Tonight – April 20, 2017 – the Lyrid meteor shower is picking up steam. We expect some Lyrid meteors to fly between late evening on Thursday, April 20 until dawn Friday, April 21. And we anticipate Friday night until dawn Saturday being even better. On both nights, try watching in the few hours before dawn. That’s when the radiant point – near the star Vega in the constellation Lyra – is highest in the sky. For that reason, it’s when you’re likely to see the most meteors.
Note for Southern Hemisphere observers: Because this shower’s radiant point is so far north on the sky’s dome, you’ll see fewer Lyrid meteors. But you might see some! Try watching between midnight and dawn on April 22.
On a dark night, this shower typically offers about 10 to 15 meteors per hour at its peak. Fortunately, in 2017, the waning crescent moon should enhance the show, more than it intrudes on it.
The shower’s radiant point is just to the right of beautiful blue-white Vega, which is the brightest light in the constellation Lyra the Harp. Vega will be bright enough to overcome the glare of some light-polluted cities. What’s a radiant point? If you trace the paths of these Lyrid meteors backward on the sky’s dome, you’ll find that they appear to originate from near Vega, which is the heavens’ 5th brightest star.
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 meteors radiant from a point near this star, but they’ll appear unexpectedly, in any and all parts of the sky.
However, knowing the rising time of the radiant point helps you know when the shower is best in your sky. Assuming you’re in the Northern Hemisphere, 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 you’re 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, and the meteors will be raining down from the top of the sky (assuming you’re in the Northern Hemisphere).
Why do the meteors radiate from a single 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’s a fragile icy body that litters its orbit with debris. When the bits of debris enter Earth’s atmosphere, they spread out a bit before they grow hot enough (due to friction with the air) to be seen. So meteors in annual showers are typically seen over a wide area centered on the radiant, but not precisely at the radiant.
Only 10 to 15 meteors per hour doesn’t sound like many. But even an hour under a still, dark sky – raining down a dozen or so meteors – is a treat. Plus, the April Lyrids can surprise you. They’re known to have outburts of several times the usual number – perhaps up to 60 an hour or so – on rare occasions. Meteor outburts aren’t always predictable. So – like a fisherman – you’ll want your lawn chair, a thermos of something to drink, whatever other gear you feel you need – and then you need to wait. Not a bad gig.
Bottom line: On any clear night around April 20-23, 2017, the Lyrid meteor shower will kick off at late evening. In 2017, the peak numbers of Lyrid meteors are expected to light up the wee hours before dawn on April 22.