You can be the greatest observer this planet has ever seen, but if you’re trying to observe galaxies through a 4-inch telescope, your observing log is going to be filled with reports of rough shapes and descriptions like “hinted at” and “small and faint.” There’s no way around it. In my experience, six factors will determine how well your galaxy observing session goes.
This rule seems to provide a good indicator of difficulty. The higher that number (no units, just a number), the tougher the galaxy will be to observe. He multiplied the magnitude by the surface brightness. My late friend, Jeff Medkeff, developed a simple rule to determine how difficult a galaxy will be to see.
Surface brightness is expressed in terms of magnitude per square arcminute, or per square arcsecond for small galaxies. In addition to the brightness of a galaxy (given in terms of magnitude), you must also take into account its surface brightness - the galaxy’s magnitude divided by its area.
0 kommentar(er)
