When you wish upon a Geminid.


Photo from Spaceweather.com by Gregor Srdog-Marino Tumpic,
Sarsoni near Rijeka, Croatia, Dec. 12, 2020Wairarapa


Last Monday night while walking our doggie, I happened to look up into the clear, dark almost-winter sky ... and a giant shooting star streamed past. I yelped! And scared the bejeezus out of my husband, who looked at me with such fear and concern, thinking--he told me later--that we were about to be attacked by a falcon. (I won’t get into the details of ... well, okay, this was sort of a delayed post-traumatic reaction to a story about falconry we’d half-heard on NPR a few mornings before, after which he dreamed falcons were diving at us. I think this fear of urban falcon attacks has mostly passed.)

I felt badly that my razor-sharp reflexes failed me at that moment (it was
cold out there) so instead of yelping something useful like “Omigosh LOOK!” and directing his attention to the stellar streak above us, I uttered some sort of ominous death howl which gave him terrifying flashes of us about to be hopelessly mutilated by bird talons. And because of that he missed the whole thing.

David-Harvey1Photo from Spaceweather.com by David Harvey,
Kitt Peak National Observatory, Tucson, Arizona USA, Dec. 13, 2010

After we both caught our breath, and I reassured him there were no falcons diving at us (I was reasonably sure about that), I told him what I’d seen. That, I announced, was a Geminid! In retrospect I think it was something even cooler--a fireball--and a fine preview of things to come, for the annual Geminid meteor shower was peaking that very evening. We spent the rest of our chilly dog walk peeking cautiously up to the sky so as not to: 1) slip on the treacherously icy sidewalks while attempting to see more meteors; and 2) do anything that might catch the attention of hungry raptors.

I am a skywatcher, such as it can be done on the fringes of a city whose sodium vapor lights mask most of the Milky Way with orange glow. I am moderately conversant in the language of astronomy and space technology. And I love looking up at night and knowing
that’s the Pleiades, that’s Jupiter following the moon across the sky, that’s Venus rising in the east, that’s the International Space Station passing over. (And wait ... is that a really huge bird ...?) I don’t own a telescope (yet), but I do subscribe to Spaceweather.com e-mail updates, so usually I know some of what’s going on up there. And I get very excited about meteor showers. Who doesn’t like to see shooting stars? All those wishes!

Babak-Tafreshi2Photo from Spaceweather.com by Babak Tafreshi,
Zagros Mountains, Iran Dec. 14, 2010

The Geminids--so named because they appear to radiate from the constellation Gemini (specifically the star called Castor)--are famously active, with some estimates for this year’s shower of at least 100 meteors per hour in very dark skies. That meant even we had a good chance of seeing a few, sodium vapor glow notwithstanding.

The catch is that the best time to catch them is in the dead of night when it’s five frigid degrees and you should be tucked between your warm flannel sheets dreaming of sugarplums. Usually I sleep through meteor showers, but it so happened I woke up around 2:00 a.m. the next morning. Prime meteor viewing time! After a 30-minute internal debate between staying in my nice warm bed vs. seeing the
most spectacular meteor shower of the year that I was actually awake for (said debate making me ever more awake and alert, so falling back to sleep was out of the question), I finally bundled up and slipped out of the house.

Outside in the very cold, very quiet night (except for my boots scrunching
loudly on the crusty snow), I leaned against a tree and looked up. The sky was deep dark velvety blue, scattered with a few bright crisp constellations, most notably Orion -- a constellation so impressively huge and recognizable I can’t help but stare at it. Ah, but the trick to catching meteors is to look between the stars, at the blank dark spaces -- not easy because our eyes are drawn to all the twinkly things.

After a few minutes, I adjusted and focused on the darkness, sometimes scanning the sky, sometimes fixating on one spot. Then finally,
flit! A sliver of white sliced the sky for a second, then vanished, like the final moments of a fireworks sparkle dropping from the sky and quickly fading. Thrill! I massaged my neck for a moment, then looked up again to watch for more. I should have been in a reclining lawn chair (which we don’t have) or lying on the ground (on about 20 heated mattresses), but there was only a tree to lean against so I had to occasionally relieve my achey neck from all the upward craning.

P-M-HedAcn1
Photo from Spaceweather.com by P-M Hedén,
Vallentuna, Sweden, Dec. 15, 2010

The Geminids are unique among meteor showers in that the source is not the usual debris-spewing ice ball commonly known as a comet. When comets swing past Earth their debris collides with our atmosphere, burning up in white streaks we call shooting stars. The Geminids emanate from an asteroid -- or, to use Nasa’s scientific term, a “weird rocky object” called 3200 Phaethon. Although occasionally suspected of accidentally killing off dinosaurs, asteroids don’t usually carry lots of debris with them, as comets do. Scientists are still trying to figure out how 3200 Phaethon creates enough celestial rubble to cause one of the busiest meteor showers each year. Nevertheless, it orbits merrily around our solar system, flinging loads of meteors through our atmosphere every December, resulting in a profusion of wishable shooting stars.

Back on Earth, I managed to catch six meteors in the space of half an hour -- some like a flicker in my peripheral vision (
was that a meteor? or just a star appearing from behind a tree branch?) and some a split-second streak (like the one in the animated photo above) that fell exactly where I happened to be looking. All of them were magical, even if they came and went in the blink of an eye. I could have watched all night but it was cold, I was tired, and they weren’t exactly flying out of Gemini at an eye-popping rate -- at least not over our house. Once inside I kept peeking out the windows hoping to see just one more. I saw three! then put myself to bed -- happy that I hadn’t missed it after all, and comforted knowing there was something special happening above us.

I’ve been tracking meteor showers through Spaceweather.com for several years now, and have been outside in the wee hours to catch only a few of them. I don’t know if it was coincidence ... or something more cosmic? ... that made me look up precisely when that fireball zipped overhead. If it hadn’t, I might not have been so willing to stand in my frozen back yard scanning the sky for flaming bits of space rock. The moon, stars and planets doing nothing at all in the sky is magic enough -- but when light shoots around quietly (or actually not so quietly -- click to hear what a meteor sounds like) in the night, I want to see it!

We may see only a fraction of the Milky Way’s full splendor in our suburban Chicago skyscape, but a good number of planets, moons, stars, comets, meteorites, asteroids and other twirling, whizzing, icy, molten, cosmic leftovers from the Big Bang manage to shine through the veil of city lights, bringing the huge and distant awesomeness of the Universe to our little planet. If we miss the rare passage of an unusually bright comet, we can look forward to a more common lunar eclipse--mark your calendars for the next one December 21, 2010.

Babak-Tafreshi4Photo from Spaceweather.com by Babak Tafreshi,
Zagros Mountains, Iran Dec. 14, 2010

There’s always something (but hopefully not man-eating falcons) to see in our skies at night -- just step outside and look up! And by the way, I made just one wish after seeing all those shooting stars, and it was for more northern lights.

As always, feel free to leave a comment.