A wonderful image of the remnant of the first known supernova. The Chinese 1800 years ago called it a guest star
First supernovathat has been documented by mankind is SN 185. In 185 AD, astronomers and chroniclers in ancient China saw a powerful flare in the sky that lasted for the next 8 months. Old Chinese researchers classified it as the so-called “guest star” (kèxīng) – a luminous object that appeared in an unchanging position relative to other celestial bodies, to disappear completely after some time. We already know that the “guest stars” were exploding novae and supernovae; now we have the opportunity to look at the remnants of SN 185 known as RCW 86 in all their glory.
A wonderful, wide-field image of the object in question was taken by the Dark Energy Camera for dark matter and energy research, mounted on the 4-meter Victor M. Blanco Telescope in Chile. Its enormous resolution (570 megapixels) allowed it to capture cosmic “clouds” that seem to move away from a central point. It is worth noting that the SN 185 itself exploded over 8,000 times. light years from Earth – ancient Chinese astronomers spotted it between the constellations of Circus and Centaurus, looking more or less in the same direction as the nearest star system, Alpha Centauri.
RCW 86 – Supernova Remnants SN 185 (photograph)
The important thing is that until relatively recently it was thought that RCW 86 could not be a remnant of SN 185 – initial calculations suggested that for the matter to disperse as far from the dead star as in this case, it would need at least 10,000 km. years. However, observations by the Spitzer telescope in 2006 allowed to identify in the aforementioned “clouds” significant amounts of iron, characteristic of the most energetic Type Ia supernova explosions. This type of explosion occurs in binary systems when a dense white dwarf sucks material from its companion star until it explodes. Its power is so great that it speeds up the dispersal of the supernova remnant.