The great nebula in the constellation of Orion the Hunter. On a good clear night, from a dark site well away from the lights of modern civilization, this glowing cloud of gas and dust can be seen with the naked eye as a fuzzy patch surrounding the star Theta Orionis in the Hunter's Sword, below Orion's belt. It is probably the most spectacular of all the objects cataloged by Charles Messier and now called by their `M' numbers. M42 had been known since the beginnings of recorded astronomy as a star, but it is so outstanding that it was first noted as an extended nebula in 1610, only a year after Galileo's first use of the telescope. Detailed descriptions started appearing later in the seventeenth century, and it has been a popular target for anyone with a telescope ever since. So many details are visible in even a small telescope that M42 will more than repay the observer who makes it a frequent target, and who will find that it is hard to make a realistic sketch that can capture all of the finer features. Observation date: October 1, 1973. Original Ektachrome color transparency.