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.
  • Tonight: Subscribe gives an RSS feed of your setup, one item a night with the picks, once the data through the night before are in (or three hours before dark). A condition (novae, rare types, something brighter than a magnitude) leaves nights without a match out, so a feed-to-email service mails only those. The plan is also JSON, for scripts and robotic telescopes. A feed's address holds your rounded site and setup: a reader or email service you give it to keeps it.

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
3,451–3,500 of 212,839 · All objects seen in the 7 nights
ObjectClassLast magRisePeakFirst seenLast seenNightsDetectionsRel.RA, DecPartner
ZTF ZTF18adpoxcm RRLyrae16.92 r+0.316.442018-06-102026-09-3055731.00331.0877, -14.7346
ZTF ZTF18adpoxjp EclBinfaded r−0.2—2018-06-162026-09-30661.00331.1716, -17.7752
ZTF ZTF18adpoxko RRLyraefaded r−0.216.492018-06-102026-09-3053591.00331.5646, -14.9831
ZTF ZTF18adpoyqh RRLyrae17.54 r+0.316.312018-06-102026-09-3061761.00331.5157, -18.0949
ZTF ZTF18adptktz EclBinAT 2022olc17.99 r+0.217.692018-06-282026-09-3049591.00332.5281, -18.4037
ZTF ZTF19aaaabfm EclBin17.82 r+0.217.572018-06-102026-09-3022221.00333.2159, -20.0999Rubin
ZTF ZTF19aaaafbo RRLyrae19.27 r+0.218.962018-06-102026-09-3036381.00333.6869, -18.4443Rubin
ZTF ZTF19aaaagxl Unknown18.79 r+0.117.822018-08-082026-09-3021241.00330.9169, -13.7351
ZTF ZTF19aaafvyu EclBinfaded r−0.216.392018-06-102026-09-3011151.00330.6256, -15.7401
ZTF ZTF19aaafyki Starfaded r−0.2—2018-06-102026-09-30991.00330.5487, -17.2238
ZTF ZTF19aaasnay Unknownfaded r−0.118.182019-01-052026-09-30881.00330.9952, -14.9102
ZTF ZTF19aacaujs Unknownfaded r−0.116.642018-08-012026-09-3016211.00336.6553, -20.3409
ZTF ZTF19aayijii LongPeriodV*15.58 r+0.315.582018-06-102026-09-3026311.00335.4361, -20.3695
ZTF ZTF19aayijku AGN19.55 r+0.419.042019-06-082026-09-3059851.00332.9257, -14.9433
ZTF ZTF19aayijuw AGN_CandidateAT 2019jygfaded r−0.418.912018-06-102026-09-3064951.00330.4387, -17.2138
ZTF ZTF19aayikft AGNfaded r−0.318.382019-06-082026-09-3066831.00336.0167, -19.2851
ZTF ZTF19aazcchz AGN19.10 r+0.318.862019-06-082026-09-30781171.00335.5058, -19.3476Rubin
ZTF ZTF19aazcclj Unknown19.39 r+0.616.132018-08-122026-09-3022271.00334.3501, -19.6646Rubin
ZTF ZTF19abdjsrk Unknownfaded r−0.216.882018-06-162026-09-3070961.00333.8656, -18.2364
ZTF ZTF19abdjuak Unknownfaded r−0.217.782018-07-242026-09-3011151.00330.6495, -14.9179
ZTF ZTF19abdkntl Unknownfaded r−0.1—2019-07-032026-09-30220.99331.4365, -18.4374
ZTF ZTF19abegebk EclBin18.27 r+0.118.272018-09-082026-09-30220.99332.0420, -16.0323
ZTF ZTF19abhqrpi Unknownfaded r−0.116.832018-11-112026-09-3027321.00336.9537, -18.6938
ZTF ZTF19abnfawa QSOfaded r−0.119.032019-08-042026-09-30781.00332.2170, -19.7335
ZTF ZTF19abnfdpc EclBin14.84 r+0.214.172018-06-282026-09-3030381.00332.7811, -19.5257
ZTF ZTF19acbybhz bluefaded r−0.218.582018-09-042026-09-30721171.00336.9230, -17.2164
ZTF ZTF19acbycsd Unknownfaded r−0.1—2019-09-212026-09-30110.27331.4088, -20.5149
ZTF ZTF19acrkonz Unknown16.99 r+0.216.802018-06-102026-09-3039491.00332.6622, -18.7996
ZTF ZTF19adalkow Unknown17.91 r+0.217.892018-07-242026-09-30551.00332.4746, -17.8274
ZTF ZTF19adddwym QSOfaded r−0.2—2019-06-082026-09-3027321.00332.7007, -19.2136
ZTF ZTF19adddxiq AGNfaded r−0.218.552019-01-042026-09-3037411.00331.0761, -18.6135
ZTF ZTF19adddyxs AGNfaded r−0.518.502019-06-082026-09-30901381.00329.9796, -14.5009Rubin
ZTF ZTF19adlioki Unknownfaded r−0.2—2019-06-272026-09-3011111.00329.7294, -16.2140Rubin
ZTF ZTF20aadzqax Solar System MPC18.42 r—18.422020-01-062026-09-30111.00332.5478, -14.6966
ZTF ZTF20abgdfbz Blazar18.41 r+0.818.352019-07-262026-09-30982311.00330.0323, -19.7631Rubin
ZTF ZTF20abivirs AGN19.22 r+0.519.012020-06-272026-09-30631011.00330.6119, -18.5197Rubin
ZTF ZTF20abivirt QSO18.63 r+0.318.602020-06-272026-09-3058721.00331.0064, -18.3282
ZTF ZTF20abkhuno Unknownfaded r−0.219.012020-07-102026-09-3050591.00330.8493, -14.4458
ZTF ZTF20abllbzd QSOfaded r−0.319.442020-06-272026-09-3048631.00332.0163, -19.9994
ZTF ZTF20ablldcy Unknownfaded r−0.319.362018-11-212026-09-3032321.00331.6614, -14.1494Rubin
ZTF ZTF20abmbngk Unknown19.23 r+0.419.022020-07-132026-09-30721011.00330.3764, -16.8508Rubin
ZTF ZTF20abmysrl Unknownfaded r−0.118.972018-06-162026-09-3032341.00333.0277, -16.7250
ZTF ZTF20aboppsu AGN19.38 r+0.219.272020-07-252026-09-3018201.00333.0415, -15.8942Rubin
ZTF ZTF20acmyulf Unknown18.10 r+0.118.102019-10-052026-09-30661.00332.8486, -20.1229
ZTF ZTF20acpjknr EmLine*faded r−0.1—2018-06-102026-09-30330.81330.4770, -17.4367
ZTF ZTF20acpphlq AGN19.04 r+0.418.822020-10-232026-09-30851361.00332.7152, -16.0539
ZTF ZTF20acubafx Unknownfaded r−0.115.252019-12-202026-09-30770.97330.5966, -15.5388
ZTF ZTF21aaapwsi RRLyraefaded r−0.1—2018-06-102026-09-30221.00330.5535, -17.7465
ZTF ZTF21abdvdeb Unknownfaded r−1.418.882019-06-082026-09-30721131.00330.0651, -17.1455Rubin
ZTF ZTF21abfxome Unknown19.38 r+0.319.272020-10-212026-09-3018181.00332.2092, -14.6017