🔭 Deep Field (~2.1′ FOV) · DSS2 Optical (China-VO mirror)
● ROTSE3 J125008.3+105456 Explosion Site
High-magnification deep optical view into ROTSE3 J125008.3+105456's host environment. Pan and scroll to explore the cosmic neighborhood where this star exploded.
⚡ Quick Observer Facts & Telemetry
IAU Transients DB🌐 Distance to Earth
Millions of Light-Years
Lookback Cosmic Time
✨ Peak Brightness
Mag 18
Large Observatory
☀️ Peak Radiance
Hundreds of Millions of Suns
Combined Stellar Energy
🚀 Shock Velocity
Not measured
No spectral ejecta velocity
🌌 Host Galaxy
Field Transient Host
Center Coincident
🧭 Constellation
Coma Berenices
Berenice's Hair
💥 Explosion Physics
Type —
Core-Collapse Supergiant
📅 Discovered On
2011/05/22
ROTSE
HISTORIC LANDMARK • JULY 1054 AD
The 'Guest Star' That Created the Crab Nebula
On July 4, 1054 (Song Dynasty, China), court astronomers of Emperor Renzong looked toward the constellation Taurus and documented the sudden appearance of a brilliant "guest star" (客星). Shining four times brighter than Venus, it was visible in broad daylight for 23 consecutive days and remained visible to the unaided eye in the night sky for nearly two years.
★ Landmark Dossier: SN 1054 (The Crab Supernova)
Historical Observers: Song Dynasty Astronomers, Arab Astronomer Ibn Butlan, Ancestral Puebloan Rock Art •
Distance: ~6,500 Light-Years •
Peak Apparent Magnitude: m ≈ −6.0 (Visible in Daylight) •
Surviving Remnant: Messier 1 (The Crab Nebula) & PSR B0531+21 (30 Hz Pulsar)
Records of SN 1054 were scrupulously transcribed in the Song Shi (History of Song) and the Wenxian Tongkao, alongside independent medical and astronomical writings by the Christian Arab physician Ibn Butlan in Baghdad. Across the Atlantic Ocean, pictographs at Chaco Canyon in New Mexico depict a crescent moon adjacent to a ten-pointed star, believed to commemorate the July 5, 1054 conjunction.
THE BIRTH OF A PULSAR
The Discovery of the Crab Pulsar & Modern High-Energy Physics
Seven centuries later, in 1731, English amateur astronomer John Bevis discovered a faint glowing cloud at the exact celestial coordinates: what Charles Messier would later catalog as Messier 1 (M1), the Crab Nebula.
In 1968, radio astronomers discovered the beating heart of the Crab: PSR B0531+21, a rapidly rotating neutron star spinning 30.2 times per second with a magnetic field of nearly 4 trillion Gauss. The Crab Pulsar continuously injects relativistic electrons and positrons into the nebula, illuminating the intricate filamentary tendrils of ionized gas across every band of the electromagnetic spectrum—from radio waves to ultra-high-energy teraelectronvolt (TeV) gamma rays!
BACKYARD OBSERVATION
Locating the Crab Nebula in Taurus
While the optical outburst faded into history nine centuries ago, the expanding remnant nebula is one of the most popular showpieces
for amateur telescopes under dark skies. Located near the southern horn of Taurus the Bull (RA 12:50:08.33,
Dec +10:54:56.2), an 8-inch telescope reveals its eerie oval ghostly glow, expanding at 1,500 kilometers every second.
Can I see it tonight? Unknown — no measured brightness.
Discovered 15.5 years ago (2011/05/22). No reliable current brightness estimate — no photometry has been published.
🌌 Cosmic Neighbors & Contemporaries
105,768+ transients indexed
Cataloged transients closest to ROTSE3 J125008.3+105456 in discovery time, spatial sky neighborhood, and cosmological redshift:
⏱️ Closest in Time
SN2011de
Exploded same day
Type Ia Pec?
