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
1,801–1,850 of 256,283 · All objects seen in the 7 nights
ObjectClassLast magPeakFirst seenLast seenNightsDetectionsRel.RA, DecPartner
ZTF ZTF17aaantxj CataclyV*16.89 r14.612017-12-142026-09-26861511.00129.0798, 21.3514
ZTF ZTF17aaaomic EclBinfaded r14.162017-12-152026-09-2634431.00127.0934, 19.1688
ZTF ZTF17aaaomns EclBinfaded r16.402017-12-142026-09-2660791.00124.5012, 22.3848
ZTF ZTF17aaaomps Unknown17.76 r16.932017-12-082026-09-2640511.00125.7809, 22.7140
ZTF ZTF17aaaomuj EclBinfaded r16.882017-12-152026-09-2653641.00128.6412, 21.5531
ZTF ZTF17aaaomvd EclBinfaded r18.142017-12-152026-09-26331.00125.6118, 23.6615
ZTF ZTF17aaaonaw EclBin18.82 r18.472017-12-152026-09-2648561.00124.1393, 21.8969
ZTF ZTF17aaapaiq EclBinfaded r17.822017-12-142026-09-2651651.00124.0205, 19.2361
ZTF ZTF17aaayzci EclBinfaded r16.772017-12-142026-09-2615171.00124.3140, 21.6480
ZTF ZTF17aaazdba SeyfertTDEfaded r—2017-12-172026-09-26110.99123.3205, 22.6482
ZTF ZTF17aaazddy Unknownfaded r—2017-12-172026-09-26110.26123.1870, 22.6991
ZTF ZTF17aaazemd NearIRfaded r—2018-11-202026-09-26110.64124.2340, 22.7999
ZTF ZTF17aabqnhi RRLyraefaded r19.192017-12-152026-09-26661.00127.0025, 21.3753
ZTF ZTF17aabqoxu RRLyraefaded r15.202017-12-142026-09-2660981.00125.5383, 20.1372
ZTF ZTF17aacpbzn Type2Cep14.69 r14.082017-11-092026-09-2661821.00124.4832, 23.4540
ZTF ZTF18aaabpfy Variable*17.17 r17.122017-12-142026-09-2647701.00126.9456, 21.9843
ZTF ZTF18aaaioez Unknown17.90 r17.292018-05-062026-09-2631361.00124.0792, 19.0963
ZTF ZTF18aaasozv EclBinfaded r18.532017-12-152026-09-2627351.00122.9970, 22.0364
ZTF ZTF18aaaspcm EclBinfaded r17.892017-12-152026-09-266141.00123.1859, 18.8646
ZTF ZTF18aaaspfl EclBin18.37 r18.372017-12-142026-09-2654641.00122.7385, 19.7634
ZTF ZTF18aaatonm EclBin18.89 r18.892017-12-152026-09-26621001.00127.6761, 21.0808
ZTF ZTF18aaaxiah RSCVnV*faded r16.512017-12-082026-09-2622321.00126.3038, 22.6764
ZTF ZTF18aabsmml RSCVnV*faded r17.442018-03-052026-09-2654851.00123.4723, 21.5388
ZTF ZTF18aabvqoj EclBinfaded r18.032017-12-142026-09-2623271.00123.3125, 21.0702
ZTF ZTF18aafacod QSOfaded r18.272018-09-112026-09-261012591.00125.1010, 23.5806
ZTF ZTF18aafmjsv QSO19.01 r18.952018-11-122026-09-26882261.00127.5060, 19.9463
ZTF ZTF18aafojcz Unknown18.19 r18.192018-11-032026-09-2616161.00127.4922, 22.3629
ZTF ZTF18aafvxfm Unknown18.25 r18.252017-12-172026-09-26110.17126.7573, 18.8487
ZTF ZTF18aafvxky Unknown18.58 r18.582026-09-262026-09-26110.87126.6549, 18.9727
ZTF ZTF18aagdogl Unknownfaded r18.692018-11-012026-09-26771.00123.5527, 24.0935
ZTF ZTF18aagggmt Unknown17.97 r17.662018-04-152026-09-2660881.00125.6053, 22.2964
ZTF ZTF18aaghykd QSO18.33 r18.272017-12-172026-09-2649681.00126.2373, 21.9276
ZTF ZTF18aagicjg QSO18.87 r18.292019-10-232026-09-26932271.00126.0788, 22.4430
ZTF ZTF18aagjzvz Star15.98 r15.982018-11-142026-09-26110.12124.5629, 19.7307
ZTF ZTF18aagkaqo Unknown16.93 r16.932018-11-142026-09-26110.01124.8074, 19.8489
ZTF ZTF18aagkdqd Unknown19.00 r19.002023-12-182026-09-26110.99123.6481, 19.7668
ZTF ZTF18aagkfoo Unknown17.63 r17.632018-11-052026-09-26110.69124.7492, 19.6960
ZTF ZTF18aagkhpk Unknown18.53 r18.532018-11-052026-09-26110.99124.7071, 19.7613
ZTF ZTF18aagkipu Starfaded r17.952018-04-192026-09-2626401.00124.1045, 19.5041
ZTF ZTF18aagksbu RadioGfaded r19.002017-12-172026-09-26220.90123.9965, 20.4974
ZTF ZTF18aagkskg Unknownfaded r—2026-09-262026-09-26110.95124.2070, 20.3512
ZTF ZTF18aagkxin BYDraV*faded r18.302018-02-252026-09-26221.00126.8947, 21.3359
ZTF ZTF18aagkyjg Unknown17.58 r17.252017-12-172026-09-26631171.00127.3361, 21.1842
ZTF ZTF18aagovnz Starfaded r—2018-11-122026-09-26111.00123.8012, 21.5156
ZTF ZTF18aagoykk Unknownfaded r—2018-12-032026-09-26110.77123.2042, 21.7551
ZTF ZTF18aagpppv Unknown18.72 r18.722019-01-292026-09-26110.82126.9225, 19.1219
ZTF ZTF18aajwpgw Unknown16.61 r16.612018-04-152026-09-26110.80124.6485, 19.9107
ZTF ZTF18abxbmks BLLac18.31 r18.112018-05-252026-09-26681181.00125.2133, 23.8960
ZTF ZTF18achzjix Unknown18.94 r18.302018-01-142026-09-26631091.00127.5929, 20.2301
ZTF ZTF18acljchg AGN_Candidatefaded r—2018-11-202026-09-26110.91124.1177, 23.8107