We’re in for some sky excitement the next couple nights. Tonight there’s a fair chance for northern lights as blustery solar winds
arrive from another coronal hole at the Sun.
Forecasters are calling for a G1 or minor geomagnetic storm that’s expected to kick in this
afternoon and last into the early morning hours Wednesday. With the moon only a crescent, we’ll have dark skies for aurora watching. Look for that telltale twilight-like glow in the northern sky at nightfall as a tip-off that a display is in progress.
Then, starting Wednesday and continuing through Thursday morning the annual Lyrid meteor will salt and pepper the sky with meteors. We’ve waited more than three months since the January Quadrantids for a meteor shower to return, so I’m looking forward to this one.
Like the first flowers, the Lyrids return every April with a peak rate of 10-25 meteors per hour. They originate or radiate from a point in the sky about an outstretched fist southwest of bright Vega in the constellation Lyra the Harp.
Even though the radiant actually lies in neighboring Hercules, the shower’s always been associated with Lyra (Lyrids) both because of Vega’s dominance and the original, loosey goosey borders of the constellations. Before 1930, the borders of the 88 constellations were vague and the Lyrids were close enough to Lyra to assume its name. Had the shower turned up after the International Astronomical Union precisely defined borders, we’d be calling them the Herculids!
Although not a big-time shower like the August Perseids, this should be a good year for the Lyrids. You can start watching around 11 o’clock local time Wednesday night (April 22) when Vega climbs above the treeline in the northeastern sky. Rates will increase through the night and peak around 4 a.m.-5 a.m. when the radiant is highest in the sky just before dawn.
Dress warmly, pack a hot beverage and get comfy in a reclining chair. Or a hot tub. In which case, don’t dress warmly. Those are my mantras for any meteor shower. Even though Lyrids will radiate from a particular direction, they can show up anywhere in the sky. Early in the evening, you’re best to face east. Prefer the early morning? Face southeast.
Like many meteor showers, the Lyrids are the flotsam and jetsam of comets. You’ve been reading about all the dust released by Rosetta’s comet as it’s warmed by the Sun. Comets that cross Earth’s path put that dust to good use. As we speed into the debris sputtered from their nuclei, the particles strike our atmosphere and incinerate in a blaze of light to make a meteor.
C/1861 G1 (Thatcher), which takes roughly 415 years to make one orbit around the Sun, is responsible for the Lyrids. Every so often we pass through a thick filament of dust deposited by Thatcher and get treated to an outburst of Lyrids with numbers reaching more than 100 per hour. That’s expected to happen in 2040 and 2041, so stick around.