.822018-09-142026-09-2655961.00125.5687, 8.8791
ZTF ZTF18aagfokz Variable*17.80 r17.682018-05-062026-09-2623241.00122.5942, 10.4654
ZTF ZTF18aagfssl LongPeriodV*14.96 r14.452018-04-092026-09-2660701.00123.4883, 9.1985
ZTF ZTF18abwlnes EclBin18.84 r18.822018-01-112026-09-2618181.00122.8259, 9.3826
ZTF ZTF18achdnlm Star17.67 r17.672018-11-102026-09-2643531.00122.5932, 8.6814
ZTF ZTF18aclliya Unknownfaded r14.542018-11-082026-09-26741021.00124.5708, 10.4362
ZTF ZTF18aclludd EclBinfaded r—2018-02-252026-09-26661.00124.2373, 9.6311
ZTF ZTF18aclmjok Unknown18.12 r17.972018-11-132026-09-2654611.00122.4700, 9.4695
ZTF ZTF18acmsuvh Unknown17.97 r17.972018-11-142026-09-2612131.00124.7053, 11.5025
ZTF ZTF18acpofxq EclBinfaded r16.572017-12-162026-09-2633541.00125.3904, 8.0309
ZTF ZTF18acurprm EclBinfaded r18.272018-11-082026-09-2623271.00123.6047, 5.6241
ZTF ZTF18acvhaii Unknownfaded r18.822018-12-122026-09-2621251.00127.5717, 5.8181
ZTF ZTF18acvvtkd Unknownfaded r16.072018-04-022026-09-26581.00125.1965, 7.2690
ZTF ZTF18acvvukz RRLyraefaded r17.722018-01-132026-09-2629401.00126.7956, 6.7914
ZTF ZTF18acvvula AGB*_Candidate14.86 r14.682018-04-022026-09-2631371.00126.3269, 5.9828
ZTF ZTF18acvwhfu Unknown16.71 r16.672018-11-082026-09-26811451.00123.3862, 7.2770
ZTF ZTF18acvwhiq Unknownfaded r17.582018-04-022026-09-2624291.00126.4379, 6.6873
ZTF ZTF18acwwlge EclBinfaded r16.862018-11-052026-09-2633371.00122.5150, 5.7504
ZTF ZTF18acwwlif EclBin18.56 r18.492018-11-072026-09-2644591.00126.3206, 5.7130
ZTF ZTF18acwxmwf Variable*faded r18.322018-11-172026-09-2632431.00126.7383, 7.9308
ZTF ZTF18aczehtt Unknownfaded r17.592018-11-082026-09-26741151.00129.2760, 5.4566
ZTF ZTF18aczehxj Variable*15.03 r14.722018-12-202026-09-26721131.00128.2419, 7.5301
ZTF ZTF18aczeikt Seyfert1AT 2019dcbfaded r18.292018-11-082026-09-26771401.00128.9727, 5.8880
ZTF ZTF18adazbbh Unknown15.84 r15.842018-12-282026-09-26220.27127.7218, 4.9534
ZTF ZTF18adbbrqu QSO18.77 r18.422018-11-022026-09-2665981.00124.4614, 10.6740