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
2,601–2,650 of 214,524 · All objects seen in the 7 nights
ObjectClassLast magRisePeakFirst seenLast seenNightsDetectionsRel.RA, DecPartner
ZTF ZTF20acuvxow EclBinfaded r−0.1—2018-11-052026-09-2911111.00120.7315, 7.0925
ZTF ZTF20acyriht Unknownfaded r−0.5—2018-01-112026-09-29441.00121.7853, 2.1451
ZTF ZTF20acyxeao Unknownfaded r−0.118.222018-11-082026-09-2920271.00122.4429, 4.4387
ZTF ZTF21aabemxn Starfaded r−0.3—2019-01-042026-09-29691611.00121.2557, 0.9353
ZTF ZTF21acckmig Unknown18.18 r+0.118.182018-12-162026-09-29661.00122.5792, 5.9613
ZTF ZTF21acpncgf Unknownfaded r−0.218.882021-10-222026-09-2925271.00123.1462, 5.0165
ZTF ZTF22abrdayn Unknownfaded r−0.2—2020-01-232026-09-2911111.00124.1621, 1.9402
ZTF ZTF23aabgouz EclBin18.07 r+0.117.952017-12-152026-09-29220.92121.0085, 1.2964
ZTF ZTF23abncako Unknownfaded r−0.218.202019-04-252026-09-2910101.00122.6682, 1.1950
ZTF ZTF23abqmdco Unknownfaded r−0.2—2019-11-242026-09-29221.00125.5033, 4.1696
ZTF ZTF24aadilag Unknownfaded r−0.116.402018-12-132026-09-2935381.00125.2797, 3.2560
ZTF ZTF24abqqota EclBinfaded r−0.1—2018-11-192026-09-29661.00124.2972, 3.1611
ZTF ZTF24abrihem Unknownfaded r−0.5—2018-11-072026-09-2923281.00126.5890, 1.9055
ZTF ZTF25aagybeo Unknown19.16 r+0.118.692019-01-262026-09-2919211.00126.4705, 2.8660
ZTF ZTF26aaagmkr Unknownfaded r−0.1—2019-01-042026-09-29551.00125.8762, 4.4380
ZTF ZTF26abvzvkq UnknownSN Ia18.43 r—18.372020-01-062026-09-29331.00121.3722, 5.2352
ZTF ZTF26abwqheb SN candidateAT 2026acri19.03 r+0.319.032026-09-212026-09-29331.00120.9788, 5.4556
ZTF ZTF26abxjlva UnknownAT 2026acxl18.19 r+2.918.192026-09-252026-09-29221.00125.3678, 3.7760
ZTF ZTF26abyannw Solar System MPC17.85 r—17.852026-09-292026-09-29111.00123.5103, 5.1719
ZTF ZTF26abyanqa Solar System MPC18.58 r—18.582026-09-292026-09-29111.00126.1894, 4.2077
ZTF ZTF26abyanrs Solar System MPC18.56 r+2.118.562026-09-292026-09-29111.00125.2149, 3.8686
ZTF ZTF26abyanvw Solar System MPC18.98 r—18.982026-09-292026-09-29111.00121.3041, 3.7873
ZTF ZTF26abyanwa Solar System MPC17.15 r—17.152026-09-292026-09-29111.00122.5536, 7.1632
ZTF ZTF26abyaoji Solar System MPC16.73 r—16.682026-09-292026-09-29121.00120.7347, 0.9173
ZTF ZTF17aaajgdt EclBinfaded r−0.317.132017-12-142026-09-2963891.00124.7741, -5.6036
ZTF ZTF17aabwjrv EclBinfaded r−0.116.732017-12-082026-09-2924291.00121.1110, -5.0072
ZTF ZTF17aabwjsj EclBin17.65 r+0.116.952017-12-082026-09-2962771.00121.2456, 0.1307
ZTF ZTF17aabwjsk EclBinfaded r−0.316.632017-12-082026-09-2953671.00121.1412, -0.9675
ZTF ZTF17aabwjsl RRLyraefaded r−0.316.362017-12-082026-09-29741121.00120.8710, -0.8983
ZTF ZTF17aabwjsn EclBin16.99 r+0.116.832017-12-082026-09-2967971.00121.9055, -4.0499
ZTF ZTF17aabwjtq Unknown17.29 r+0.117.182017-12-082026-09-2948601.00120.9463, -3.1732
ZTF ZTF17aabwjtr EclBinfaded r−0.117.222017-12-082026-09-2933401.00120.5481, -2.8254
ZTF ZTF17aabwjts EclBin17.87 r+0.117.472017-12-082026-09-2936521.00120.7154, -3.3998
ZTF ZTF17aabwjtu EclBin17.55 r+0.217.022017-12-082026-09-2945631.00120.0543, -4.7033
ZTF ZTF17aabwjtv EclBinfaded r−0.314.702017-12-082026-09-2921261.00120.2807, -6.1777
ZTF ZTF17aabwjuc EclBinfaded r−0.117.012017-12-082026-09-2929311.00121.5215, -3.3027
ZTF ZTF17aabwjue RRLyraefaded r−0.216.782017-12-082026-09-29741161.00122.0226, -2.7831
ZTF ZTF17aabwjvf EclBin16.77 r+0.216.762017-12-082026-09-2940591.00118.2944, -3.2594
ZTF ZTF17aabwjvi RRLyraefaded r−0.316.152017-12-082026-09-29721101.00123.8645, -3.3633
ZTF ZTF17aabwjvy RRLyrae14.77 r+0.414.412017-12-082026-09-2948561.00118.6720, -2.4495
ZTF ZTF17aabwjwx EclBinfaded r−0.317.602017-12-082026-09-2936461.00121.2242, -5.7680
ZTF ZTF17aabwkhq Type2Cepfaded r−0.716.542017-12-082026-09-2936531.00118.2808, -3.8923
ZTF ZTF17aabwksz EclBinfaded r−0.316.812017-12-082026-09-2952761.00120.3850, -0.2490
ZTF ZTF17aabwkzi EclBin18.16 r+0.117.382017-12-082026-09-2939591.00118.6625, -2.7877
ZTF ZTF17aabwlan EclBin18.34 r+0.118.262017-12-082026-09-2954661.00118.7793, -1.5818
ZTF ZTF17aabwlhh Unknown18.35 r+2.817.762017-12-082026-09-2912181.00119.6215, -5.0830
ZTF ZTF17aabwlhu EclBinfaded r−0.2—2017-12-082026-09-2918181.00119.4039, -4.7790
ZTF ZTF17aabwljo Unknown16.58 r+0.215.302017-12-082026-09-2956891.00120.2210, -2.5283
ZTF ZTF17aabwnno Unknownfaded r−0.2—2017-12-082026-09-2916201.00118.4641, -6.2723
ZTF ZTF18aaabhol RSCVnV*faded r−0.117.982017-12-082026-09-29591451.00120.2772, 0.9081