SN 1895B was a supernova event in the irregular dwarf galaxy

NGC 5253 NGC 5253 is an irregular galaxy in the constellation Centaurus. It was discovered by William Herschel on 15 March 1787. Properties NGC 5253 is located within the M83 Subgroup of the Centaurus A/M83 Group, a relatively nearby galaxy group that i ...

, positioned east and north of the galactic center. It is among the closest known extragalactic supernova events. The supernova was discovered by

Williamina Fleming (15 May 1857 – 21 May 1911) was a Scottish-American astronomer. She was a single mother, hired by the director of the Harvard College Observatory to help in the photographic classification of stellar spectra. She helped develop a common d ...

on December 12, 1895 after noticing an unusual spectrum on a

photographic plate Photographic plates preceded photographic film as a capture medium in photography, and were still used in some communities up until the late 20th century. The light-sensitive emulsion of silver salts was coated on a glass plate, typically thinn ...

taken July 18, 1895, and was initially given the

variable star designation In astronomy, a variable star designation is a unique identifier given to variable stars. It uses a variation on the Bayer designation format, with an identifying label (as described below) preceding the Latin genitive of the name of the constell ...

Z Centauri. The

light curve In astronomy, a light curve is a graph of light intensity of a celestial object or region as a function of time, typically with the magnitude of light received on the y axis and with time on the x axis. The light is usually in a particular frequ ...

is consistent with an event that began ~15 days before the discovery plate was taken, and this indicates the supernova reached a peak visual magnitude of up to 8.49. ZCenLightCurve

After the light faded, the

remnant Remnant or remnants may refer to: Religion * Remnant (Bible), a recurring theme in the Bible * Remnant (Seventh-day Adventist belief), the remnant theme in the Seventh-day Adventist Church * ''The Remnant'' (newspaper), a traditional Catholic ne ...

has remained undetected at any wavelength, including

X-ray An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30&nb ...

and

radio Radio is the technology of signaling and communicating using radio waves. Radio waves are electromagnetic waves of frequency between 30 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmit ...

. This suggests the expanding remnant is meeting a low density of surrounding interstellar material, which would be consistent with certain double

white dwarf A white dwarf is a stellar core remnant composed mostly of electron-degenerate matter. A white dwarf is very dense: its mass is comparable to the Sun's, while its volume is comparable to the Earth's. A white dwarf's faint luminosity comes fro ...

merger scenarios. The remnant is expected to reach peak radio emission around the year 2195, and it may become detectable at that time.

References

External links

Light curve
on th
Open Supernova Catalog
{{DEFAULTSORT:SN 1895B Supernovae

Centaurus Centaurus is a bright constellation in the southern sky. One of the largest constellations, Centaurus was included among the 48 constellations listed by the 2nd-century astronomer Ptolemy, and it remains one of the 88 modern constellations. ...

Durchmusterung objects 118843 Centauri, Z 18950707