See the Lyrid Meteor Shower the Night of April 21–22

A good car is a dependable vehicle you can always count on. The Lyrids are like that. Every year, rain or starshine, they're active from April 14–30, with the peak occurring midway through the run. This year, that happens on Monday night-Tuesday morning, April 21–22, when observers under minimally light-polluted skies might see 15 to 20 meteors per hour from roughly midnight until the start of dawn.

Each meteor is a small shard of Comet Thatcher (C/1861 G1). They are heated by air compression as they enter Earth's atmosphere in excess of 175,000 kilometers per hour (110,000 mph). Every April, Earth cuts across the comet's orbital path, where the debris is concentrated, and a meteor shower results. Larger fragments produce the occasional Lyrid fireball.

The Lyrids' origin point, called the radiant, is located about 8.5° west-southwest of Vega in Hercules. They should properly be called the April Herculids, but before the International Astronomical Union (IAU) set constellation boundaries in 1930, no one was quite sure where Lyra ended and Hercules began, the reason for the disparity.

A meteor shower's radiant is really a vanishing point, a point in space where parallel lines appear to converge and meet in the distance. Parallel railroad tracks do the same for the same reason. Proportionally, the tracks take up less and less of our field of view the farther we follow them into the distance until they ultimately shrink down to a point. Likewise, sand-size grains shed by Comet Thatcher arrive on parallel paths from a great distance. Drawn backwards, their paths converge at a point in space — the radiant.

The Lyrids' radiant stands almost 20° high by 10:30 p.m. local time. Although the horizon will cut off a fair number of meteors that flash below the radiant, they have free reign above this point, so we'll start to see activity. Dress warmly and get comfortable in a lounge chair while facing southeast or north. Personal experience has shown that the Lyrids require perseverance. There may be gaps of 5 minutes or more between meteor sightings.

Meteors streaming directly at the observer from the radiant will look like points or "dashes" of light, while those on paths that peel off in other directions from the radiant will leave longer trails. To see a grab bag of both, place Vega in your peripheral vision so your eyes are directed some distance away from the radiant.

Post-midnight viewing is generally the best, especially from 2 a.m. to 5 a.m. when Lyra stands high above the horizon. The Moon joins the scene around 4 a.m. local time but interferes only a little. The 36% thick crescent rises in Capricornus about an hour before the start of dawn. You might be tempted to return to bed once the sky brightens. But if you do, you'll miss seeing Saturn's return. Look for it about 5° south of the crescent Venus low in the southeastern sky. Twilight may make it necessary to use binoculars to spot the ringed planet, but you'll really want to see it up close in a telescope.

Earth crossed Saturn's ring plane on March 23rd, when for a brief time the rings would have disappeared in amateur telescopes. Unfortunately, solar glare dashed our chances of seeing this unique presentation. Nonetheless, a potentially amazing sight awaits. We now see the south side of the ring plane — last visible in 2009 — tilted a slivery-thin 1.7° to our line of sight in late April. Will you see them (check photo above), or will the planet appear ringless in a bright sky?

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If you read my recent post about U Geminorum being on the cusp of an outburst, it happened! The star began to brighten on April 8th and has been at maximum light the past few nights. Thanks to a tip from reader John Dolby of Tucson, I spotted it at magnitude 9.6 on April 15th. Catch it if you can.