2011/05/22 · Mag 15.05
PSc170076
1d before
Type Ia
2011/05/21 · Mag 21.57
PSc170240
1d before
Type Ia
2011/05/21 · Mag 19.77
🔭 Closest on the Sky
AT2021nff
14.9′ away
Type Candidate
Discovered 2021/04/11
SN2024jfy
23.1′ away
Type Ia
Discovered 2024/05/23
AT2020fin
40.3′ away
Type Candidate
Discovered 2020/03/28
🌌 Same Cosmic Era (Redshift)
No redshift match available (target z missing or no comparable redshifts in index).
❓ Frequently Asked Questions About ROTSE3 J125008.3+105456
Scientific & observational Q&As indexed from astronomical databases & the Open Supernova Catalog
What type of supernova is ROTSE3 J125008.3+105456 and what kind of star exploded? Astrophysics & Progenitor
ROTSE3 J125008.3+105456 has not been spectroscopically classified. It was reported as an astronomical transient, which means an object was detected changing in brightness, but its nature is not yet established. Classification requires a spectrum: the presence or absence of hydrogen lines separates Type II from Type I, and Type Ia is identified by silicon absorption near 6150 Å combined with the absence of hydrogen. Until such a spectrum is published, claims about the progenitor star or explosion mechanism would be speculation. Check the sources below for follow-up spectroscopy.
What was the progenitor star doing in the millions of years leading up to ROTSE3 J125008.3+105456? Astrophysics & Progenitor
The progenitor of ROTSE3 J125008.3+105456 cannot be identified without a classification. Stellar evolutionary history depends entirely on the explosion type: a Type Ia event would require a carbon-oxygen white dwarf in a binary system, whereas a core-collapse event would require a massive star exhausting its fuel within tens of millions of years. These are mutually exclusive histories that produce different spectra and light curves. No progenitor or precursor has been reported for this transient in the available literature.
How far away is ROTSE3 J125008.3+105456 from Earth and how old is the light reaching us? Cosmic Distance & Time
The distance to ROTSE3 J125008.3+105456 has not been measured. No spectroscopic redshift or luminosity distance is published for this transient, so neither its distance from Earth nor its lookback time can be stated. A redshift requires a spectrum, and a photometric redshift requires multi-band imaging that has not been reported. Without a distance, its intrinsic luminosity and total energy release are also undetermined. Check the sources below for follow-up spectroscopy or host-galaxy identification.
What does the cosmological redshift of ROTSE3 J125008.3+105456 tell us about the expansion of space? Cosmic Distance & Time
No spectroscopic redshift has been measured for ROTSE3 J125008.3+105456. Without a published z, its place in the Hubble flow, recession velocity, and lookback time cannot be stated. A redshift requires a spectrum (or a well-calibrated photometric redshift from multi-band imaging). Check the sources below for follow-up spectroscopy.
How bright did ROTSE3 J125008.3+105456 become at its peak, and how many Suns does that equal? Explosion Energetics
At peak brightness, ROTSE3 J125008.3+105456 achieved an apparent magnitude of 18 around 2011/05/21.
How much total energy was released by ROTSE3 J125008.3+105456, and where did that energy go? Explosion Energetics
The total energy released by ROTSE3 J125008.3+105456 is unknown. Energy budgets differ by orders of magnitude depending on mechanism: a thermonuclear Type Ia liberates ~10⁵¹ ergs mostly as kinetic energy, while a core-collapse event liberates ~10⁵³ ergs of which ~99% escapes as neutrinos. Without a spectroscopic classification, neither figure applies to this transient.
How fast are the supernova ejecta and shockwave of ROTSE3 J125008.3+105456 expanding through space? Explosion Energetics
No ejecta velocity is measured for ROTSE3 J125008.3+105456. Blast-wave speed is obtained from Doppler shifts of spectral absorption features (e.g. Si II λ6355 for Type Ia), not from cosmological redshift. Any recession velocity derived from z describes Hubble flow, not the explosion debris.
