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. A nova or CV brighter than 14 also gets AAVSO's observers' V for two months: the median of a sample of each night's observations (the tooltip says of how many). 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.
  • ASAS-SN: discoveries on the All-Sky Automated Survey for Supernovae's list of transients that nothing above has, mostly cataclysmic variables in outburst (ASASSN-26fg). Each detection is a magnitude the list quotes, in g. An object that matches one shows its ASAS-SN name.
  • 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, CBAT or ASAS-SN object neither ATLAS nor AAVSO measures (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.
  • More filters (Objects only): discovered within some nights, a redshift ceiling, a declination band, a faint limit past your saturation, one-night objects, rising ones, a reporting survey, or those an AAVSO campaign asks for. A view can be named, and its Subscribe panel gives it as a feed, as JSON and as targets for a TOM.

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.
  • Where your data count: the surveys measure their own objects every few nights, but a TNS, CBAT or ASAS-SN object gets only ATLAS's photometry while it is brighter than 19, and AAVSO's nightly V if it is a nova or CV brighter than 14. Unconfirmed marks one reported on a single night in the last two weeks: a detection confirms it, and a deep non-detection is news too. No recent data marks one seen on two or more nights that nothing has measured for four nights or more: a magnitude fills the gap in its light curve. Requested marks one an AAVSO observing campaign asks observers to measure; Campaigns tonight lists the other campaign stars that are up.
  • Report an observation (object panel): where your photometry and spectra go (AAVSO for stars and Galactic novae, TNS for supernovae and novae in nearby galaxies, CBAT for an unconfirmed TOCP entry; an AGN only to AAVSO when VSX lists it, and to TNS when it flares), the name to file them under from AAVSO's VSX, and an AAVSO file formatted from what you type. Nothing is sent from the site; your observer code stays in this browser.

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

Every source and the credit it asks for are on Data and API.

Everything here is also JSON: Data and API has the public API, the feeds, the exports and how to cite the data.

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.

Contact us: [email protected]

