Tycho's Supernova Remnant (SN 1572 / 3C 10 / SNR G120.1+01.4)
Coordinates, distance (2.8 kpc / 9,100 ly), SN 1572 Type Ia light-echo spectrum, Chandra X-ray stripes, and data for Tycho's SNR in Cassiopeia.
Provenance-Backed Scientific Measurements
Every measurement below preserves its unit, uncertainty interval, observational method, reference epoch, quality status, and primary catalog source. See Uncertainty & Provenance for how competing measurements are handled.
| Parameter | Value | Uncertainty | Method & Epoch | Quality Status | Source Archive |
|---|---|---|---|---|---|
| Optical Balmer-filament integrated magnitude | 15.5 mag | ± 0.8 mag | Deep H-alpha non-radiative shock filament integration (1572 peak was V = −4.0) | model-dependent | SIMBAD Astronomical Database (CDS) |
| Heliocentric distance | 9130 ly | ± 1000 ly | Proper motion of Balmer shocks + Type Ia peak luminosity & H I absorption (2.8 ± 0.3 kpc) (J2016.0) | high-confidence | SIMBAD Astronomical Database (CDS) |
| Apparent X-ray and radio shell diameter | 8 arcmin | ± 0.3 arcmin | Chandra X-ray and VLA radio forward blast wave (8.0′ × 8.0′) | definitive | SIMBAD Astronomical Database (CDS) |
J2000 Equatorial Sky Chart & Culmination Altitude
The chart below plots Tycho's Supernova Remnant (SN 1572 / 3C 10) at RA 00h 25m 18.00s, Dec +64° 08′ 24.0″ within Cassiopeia, alongside peak meridian transit altitudes for 40°N and 30°S observers. Use the RA/Dec Coordinate Converter to compute exact culmination altitude for your latitude.
Astrophysical Context & Structure
Tycho's Supernova Remnant (3C 10, B Cassiopeiae, SNR G120.1+01.4) is the expanding 8-arcminute (~22-light-year) debris cloud of SN 1572, one of the watershed events in the history of science. Appearing suddenly in early November 1572 near Kappa Cassiopeiae and rivaling Venus at visual magnitude −4.0, the 'new star' was measured with unprecedented sextant precision by Danish astronomer Tycho Brahe in his 1573 book De nova et nullius aevi memoria prius visa stella—proving from its complete lack of nightly parallax that the starry heavens beyond the Moon are not immutable.
In 2008, astronomers using the Subaru Telescope captured an optical spectrum of a 'light echo' from SN 1572—original 16th-century flash photons reflected off a distant interstellar dust cloud and arriving at Earth 436 years later. That spectrum proved beyond doubt that Tycho's supernova was a normal Type Ia thermonuclear explosion caused by the runaway carbon-oxygen fusion detonation of a white dwarf near the 1.4-solar-mass Chandrasekhar limit, leaving no central neutron star behind.
Expanding at ~4,000 to 5,000 km/s, Tycho's remnant shines brilliantly in X-rays and radio waves: Chandra X-ray Observatory images show a cauliflower-like interior of silicon, sulfur, and iron ejecta heated by a reverse shock, wrapped inside a razor-thin blue outer ring of non-thermal X-ray synchrotron filaments featuring ordered magnetic 'stripes' where cosmic-ray protons are accelerated to PeV (10^15 eV) energies.
Practical Visual Observing Guide
- Located at RA 00h 25.3m, Dec +64°08′ in north-central Cassiopeia, 1.8° north-northwest of the 4.2-magnitude B-supergiant Kappa Cassiopeiae (κ Cas).
- Because Type Ia remnants lack dense radiative cooling shells, Tycho's SNR emits optically only in ultra-faint, pure Balmer H-alpha filaments (Knot g on the northeastern rim) via charge-exchange shocks, making it strictly an astroimaging and X-ray/radio target rather than a visual eyepiece object.
- Visual observers can star-hop to the exact 8-arcminute field north of Kappa Cassiopeiae and inspect the 12th-to-13th magnitude field stars (including the candidate surviving binary companion star Tycho-G) marking the site where Tycho Brahe saw a −4.0 magnitude beacon in 1572.
Catalog Cross-Identifications & Aliases
Common Aliases: SN 1572 · Tycho's Supernova Remnant · 3C 10 · B Cassiopeiae · SNR G120.1+01.4
| Catalog Authority | Identifier |
|---|---|
| SIMBAD | SN 1572 |
| WIKIDATA | Q23391 |
Related Objects, Comparisons & Guides
Cassiopeia A (3C 461 Young Supernova Remnant)
Coordinates, kinematic distance (3.4 kpc), JWST/Chandra ejecta knots, and high-aperture observing guide for Cassiopeia A (3C 461).
Kepler's Supernova Remnant (SN 1604)
Coordinates, kinematic distance (5.1 kpc / 16,600 ly), SN 1604 history, circumstellar bow-shock knots, and data for Kepler's SNR in Ophiuchus.
SN 1006 Remnant (Brightest Recorded Supernova)
Coordinates, Gaia/kinematic distance (2.18 kpc), −7.5 mag historical peak in 1006 CE, Schweizer-Middleditch background star, and SN 1006 data in Lupus.
Apparent vs Absolute Magnitude Explained
Understand the logarithmic Pogson astronomical magnitude scale, apparent visual magnitude (m), absolute magnitude (M at 10 parsecs), and bolometric corrections.
Measurement Uncertainty & Optics in Astronomy
How random vs systematic errors, asymmetric error bars, model dependencies, and optical aperture/exit-pupil limits shape astronomical measurements.
Scientific Sources & Dataset Provenance
- SIMBAD Astronomical Database (CDS) (2026-10 release): Wenger, M., et al. 2000, A&AS, 143, 9 (The SIMBAD astronomical database) — Centre de Données astronomiques de Strasbourg
- ESA Gaia Archive — Data Release 3 (DR3 (2022-06-13)): Gaia Collaboration, Vallenari, A., et al. 2023, A&A, 674, A1 (Gaia Data Release 3) — European Space Agency / Gaia DPAC
- Revised New General Catalogue and Index Catalogue (RNGC/IC) (2024/2026 edition): Steinicke, W. 2010, Observing and Cataloguing Nebulae and Star Clusters (Cambridge Univ. Press); Verga, M. OpenNGC (CC-BY-SA 4.0 / data tables) — Wolfgang Steinicke / OpenNGC