What powers the prolonged glow of ROTSE3 J125008.3+105456 weeks and months after detonation? Radioactive Engine
The power source sustaining ROTSE3 J125008.3+105456 cannot be identified without a classification. Classified supernovae are typically powered after peak by the radioactive decay of ⁵⁶Ni → ⁵⁶Co → ⁵⁶Fe, but nickel yields and whether a shock-breakout flash occurred depend on the explosion mechanism. No spectrum is published for this transient, so no ⁵⁶Ni mass or decay-powered light-curve narrative applies.
What chemical elements did ROTSE3 J125008.3+105456 create and disperse into the universe? Nucleosynthesis & Elements
The nucleosynthetic products of ROTSE3 J125008.3+105456 are unknown because its type is unresolved. Element yields depend directly on the explosion mechanism: a thermonuclear Type Ia produces mostly iron-peak elements such as 56Ni and 56Fe, whereas a core-collapse event produces large quantities of oxygen, neon, magnesium and silicon from successive burning shells. No spectrum has been published for this transient, so which of these occurred is not established.
Did ROTSE3 J125008.3+105456 leave behind a black hole, a neutron star, or nothing at all? Cosmic Remnant
Whether ROTSE3 J125008.3+105456 left a remnant is unknown. A thermonuclear Type Ia leaves no compact remnant (the white dwarf is fully disrupted), whereas a core-collapse event leaves a neutron star or black hole depending on progenitor mass. Without a spectroscopic classification, none of these outcomes can be asserted for this transient.
What will ROTSE3 J125008.3+105456's explosion site look like in 1,000 to 10,000 years? Cosmic Remnant
Supernova remnants in general evolve through free-expansion, Sedov–Taylor, and radiative phases over centuries to millennia, sometimes becoming bright X-ray shells and occasionally compressing nearby molecular clouds. These are standard remnant-evolution models, not forecasts measured for ROTSE3 J125008.3+105456. Whether this site will trigger star formation, reach particular X-ray temperatures, or match Cassiopeia A depends on local density and magnetic field—none of which are constrained by the data shown here.
In which galaxy did ROTSE3 J125008.3+105456 explode, and where is it located relative to the galactic center? Galactic Environment
No host galaxy is identified for ROTSE3 J125008.3+105456 in this catalog record. A blank host field means the association is unresolved here—it does not establish that the host is uncataloged, resolved in imaging, or securely linked by astrometry. Possible states (unidentified, hostless candidate, imaging detection without a catalog name, or a securely matched cataloged galaxy) require separate evidence that is not present in this field.
Where is ROTSE3 J125008.3+105456 located in the night sky and which constellation is it in? Sky Coordinates
In the celestial sphere, ROTSE3 J125008.3+105456 is located at Right Ascension 12:50:08.33 and Declination +10:54:56.2, situated in the constellation Coma Berenices (Berenice's Hair). Because its declination is +10:54:56.2, it is primarily placed in the Northern celestial hemisphere.
How much Milky Way interstellar dust obscures our view of ROTSE3 J125008.3+105456? Interstellar Dust
Along this line of sight, the catalog records a Milky Way foreground color excess of E(B−V) = 0.0212 mag (source: published extinction estimate), corresponding to roughly A_V ≈ 0.07 mag for R_V = 3.1. Band-specific corrections (e.g. A_r) differ from A_V and should be applied when available. Map-based values (IRSA / Schlafly & Finkbeiner 2011) must not be claimed unless that map was actually queried.
Across which photometric filter bands was ROTSE3 J125008.3+105456 monitored? Astronomical Observations
No calibrated photometry is published for ROTSE3 J125008.3+105456. Without multi-epoch flux measurements, neither a light curve nor a peak magnitude can be established. Follow-up imaging from survey alert streams would be required to map its brightness evolution.