Objects

Objects
Source
Bucket
More filters
Clear
1–50 of 221,828 · All objects seen in the 7 nights
ObjectClassLast magRisePeakFirst seenLast seenNightsDetectionsRel.RA, DecPartner
TNS AT 2026abeq Unknown · M3119.30 o—17.182026-09-112026-10-01811—10.5532, 41.2746
ASAS-SN ASASSN-26ff CataclyV*_Candidate17.85 o—15.702026-09-162026-10-0167—0.6420, 52.9220
TNS AT 2026abpy Unknown19.54 o—18.502026-09-102026-10-01912—341.8228, 27.3093
TNS AT 2026acnc Unknown18.91 o—18.912026-09-202026-10-0122—125.5429, -19.9766
TNS SN 2026acxb SN candidateSN Ia18.50 o—17.462026-09-112026-10-011111—311.9115, 27.0933
TNS AT 2026aciq Unknown19.05 o—18.762026-09-112026-10-01910—91.6214, -31.9859
ASAS-SN ASASSN-26fg CataclyV*_Candidate17.92 o—16.002026-09-192026-10-0177—69.8227, -28.1034
TNS AT 2026abxn Unknown18.25 c—16.292026-09-152026-10-0177—284.0373, 47.3793
TNS SN 2026abqh SN candidateSN Ia18.13 c—18.132026-09-122026-10-01710—241.6381, 47.4463
TNS AT 2026abuu Unknown19.17 c—18.512026-09-122026-10-0189—246.2499, 47.8470
TNS AT 2026abms Unknown17.95 c—17.852026-09-112026-10-01811—227.4572, 32.1936
ZTF ZTF20acbbwwy Unknown19.29 g+0.519.292019-07-122026-10-0142441.00343.0116, -19.4723
ZTF ZTF22aaspmnl Unknownfaded g−0.318.932019-01-102026-10-0148601.00342.6701, -19.7233
ZTF ZTF26abyjanv Solar System MPC16.97 g—16.972026-10-012026-10-01111.00343.2220, -20.1002
ZTF ZTF26abyjanw Solar System MPC18.76 g—18.762026-10-012026-10-01111.00343.1162, -20.7327
ZTF ZTF26abyjbex Solar System MPC17.75 g—17.752026-10-012026-10-01111.00342.9853, -19.8608
ZTF ZTF26abyjbey Solar System MPC18.58 g—18.582026-10-012026-10-01110.99342.7307, -19.0633
ZTF ZTF26abyjbfi Solar System MPC19.94 g—19.942026-10-012026-10-01111.00343.2173, -19.5385
ZTF ZTF26abyjbfl Solar System MPC19.81 g—19.812026-10-012026-10-01110.99343.0923, -19.0638
ZTF ZTF18acbxhod Unknownfaded g−0.5—2018-07-212026-10-0111121.00337.5422, -26.8183
ZTF ZTF18accgnru Unknownfaded g−0.517.862018-07-212026-10-0141451.00337.9589, -23.0202
ZTF ZTF18accgocj Unknownfaded g−0.215.962018-07-212026-10-0148591.00336.2281, -23.6451
ZTF ZTF18accgocl Unknownfaded g−0.617.662018-07-212026-10-0153631.00336.0040, -23.8584
ZTF ZTF18accgocn Unknownfaded g−0.2—2018-07-242026-10-01881.00335.9806, -23.8610
ZTF ZTF18accgopd Unknownfaded g−0.416.242018-07-242026-10-0126321.00335.9475, -26.7638
ZTF ZTF18acdjqik Unknownfaded g−0.418.122018-07-212026-10-0139461.00337.7779, -23.7979
ZTF ZTF18acetlyr Unknown15.77 g+0.813.492018-07-212026-10-0160821.00337.9381, -23.5461
ZTF ZTF18acfbvdu Unknownfaded g−0.215.852018-08-012026-10-0134371.00341.9176, -27.5505
ZTF ZTF18acfbvfc Unknownfaded g−0.316.872018-08-012026-10-0137401.00341.2174, -27.5263
ZTF ZTF18acfbxse Unknownfaded g−0.318.292018-07-212026-10-0135401.00339.5480, -27.6899
ZTF ZTF18acfeuty Unknown17.77 g+0.115.692018-07-212026-10-0151621.00338.3484, -23.6164
ZTF ZTF18acgzjku Unknownfaded g−0.317.762018-07-212026-10-0125271.00338.6056, -23.7726
ZTF ZTF18achgsba Unknown19.07 g+0.217.622018-07-212026-10-0133381.00340.6873, -27.2788
ZTF ZTF18achgszo Unknownfaded g−0.4—2018-07-212026-10-01551.00336.6938, -27.0431
ZTF ZTF18achgtrl Unknownfaded g−0.4—2018-11-122026-10-01111.00337.8929, -22.8603
ZTF ZTF18actwwue Unknown17.69 g+0.517.692018-07-212026-10-0121221.00336.7920, -27.4790
ZTF ZTF18adoedaq Unknown18.29 g+0.417.022018-07-212026-10-0124281.00339.6882, -26.4280
ZTF ZTF18adoedbz Unknown18.93 g+0.318.032018-07-212026-10-0115181.00340.3570, -26.6098
ZTF ZTF19abdkank Unknownfaded g−0.217.622018-07-242026-10-01991.00337.7311, -27.7525
ZTF ZTF19abdkaon UnknownAT 2020krh18.97 g+0.718.552019-07-032026-10-0115241.00335.8592, -22.7567
ZTF ZTF19abdkati Unknownfaded g−0.318.772018-07-242026-10-0121251.00340.9177, -27.5153
ZTF ZTF19abdkbtm UnknownAT 2018gltfaded g−1.219.342018-07-212026-10-0129291.00338.0639, -23.7872
ZTF ZTF19abdkbuk Unknownfaded g−0.318.652019-07-032026-10-0128381.00337.7404, -26.8515
ZTF ZTF19abdlela Unknownfaded g−0.916.932018-07-212026-10-0117171.00337.8241, -27.9052
ZTF ZTF19abegkie Unknown18.82 g+0.318.672019-07-032026-10-0130371.00335.3506, -27.3831
ZTF ZTF19abegkjs Unknownfaded g−0.116.782018-07-212026-10-0137471.00338.1920, -22.8603
ZTF ZTF19abegzhr Unknownfaded g−0.318.582018-07-212026-10-0110111.00337.5711, -26.4004
ZTF ZTF19abfzbvf Unknownfaded g−0.413.612018-07-212026-10-0139501.00341.9218, -27.1561
ZTF ZTF19abizwnh Unknown17.95 g+0.617.292018-11-122026-10-0172991.00338.1381, -23.2048
ZTF ZTF19ablnltq Unknownfaded g−0.318.472019-07-272026-10-0156741.00341.9214, -27.8509