One of the best ways is to take note of the stars each night as they creep out one by one after sunset. If you take your place at the window to-morrow night as the twilight fades away, you will see them gradually appear, now in one part, now in another of the sky, as
"One by one each little star
Sits on its golden throne."
The first to appear will be Sirius or the dog-star (see Fig. 54), that pure white star which you can observe now rather low down to the south, and which belongs to the constellation Canis Major. As Sirius is one of the most brilliant stars in the sky, he can be seen very soon after the sun is gone at this time of year. If, however, you had any doubt as to what star he was, you would not doubt long, for in a little while two beautiful stars start into view above him more to the west, and between them three smaller ones in a close row, forming the cross in the constellation of Orion, which is always very easy to recognise. Now the three stars of Orion's belt which make the short piece of the cross always point to Sirius, while Betelgeux in his right shoulder, and Rigel in his left foot (see Figs. 54 and 55), complete the long piece, and these all show very early in the twilight. You would have to wait longer for the other two leading stars, Bellatrix in the right shoulder and κ Orionis in the right leg, for these stars are feebler and only seen when the light has faded quite away.
Fig. 54.
Some of the constellations seen when looking south in March from six to nine o'clock.
By that time you would see that there are an immense number of stars in Orion visible even to the naked eye, besides the veil of misty, tiny stars called the "Milky Way" which passes over his arm and club. Yet the figure of the huntsman is very difficult to trace, and the seven bright stars, the five of the cross and those in the left arm and knee, are all you need remember.
No! not altogether all, for on a bright clear night like this you can detect a faint greenish blue patch (N, Fig. 54) just below the belt, and having a bright star in the centre. This is called the "Great Nebula" or mist of Orion (see Frontispiece). With your telescopes it looks very small indeed, for only the central and brightest part is seen. Really, however, it is so widespread that our whole solar system is as nothing compared to it. But even your telescopes will show, somewhere near the centre, what appears to be a bright and very beautiful star (see Fig. 55) surrounded by a darker space than the rest of the nebula, while in my telescope you will see many stars scattered over the mist.