I continue to process piled data… Let warmup for the new M1 season with a processing an image taken in the end of the previous two Included are sub taken in Feb 2022/2023. These from 2022 were just a test, but are thrown into the mix

My tradition is to pack all non-testing images with some information, no matter how famous the object is. Someone can find something new or just like reading it

M1, NGC 1952 or the Crab nebula is located in the constellation Taurus. It is first identified in 1731 by John Bevis, but because the internet was very slow by these years , it was independently re-discovered in 1758 by Charles Messier (and most likely by others during these almost 30 years). Charles Messier has been trying to find Haley’s comet - predicted to return in late 1758. Because M1 is near the ecliptic where the comet hunt happens, he mistaken that fussy blotch with the Haley’s comet. Messier decided that it would be handy to have a list of the “static” objects with their coordinates, in order to easily identify if something is a comet or not. Till the end of his life, that catalog grew to 103 objects. Yes, we all know that Messier’s Catalog contains 110 objects, but this is after the last update made in 20th century.

The traces of M1 are traced back to the year 1054. In the archives of at least five Chinese astronomers there are records for a “guest star”, so bright that was possible to be seen during the day and to read on its light during the night. The earliest reported date is July 4th… We don’t know how many clouded days/nights there were between explosion and the discovery, but by that time there were no much telescope purchases, so maybe they had more clear skies These are the first identified records for observing supernova explosion.

M1 is around 6500 l.y. away from Earth and has a diameter of around 10 l.y. The measured expansion speed is ~1500 km/s or 0.5% of the light speed. The explosion left one of the first discovered pulsars. This neutron star is 28-30 km in diameter and spins 30.2 times per second. Knowing the exact date (a few difference days is not counted) is priceless for the scientists and helps them to explore the pulsars' nature.

It is not known how bright the star was before the explosion. However, it should be less than the naked eye limit. Maybe it would be in the range of the current amateur binoculars and telescope as M1 is located in the near-by Perseus Arm of Milky Way… The nebula from this image had been just a smaller or bigger dot 970 years ago!

https://www.astrophotography.app/