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in the dark hours before dawn on Monday, April 22. But start watching tonight, anyway. If you trace the paths of these meteors backward on the sky's dome, you'll find that they appear to originate from a point in the sky near the the star Vega, the heavens' 5th brightest star. This is the shower's radiant point. The radiant point for the Lyrid shower sits just to the right of Vega, which is the brightest star in the constellation Lyra the Harp. It's from Vega's constellation Lyra that the Lyrid meteor shower takes its name.
• You don't need to identify Vega in order to watch the Lyrid meteor shower. The idea that you must recognize a meteor shower's radiant point in order to see any meteors is completely false. Any meteors visible the sky often appear unexpectedly, in any and all parts of the sky.
• Why between midnight and dawn? It's because that's when the star Vega - and the shower's radiant point - is above your horizon. Vega rises above your local horizon - in the northeast - around 9 to 10 p.m. local time. It climbs upward through the night. The higher Vega climbs into the sky, the more meteors that you are likely to see. By midnight, Vega is high enough in the sky that meteors radiating from her direction streak across your sky. Just before dawn, Vega and the radiant point shine high overhead. That's one reason the meteors will be numerous then.
• So why near Vega? Why do the meteors radiate from this part of the sky? The radiant point of a meteor shower marks the direction in space - as viewed from Earth - where Earth's orbit intersects the orbit of a comet. In the case of the Lyrids, the comet is Comet Thatcher. This comet is considered the "parent" of the Lyrid meteors. Like all comets, it is a fragile icy body that litters its orbit with debris. When the (Continued on page 28)
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