What did astronomical spectroscopy reveal about ROTSE3 J125008.3+105456's chemical makeup? Astronomical Observations
No spectrum has been published for ROTSE3 J125008.3+105456. Without spectroscopy, its chemical composition, expansion velocity, and physical classification cannot be established. Classification spectra from follow-up observatories would be required to identify diagnostic absorption and emission lines.
Who discovered ROTSE3 J125008.3+105456 and how was it first detected? Discovery & History
ROTSE3 J125008.3+105456 was officially reported on 2011/05/22 by ROTSE. Discoveries are typically flagged by high-cadence robotic survey telescopes (such as ATLAS, ZTF, Pan-STARRS, ASAS-SN, or Gaia) and worldwide amateur astronomers scanning the night sky, followed by rapid spectroscopic classification by international observatories.
How many scientific publications and observatories have contributed data to ROTSE3 J125008.3+105456? Scientific Research
Data for ROTSE3 J125008.3+105456 are compiled from international astronomical notices, the IAU Transient Name Server (TNS), and peer-reviewed astrophysical journals.
How does ROTSE3 J125008.3+105456 contribute to measuring the Hubble Constant and the scale of the cosmos? Cosmology & Distance Ladder
ROTSE3 J125008.3+105456 cannot currently be used for cosmological distance work because its classification is unresolved. The distance ladder relies on type-specific techniques: Type Ia supernovae use the Phillips relation between peak absolute magnitude and decline rate, while Type II events use the Expanding Photosphere Method or SCM-II. An unclassified transient fits neither, so no Hubble-constant constraint can be derived from it until a spectrum establishes its type.
Could gravitational waves or neutrinos from ROTSE3 J125008.3+105456 be detected on Earth? Multi-Messenger Astronomy
No neutrino or gravitational-wave counterpart has been reported for ROTSE3 J125008.3+105456, and none is expected to be identifiable without a classification. The multi-messenger signature differs sharply by type: core-collapse events emit a neutrino burst at shock breakout (detected once, for SN 1987A), while thermonuclear Type Ia events produce negligible neutrinos and gravitational waves. Searching for a counterpart before knowing which mechanism applies would be unfocused.
How does ROTSE3 J125008.3+105456 compare to famous historical supernovae like SN 1987A or the Crab Supernova? Historical Comparison
Compared to historical landmarks like SN 1987A in the Large Magellanic Cloud (168,000 light-years away, naked-eye peak m = 2.9) or the Crab Supernova of 1054 (6,500 light-years away), the distance to ROTSE3 J125008.3+105456 is not established for a historical comparison (unclassified; no redshift or luminosity distance is published). While historical naked-eye supernovae occurred within our Milky Way or its immediate satellites, modern discoveries like ROTSE3 J125008.3+105456 allow astrophysicists to probe diverse galactic environments, metallicities, and stellar populations across the broader universe.
Can I see ROTSE3 J125008.3+105456 tonight with a backyard telescope or binoculars? Backyard Observation
Unknown — no measured brightness. ROTSE3 J125008.3+105456 was discovered 5646 days ago (2011/05/22), but no calibrated photometry is published for it, so its current apparent magnitude cannot be stated. Without a magnitude there is no basis for a telescope-aperture recommendation. Use the coordinates and airmass chart above to plan a follow-up observation and report what you measure.
Does the radiation or shockwave from ROTSE3 J125008.3+105456 pose any threat to Earth? Planetary Safety
Earth is in no danger from ROTSE3 J125008.3+105456. The astrophysical 'lethal kill zone' for a supernova to damage our ozone layer is roughly 50 to 100 light-years. This transient is far outside the solar neighbourhood: it was discovered by a wide-field survey at a magnitude only reachable for an extragalactic object, and any transient in our own galaxy within that radius would have appeared far brighter than the ~18th magnitude reported here. Its exact distance is unmeasured, but the detection brightness alone rules out any nearby threat.
Data sourced from IAU TNS, ALeRCE, WISeREP, and the Open Supernova Catalog.
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