M1: Crab Nebula
Season Visible in Evening
Supernova recorded by Chinese, July 4, 1054.
This object is not particularly interesting visually, being small and faint. And it’s hard to find. I keep it in my inventory of things that I can find because it’s moderately well-known; the kind of thing that a visitor to the scope who has done some reading on Astronomy would ask to see.
It also makes a good target for a beginner ready to start seeking more challenging objects, as it is somewhat faint, and is situated so that a little more skill with positioning the scope and using the finder are necessary. It also makes a good target for beginners venturing into astrophotography, as a photograph will show far more detail than can be detected with your eye at an eyepiece.
M1 is a supernova remnant: a snapshot of the aftermath of a stellar explosion that occurred almost a thousand years ago. Ancient Chinese astronomical records record that on July 4, 1054, a “new star” appeared in the sky and shone brilliantly for several days, then faded away. That was a supernova – a formerly dim or invisible star exploding violently. M1, viewed now, is the still-expanding cloud of gas and debris from that explosion.
M1 is located in Taurus, above Orion. I find it easiest to locate Orion first, by looking in the southern Winter sky for his distinctive 3-star “belt”, then filling in the rest of the stars.
Learn to quickly find Orion, Taurus, Auriga, and Gemini. They are useful for finding dozens of objects in the Winter sky.
In light-polluted city skies you won’t be able to see all the stars in these constellations, but you will be able to see their brightest stars, and this is enough to mentally trace out their shapes.
The objective of all of this study of the region is to find Zeta Tauri, the star at the end of the lower of the two horns of Taurus, the bull.
It is a dim star, above Orion, roughly on the line between Betelgeuse and Capella, about a third of the way along from Betelgeuse. Once you have found this star, it is easy to see that it is the extension of the horns defined by the brighter “V” shaped cluster of stars that include Aldebaran.
Here is the same star field. Practice finding Zeta Tauri.
The point of all this is that M1 is just above and to the right of Zeta Tauri. If you place the middle circle of a Telrad finder on Zeta Tauri, at about “7:00” on the circle, you are pointed at M1.
Let’s look at the area around Zeta Tauri, above Orion, more closely.
A Telrad finder is perfect for this because of its calibrated circles. If you have a Telrad, place Zeta Tauri on the middle circle, at about the “7:00” position.
If you have a more traditional magnifying finder scope, position Zeta Tauri below and to the left of centre. (This assumes a “correct-image” finder. If you have the kind of finder that inverts or reverses the image, you will have to go above and to the right of centre instead. I highly recommend you change to a “correct-image” finder.)
If you have only a simple “red dot” finder, position the dot slightly above and to the left of Zeta Tauri. The distance from Zeta Tauri is about the same as the separation between two stars in Orion’s belt.
M1 should be visible as a very dim patch of light. This image simulates what you might see in a 100 mm telescope using the typical 25mm Plossl eyepiece that comes with such scopes.
This image simulates the view in a 200 mm scope, such as the very popular 200 mm Schmidt-Cassegrains, with the included 25mm Plossl eyepiece.
Aren’t nebulae supposed to be swirls of amazing colours? Not when viewed with your eyes – here is an explanation.
All the above images were generated with Starry Night Pro.