26 Jun 2024
I always wondered why M1 was nicknamed "Crab Nebula", as it does not look at all like that animal. It seems to come from the interpretation by John Pringle Nichol of a drawing by Lord Rosse made in 1842-43 (see second picture). More details are available in Ian Ridpath's excellent article http://www.ianridpath.com/startales/rosse-crab.html
M1
4 credit
Filtro | Exp. media (s) | Esposizione totale | Sottoframe |
|---|---|---|---|
| Luminance | 57 | 22m | 23 |
| Green | 42 | 16m | 23 |
| Red | 44 | 16m | 22 |
| Blue | 44 | 16m | 22 |
| Halpha | 573 | 3h30m | 22 |